archived-arbor-press-dev

Hey everbody, welcome to the channel about my graduation project! As you can read in the channel name, I'll be working on redesiging the classic PP injection machine into an improved arbor-press design. I'll regularly post updates here on how stuff is going. Any of your help and feedback is greatly appreciated! To give you an idea, my project will focus on the following:

On the user side of this assignment, I'll research the context of low-and-middle-income countries and deliver a design optimized for these building settings.
On the technical side, I'll deliver a validated, functioning prototype of the injection machine.
The open source side focuses on researching the best practices within Open Source ecosystems and delivering a building manual for the injection machine that stimulates feedback to Precious Plastic from builders on their proposed improvements.

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4:22 PM

Some links to give you an idea about existing arbor-style presses: https://www.youtube.com/watch?v=I9ELddW7wjE https://www.instagram.com/p/CWtHa4ONAC3/

Thanks for the intro @Joostie !! Really looking forward to see this come together. A well documented Arbor Press is going to take well in the PP community I believe

I am very interested in how you will approach the way the mould attaches to the barrel.

@Landry did you ever end up building the arbor press that Vincent designed?

Yes i build it

12:34 PM

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1

Nice!! how did it work?

What do you think about making this channel public??

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1

Hey! If you ever build an injection machine, you could help me improve the design by filling this survey: https://forms.gle/ZGyYhUCDFsoP4Tgu8 Thanks a lot!

Joostie

Hey! If you ever build an injection machine, you could help me improve the design by filling this survey: https://forms.gle/ZGyYhUCDFsoP4Tgu8 Thanks a lot!

https://osr-plastic.org/machines/elena.html#overview

Arbor Injection Elena Standard

Overview Build Resources Media This is the most stable, robust, complete, powerful and precise injector in it's class and has been copied many times. ...

6:59 PM

isnt that just the elena in the pic?

Great project. I need to build this style of injection machine because of space constraint in my shared-garage-workshop. I am in doubt if to fill the survey because the machine is not built, but i am researching a lot for solutions. I don't know if it is useful for you to share these raw info, maybe it is best to share something more defined. It will take a month minimum for me, though

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2:16 PM

https://leantechnik.com/us/leansl/ this is an interesting component for the rack and pinion, but i have yet to find an answer about pricing

sven.schuermann

leanSL - leantechnik AG

2:19 PM

https://leantechnik.com/en/enterprise/who-we-are/

hauptuser_site

Who we are - leantechnik AG

2:24 PM

https://www.ebay.it/itm/254818652902?hash=item3b546012e6:g:XHsAAOSwHmJfAEWb

Farymann Cremagliera Pignone Diesel Motore Baumaschinen Bootsmotore...

Le migliori offerte per Farymann Cremagliera Pignone Diesel Motore Baumaschinen Bootsmotoren sono su eBay ✓ Confronta prezzi e caratteristiche di prodotti nuovi e usati ✓ Molti articoli con consegna gratis!

2:26 PM

car rack for 9 euros on ebay. if you can incorporate them in the design (dimensions, angles etc) There is great economy on ebay for used car's rack and pinion drive systems

@sponsoons isn't Elena just Talleres Esférica's?

OS is about sharing for the greater good benefitting society at large. No one does it so we have to do it

Harbor press has been pioneered by talleres esférica, copied by plastichub and eventually replicated independetly by many more in the community. It's a machine many people need around the world, so we'll research on previous iteration, try to improve existing issues and share with the world how to replicate it. More people replicating, more people recycling, less plastic out there. Easy.

1

Mattia

@sponsoons isn't Elena just Talleres Esférica's?

OS is about sharing for the greater good benefitting society at large. No one does it so we have to do it

Harbor press has been pioneered by talleres esférica, copied by plastichub and eventually replicated independetly by many more in the community. It's a machine many people need around the world, so we'll research on previous iteration, try to improve existing issues and share with the world how to replicate it. More people replicating, more people recycling, less plastic out there. Easy.

idk man,thats just the name i know it by

@sponsoons eheh bit of background story.. we prefer to call it by its technical name

ah ok

2:04 PM

i just didnt want anybody to work from the groud up cuz they didnt know something existed

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2:05 PM

ive done that too many times ):

thanks @sponsoons, yes that's a valid point. We were aware of the Elena model

This actually brings me to a question I wanted to ask @Joostie: Are you planning to gather all the (arbor) injection machine designs that are out there in the community already, and make a sort of "pro and con" analysis to then be able to pick out the good elements? That would be super interesting!

5:40 PM

Also just thank you for working on this, I'm very excited

@Joostie I filled out your form. Send me a DM if you have any questions or want to know any more

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I have just filled out your form before seeing this channel. Happy to help

3

Hi I have a design for an arbor press which I can share if anyone's interested, it's similar to Plastic Hub's Elena.

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8:48 PM

My version aims to simplify the construction and adds a moving nozzle with spring return to use the injection force as also mould clamping

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1

Another good one out there I haven't seen mentioned is the PP Melbourne. Made of wood which is super cool. So could maybe be made with cheaper tools. https://www.instagram.com/p/CY7rkBWrD4u/?utm_medium=copy_link

preciousplasticmelbourne

The ⭐️ Pro-Series ⭐️ Injection Machine!

This epic piece of equipment has a quick production output and high precision - you’ll be amazed at what you can create! Features:

Height adjustable spring-loaded barrel

Rack and pinion system, allowing for higher pressure

Gears convert rotation into linear motion

The ability to bolt to the gro...

Likes

112

5

2

https://www.youtube.com/watch?v=vW0-uMh0KAw&t=313s

One Army

Monthly News #17 - Clean sunglasses from recycled plastic

11:10 PM

A view of esferica's arbor press

11:10 PM

https://loadlimit.com/Hebezeuge/Winden/Schleusenwinde-SCH-W-15-Sifeku.p-604.html

Schleusenwinde SCH-W | 15, Sifeku

Schleusenwinde SCH-W | 15, Sifeku: Die zuverlässige Schleusenwinde zum Öffnen und Schließen von Schütztafeln in Schleusenwerken. • Die ...

11:12 PM

one choice for the rack and pinion system- 495 euro is pricey tough. I am just trying to ballpark componens' prices to make better design choices

https://www.amazon.it/IDRAULICA-MANUALE-OFFICINA-TONELLATE-PIEGATRICE/dp/B012A9N5W8/ref=sr_1_7?__mk_it_IT=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=34QGA2PXX2DB8&keywords=pressa&qid=1649194826&sprefix=pressa%2Caps%2C223&sr=8-7

PRESSA IDRAULICA MANUALE DA GARAGE OFFICINA 12 TONELLATE PIEGATRICE...

PRESSA IDRAULICA MANUALE DA GARAGE OFFICINA 12 TONELLATE PIEGATRICE OFFICINA

11:44 PM

140 euros for that product , it is an interesting frame because you can unmount it and so it is portable

11:45 PM

sorry guys i wouldn't spam the thread, tell me if i am going offtopic. i am just getting used to discord chat style

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@blastic

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Rory - Sustainable Design Studio

@Joostie I filled out your form. Send me a DM if you have any questions or want to know any more

Awesome man thanks!

Kat

thanks @sponsoons, yes that's a valid point. We were aware of the Elena model

This actually brings me to a question I wanted to ask @Joostie: Are you planning to gather all the (arbor) injection machine designs that are out there in the community already, and make a sort of "pro and con" analysis to then be able to pick out the good elements? That would be super interesting!

Yes that's exactly the plan! I'm trying to find the best practices among Arbor machine builders and intergrate them into a PP-proof design

Timberstar

Click to see attachment 🖼️

Cool stuff! Can you tell me more about the mold clamping bit you have going on below @Timberstar ?

10:32 AM

@all thanks a lot for your ideas & existing designs, do keep 'm coming! Also if you could send the survey-link to everyone you know with arbor or lever injection press, that would be great

https://forms.gle/ZGyYhUCDFsoP4Tgu8

Injection Machine Survey

1

@Joostie potentially a kickoff meeting with people interested could be a great way to gather a bit of momentum and create a collaborative environment to develop this machine with the community in the open. Could even be done here on Discord (same features as zoom.. or at least enough for what we would need). Hope not to mess up you plans

if so forget about this.. VERY EXCITED

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Mattia

@Joostie potentially a kickoff meeting with people interested could be a great way to gather a bit of momentum and create a collaborative environment to develop this machine with the community in the open. Could even be done here on Discord (same features as zoom.. or at least enough for what we would need). Hope not to mess up you plans

if so forget about this.. VERY EXCITED

Yes we should definitely do that! At this moment I'm doing context research to prepare for the development phase, so when I'm actually starting designing the thing I definitely want to meet you all

Thanks, good suggestion, I'll keep you posted

(edited)

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That flywheel concept to gain pressure is a remarkable thing. That is a screenshot from the community page of the machine section of PP's website

3:37 PM

I just don't understand how it works though

blastic

That flywheel concept to gain pressure is a remarkable thing. That is a screenshot from the community page of the machine section of PP's website

yes that's the "original" arbor press if you wish.. Taller Esferica originally developed it because they needed much much more pressure to achieve their stunning sunglasses. From then many peeps made iterative improvements to their designs and I believe we now have already a pretty decent arbor press out there.. just need to open source it now to unleash thousands builds

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2

aha!! that in the photo is now kinda a prototype, that maybe evolved into the rack and pinion system. Thanks Mattia

3:44 PM

Taller Esferica work is so inspiring. I find their mould concept is so good, too. And nozzle style and the type of product they made... And also the idea to follow a decentralized production system for their great product is very pioneering and corageous. That gives really the feeling of a working style that can grow, or evolve

3

Yes, truly inspirational.. they've been pushing small scale recycling since the very beginning. We should invite them here!

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Joostie

Cool stuff! Can you tell me more about the mold clamping bit you have going on below @Timberstar ?

On my version there is a base plate with adjustable height, which the mould sits on, and then the barrel and nozzle moves up and down on a spring return, so when you start to turn the handwheel it will push the whole barrel down until it meets the mould inlet, then it will start to push plastic into the mould. This arrangement means that the injection force is the same force which holds the mould closed, in theory that means the clamping pressure and injection pressure will be automatically in balance. When the wheel is turned back the other way the spring lifts the barrel up and the mould is released. That's the method used on some commercial machines eg Robotdigg's pneumatic injectors

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4:43 PM

I haven't built the machine so I have no idea if it works in practice!

Mattia

Yes, truly inspirational.. they've been pushing small scale recycling since the very beginning. We should invite them here!

yes please

Joostie

Yes we should definitely do that! At this moment I'm doing context research to prepare for the development phase, so when I'm actually starting designing the thing I definitely want to meet you all

Thanks, good suggestion, I'll keep you posted

(edited)

The other part I concentrated on was the pinion gearbox, I coupled the handwheel hub to the outside of the pinion gear rather than transferring the torque through the axle which is prone to snapping, and there is no ballbearing in there, it bears directly against the aluminium body of the gearbox. All for simplicity, strength and ease of manufacture. STL file available for anyone who's interested, PM me (edited)

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Timberstar

On my version there is a base plate with adjustable height, which the mould sits on, and then the barrel and nozzle moves up and down on a spring return, so when you start to turn the handwheel it will push the whole barrel down until it meets the mould inlet, then it will start to push plastic into the mould. This arrangement means that the injection force is the same force which holds the mould closed, in theory that means the clamping pressure and injection pressure will be automatically in balance. When the wheel is turned back the other way the spring lifts the barrel up and the mould is released. That's the method used on some commercial machines eg Robotdigg's pneumatic injectors

do you think this spring pressure action could be used to also open a gate aperture on pressure, and close on release on the nozzle end? some sort of spring loaded follower mechanism...

CitSciWorkshop

do you think this spring pressure action could be used to also open a gate aperture on pressure, and close on release on the nozzle end? some sort of spring loaded follower mechanism...

in my experience,valves with plastic are tricky at best

4:53 PM

normally theyll just get stuck in place

I've heard similar things about ball valves.

CitSciWorkshop

do you think this spring pressure action could be used to also open a gate aperture on pressure, and close on release on the nozzle end? some sort of spring loaded follower mechanism...

I didn't get as far as designing a nozzle gate, when I designed this I was collaborating with Plastic Hub and he has his own design for that, I have not ventured into that side of things. I think to operate the gate it would need a seperate spring mechanism.

sponsoons

normally theyll just get stuck in place

yeah I think probably something more basic would work better, just a sliding gate maybe

Timberstar

I didn't get as far as designing a nozzle gate, when I designed this I was collaborating with Plastic Hub and he has his own design for that, I have not ventured into that side of things. I think to operate the gate it would need a seperate spring mechanism.

if anybody feels like messing around with it,he's got the open source files for it on his website (edited)

Timberstar

yeah I think probably something more basic would work better, just a sliding gate maybe

the sliding gates ive tried didnt work,but that could be cuz they were designed without much effort

sponsoons

if anybody feels like messing around with it,he's got the open source files for it on his website (edited)

Did anyone hear from him recently? He deleted his discord server and has gone silent as far as i know

Still trying to work how I can apply it so it is incorporated into the main action of pressurizing the injection.

5:01 PM

I guess valve gate is the proper term.

I imagine something which contacts the top of the mould and operates a lever to slide the gate sideways

more important is something that the plastic wont stick in place

5:09 PM

like the smootheest mechanisms ive managed to make all failed just because the plastic froze them in place

I really think the mould attachment is one of the most important things to solve for the injection machine. Screwing on the mould takes so long and not nice to take off when hot!

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Joseph

I really think the mould attachment is one of the most important things to solve for the injection machine. Screwing on the mould takes so long and not nice to take off when hot!

Yes commercial machines never have a positive coupling like a screw connection, it's always done just with pressure

5:13 PM

this is what i was trying to explain about a lever mechanism contacting the top of the mould to slide the gate sideways

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5:15 PM

alternatively the same approach could be done by putting that lever the other way up and have it fixed to the crossbeam of the frame to actuate at exactly the right distance

5:16 PM

here is my version of the gearbox, you can see the handwheel hub is fitted to the outer face of the spur gear using a keyway. This means the axle is not transferring any torque. If the hub is made from steel and the gearbox body is aluminium there should be no need for a ballbearing, it will rotate fine with a little grease.

4

here's quite a good video about a slightly different arrangement of gearbox, all in one piece and nice machining guide https://youtu.be/zXrqFZfagrA

mrpete222

Mating the RACK & PINION TIPS #575 tubalcain

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sponsoons

the sliding gates ive tried didnt work,but that could be cuz they were designed without much effort

I was thinking if you put a small heater on the sliding gate to keep the plastic fluid, that could eliminate sticking problems

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Erik72

I was thinking if you put a small heater on the sliding gate to keep the plastic fluid, that could eliminate sticking problems

yes, perhaps hot air would work well there rather than a contact heater

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Timberstar

yes, perhaps hot air would work well there rather than a contact heater

That's a great idea! I was just thinking that the sticking problem was caused by cooling plastic, so a possible solution would be to keep it up at temperature

5:52 PM

I'm sure some experimentation and testing is going to be needed to find the best solution

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Julien in Scotland has been having great success using hot air to heat the whole barrel (on an extruder but would work on any). He said the temperature can be held very stable. He is using a ceramic heater element with a fan blower i believe.

5:57 PM

similar to the Leister handheld plastic welding guns

5:58 PM

https://www.leister.com/en/Heat-Guns

Heat Guns for Plastic Welding, Roofing and more

Leister heat guns and hot air blowers are ideal for plastic welding, shrinking and forming thermoplastics, as well as for drying paint, varnish and much more. Thanks to their powerful hot air blower, as well as various nozzles and attachments, Leister’s professional hand tools are always reliable.

@Joostie I've built this injection molding machine back in 2016/2017. Very loosely based on the Precious Plastic injection. It includes a clamping unit as well. Feel free to visit, i'm based in Zwolle

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Timberstar

Julien in Scotland has been having great success using hot air to heat the whole barrel (on an extruder but would work on any). He said the temperature can be held very stable. He is using a ceramic heater element with a fan blower i believe.

Cool stuff, can you invite him? Or do you know where we can find any pictures of his design? Sounds really cool, I noticed a lot of people already use hot air guns to heat the nozzle of the existing PP injection to improve plastic flow

9:22 AM

With this method I'm really curious how you would keep the heat from escaping, do you know @Timberstar ?

Joostie

Cool stuff, can you invite him? Or do you know where we can find any pictures of his design? Sounds really cool, I noticed a lot of people already use hot air guns to heat the nozzle of the existing PP injection to improve plastic flow

Just a simple heat shield I think, nothing fancy, just a sleeve which directs the flow of air around the outer surface of the barrel. Maybe with a slightly narrowed exit hole to increase the air pressure a bit. I should get him to explain it really, will give him a shout

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Hey guys, does anyone have contact details from Precious Plastic Melbourne? (EDIT: fixed, thx!) (edited)

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9:57 AM

Their official channels don't really get me in touch

For the nozzle -> Mould engangement a spring-loaded engangement works very well. Use it on my machine for 3 years without issues. The main question there is if you want to design around a sliding mechanism that is under 250°C heat or if you separate it a bit from the barrel itself. In both cases the assumption is that the: total spring load << injection pressure which can be achieved by reducing the: nozzle diameter to << barrel diameter

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10:10 AM

Machines from A.B. went for the single-spring design, which might be enogh, But I assume it will go with a less compelling / save movement

10:13 AM

Every kind of manual pushing up the mould saves you <100€ in parts and costs you 2€ every time you push up the mould by hand ;D

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10:16 AM

The only safety issue is if the mould is not placed correctly under the nozzle or if the mould-nozzle surface is damaged, plastic could splash outside.

Cool stuff, I've seen a lot of similar designs to this principle and they seem to work quite good. Just a question: within the PP community I think the 'threaded gaspipe'-mould connector is still like a standard right?

1

Yes - if it would be for a cheaper version I would still stay with it due its a very reliable and safe design - just not fast to operate. Generally there are two standards worldwide you can fit everything onto G/R/BSP pipe threads (fit all between each other) and the NPT for the US market. There are also (expensive) adapters between these two standards. On the machine side you can adapt it with a cap/plug and bolt a cap nut inside as nozzle. On the mould side I make adapters that fit both systems - so are interchangeable between both machine types. (edited)

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Joostie

Hey guys, does anyone have contact details from Precious Plastic Melbourne? (EDIT: fixed, thx!) (edited)

I invited them here.. they said they'd join soon. I'll ping them

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Fritz @easymoulds

Yes - if it would be for a cheaper version I would still stay with it due its a very reliable and safe design - just not fast to operate. Generally there are two standards worldwide you can fit everything onto G/R/BSP pipe threads (fit all between each other) and the NPT for the US market. There are also (expensive) adapters between these two standards. On the machine side you can adapt it with a cap/plug and bolt a cap nut inside as nozzle. On the mould side I make adapters that fit both systems - so are interchangeable between both machine types. (edited)

would there be a way to make the conical design cheap? Seems like people like that design better

@Joseph Would say depends pretty much on the design goals and the target price of the machine? The cheapest option is to have a cap nut with a hole drilled inside as a nozzle. (1€) And then you can decide how to engage with the mould: 1.) Push it on by hand, 0€ but no pressure 2.) Make a fixture/car jack attachment, 10€+ and the time to operate it for the user + risk of plastic cooling down while engaging the mould 3.) Make the barrel movable like shown above so the injection stroke automatically engages the barrel to the mould ~50€+ 4.) Movable barrel + automatic plastic stream regulating nozzle that blocks the plastic from dripping ~300€+ (talking in parts/machining prices) The time saving pays of somewhere in between an hour and a week of operating the machine depending on the underlaying salary

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2:24 PM

Measured cycle time of threded nozzel to auto-engaging nozzle increase is about 50% - tested back in v4 with carabiners by @acoira ^^ (edited)

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With my machine, using a clamping unit I just keep the nozzle pushed to the mold all the time. Don't we want to use a clamping unit? Not having to release products by undoing bolts of the molds saves so much time (edited)

How do you control the plastic flow at your machine when the clamping system opens? @Peter-Bas

I never had any trouble with leaking plastic from the nozzle. The sprue hole diameter I use varies betweek 4 - 6 mm and plastic doesnt flow out of it much with those diameters I guess. It's viscous enough. Making sure the plunger is retracted while releasing the product also helps. (edited)

3:13 PM

The interface between my nozzles and molds is just like with industrial injection molding machines. A round nozzle with a slightly smaller radius compared to the radius of the sprue

Cool, was wondering about that also - probably only a real problem for screw based machines where they feed in the plastic and pressure is built up

3:17 PM

I think the big gap in price if you design the moulds with ejector pins (=some sort serial production) or have a system where you eject the part outside of the machine and only "place" the mould in the machine. Also some steps up in saftey concers there I assume

With industrial injection molding the screw is usually retracted (So called decompression) after dosing for a shot (happens during the cooling phase with the product cooling inside the mold. This is done to prevent leakage from the nozzle.

3:24 PM

I don't have an ejector mechanism in my machine. Would be nice to have though. I tend to use pliers to remove the product out of the mold. Usually I grab the sprue. Works okay for simple products. Having a ejector system would allow the machine to run automatically which is nice to reduce operating costs significantly in areas where labour is expensive.

@Fritz @easymoulds you mean having a nut like this with a small hole in the end? how would you make the chamfer in the mould if this is round, not conical??

That was the idea behind it -> you want the most possible pressure on the smallest surface geometry = good sealing against splash. If you have a sphere and a concial hole the intersection between both will be only a line -> so all the force applies to this line. The sphere so to say rests in the countersink of the mould (edited)

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5:06 PM

You can get them with fancy geometries too, but never felt like needing one

Also smallest surface geometry = the least amount amount of heat transfer between nozzle and mold

but to have a good sealing its better that the counterpart (the mould) has the same shape than the nozzle right? how can this be achieved with a round shape? what about this kind of nozzles? They can have pretty small inner diameters (edited)

https://www.mouldshop.nl/producten?GroupID=gg04_10&ProductID=3828

NEUSTIP STANDAARD

Standaard Neus Tip, Eenvoudig en snel wisselen van de neustip om optimale afstemming met de radius en boring van de spuitbus in de matrijs te komen.

5:50 PM

https://www.hasco.com/nl/Z/aanspuiten/aanspuitbussen/p/Z511_d2xl1xd1xsr1

Z511/d2xl1xd1xsr1 | aanspuitbussen | aanspuiten | Z | Productca...

Spuitbus

5:52 PM

Lots of those parts are standardized for injection molding and not too expensive in my opinion. May be worth while. Companies like Hasco or Meusburger offer a large array of standard parts for injection molding

Black= Mould, Red= Line contact

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Carolina

but to have a good sealing its better that the counterpart (the mould) has the same shape than the nozzle right? how can this be achieved with a round shape? what about this kind of nozzles? They can have pretty small inner diameters (edited)

Would work I think, but would break faster if you push this thing with 500kg force into a mould (edited)

Fritz @easymoulds

Black= Mould, Red= Line contact

Works great with the spherical nozzle (i use one with 6mm inner diameter), all my moulds just need a small chamfer (easy and cheap). @Carolina @Joostie

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Fritz @easymoulds

Black= Mould, Red= Line contact

Thx Fritz this is a really clear explanation!

10:38 AM

On a different topic: Did anyone come across ways to make the rack and gear on the Arbor-style machines a bit cheaper? I found they can cost between 300-500$ which is quite a lot.

10:38 AM

Like cnc-ing it yourself/cheap alternatives/even stacked laser-cutted parts?

What is the target price in parts currently?

Fritz @easymoulds

What is the target price in parts currently?

I don't really have a target price yet, just wondering what alternatives there are out there

Thomas Peterberns | Johannplasto

Works great with the spherical nozzle (i use one with 6mm inner diameter), all my moulds just need a small chamfer (easy and cheap). @Carolina @Joostie

I think its better to have the "red line" (hole in the nozzle) smaller then the hole in the sprue. Otherwise the chamfer will for an anti-release feature when it cold

11:26 AM

Peter-Bas

I think its better to have the "red line" (hole in the nozzle) smaller then the hole in the sprue. Otherwise the chamfer will for an anti-release feature when it cold

Correct, I always design it like this. Can share a 3D-Cut later

4

Joostie

On a different topic: Did anyone come across ways to make the rack and gear on the Arbor-style machines a bit cheaper? I found they can cost between 300-500$ which is quite a lot.

can you share the link of the gears you where looking at?

Joostie

I don't really have a target price yet, just wondering what alternatives there are out there

A bit hard to design around it then I think - its good to have a target user first otherwise you get lost anywhere in between hobby users that just want to experiment and professional users where reduction of cycle time is the only goal.

Fritz @easymoulds

A bit hard to design around it then I think - its good to have a target user first otherwise you get lost anywhere in between hobby users that just want to experiment and professional users where reduction of cycle time is the only goal.

ideally the material costs of the machine shouldnt go over 600 euros (just material) (edited)

Joostie

On a different topic: Did anyone come across ways to make the rack and gear on the Arbor-style machines a bit cheaper? I found they can cost between 300-500$ which is quite a lot.

for simpler applications(it was for a large hatch) ive just plasma cut it in the past (edited)

11:56 AM

plasma/gas for bigger parts is both cheap and accurate

11:57 AM

however it had a bit of slop(it was cut manually) but for that application it was perfectly fine

11:57 AM

so plasma/laser and then stacked seems like a good option to me

11:58 AM

something i really want to try is an angle grinder,in the past ive been able to hold fairly good tolerances with it,the only complain being the time it takes

Carolina

ideally the material costs of the machine shouldnt go over 600 euros (just material) (edited)

And Imo that would already be a pretty high target if the goal is to "mainstream" the machine

vamatis

And Imo that would already be a pretty high target if the goal is to "mainstream" the machine

Hi vamatis - curious what you think a better price point would be?

Joseph

Hi vamatis - curious what you think a better price point would be?

I honestly don't have a good answer for you there haha. I would say the cheapest possible probably. But in my opinion staying under 500, maybe 300 (although that is very unlikely which I totally get) would simplify access. When you hear 300€ it's like close to hundreds. When it's 600 you get closer to 1000€ standards in the subconscious mind imo and it's a way stiffer jump (as an example, that is almost half of the minimum salary here in France haha)

vamatis

I honestly don't have a good answer for you there haha. I would say the cheapest possible probably. But in my opinion staying under 500, maybe 300 (although that is very unlikely which I totally get) would simplify access. When you hear 300€ it's like close to hundreds. When it's 600 you get closer to 1000€ standards in the subconscious mind imo and it's a way stiffer jump (as an example, that is almost half of the minimum salary here in France haha)

tbh that cheap is possible,however at that point,you'll need to target very specific categoryies,produce in quantity or the main thing being a massive drop in quality

7:44 PM

most machines that ive built have been abt 20-40% cheaper than their western build cost,since not only could i find a cheaper range of parts,its just that im in a cheaper place

sponsoons

tbh that cheap is possible,however at that point,you'll need to target very specific categoryies,produce in quantity or the main thing being a massive drop in quality

Well yeah of course but I meant keeping the same architecture/deployment methods. Of course producing in quantity would drop the price a lot but I was talking about keeping the same "buy parts and do it yourself " approach

the simplest way imo is making things very common,so using more commonly used parts,

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vamatis

Well yeah of course but I meant keeping the same architecture/deployment methods. Of course producing in quantity would drop the price a lot but I was talking about keeping the same "buy parts and do it yourself " approach

the main problem with that is there are limits to how much you can drop the simplicity before it stops working

7:46 PM

ive made machines where my tool machine cost was lesser than the predicted build cost for the machines,however those meant a massive drop in quaility and a machine that had to be nursed into working

7:46 PM

you had to go quite easy with it and know the limits

Yes of course that's also true

this is how i thought to build the rack and spur gearbox, trying to make it as simple as possible to machine. The blocks are 30mm aluminium.

12:10 AM

the brass bolt sleeves keep everything aligned

12:12 AM

the big holes are 70 and 60mm so need to cut with a 4-jaw chuck on the lathe probably

12:14 AM

handwheel hub couples to the outside of the spur gear with a keyway

12:14 AM

16T mod 3

12:19 AM

https://www.bearingboys.co.uk/Metric-EN8-Gears/SS3016B-30-Mod-x-16-Tooth-Metric-Spur-Gear-in-Steel-68469-p

https://www.bearingboys.co.uk/Metric-Steel-Racks-20-PA/SR30305-3-Mod-x-30mm-Wide-Steel-Rack-x-05m-Long-160923-p

force_calcs.txt

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@Timberstar, 500N isn't sound considering a typical transmission ratio of 1:1 regarding an arbor. 500N is the same as holding 500 apples with one straightened out arm, according to definition of one Nm. 500N would make sense at a 50cm leverage though (aka 'Maximum power, optimal load and optimal power spectrum for power training in upper-body (bench press)', or similar articles). Speed & handling is important, 22T+ mod at 2.5 is getting you closer to the sweet spot, and in special occasions, 1:1.5 ( 2 gears), even further, assuming your setup is right on.

Accumulated system frictions are easy to overcome at 60cm+ L @ 4x25mm solid sticks, one little tip gets you back on the plunger's home (re-fill), works great the same way back too., optimal hub height is 1.2m

yea 500N would be hanging on the thing with all a person's body weight. but that gives 5000 psi which is about 5x what's needed. A well as the higher gear ratio, I decided on the 16T because it's cheaper and the size makes the rest of the gearbox cheaper and easier too

dunno why i use psi there but find MPa hard to imagine for some reason

There's one piece of physics I need checking: For a design like mine, the output force is the injection force but also the mould clamping force, because the barrel moves down to contact with the top face of the mould, which is what holds the mould closed. So... that means the actual cavity pressure will be half, right? Because the mould has to push back on the cavity at the same force which the plastic is pushing outwards... if you get what I mean? In a normal clamping setup that force is delivered by an independent route so there isn't the halving effect. (edited)

also im thinking the handwheel really should have a circular outer rim for safety. I don't want to think about the force calculations of a 900mm steel bar spinning around onto someone's head... actually quite a difficult to manufacture a rim like that nicely

@Joostie can you remind us when the first design review will be according to your planning? would be cool to invite people from here as well

Joseph

Hi vamatis - curious what you think a better price point would be?

Maybe it's intersting to thinks about different point of views for designing. Like optimized for manufacturing / Optimized for purchasing parts / Optimized for simple materials and tools etc. For a factory with fancy equipment like CNC / 3D printing its more cost effective to have a design with less, more complex and standardized parts optimized for "mass" production without much labour. When someone just wants to get started on a hobby basis, using simple tools you'll need a design which can be made with just an angle grinder and a drill for example. Labour costs can be a defining factor in this.

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Peter-Bas

Maybe it's intersting to thinks about different point of views for designing. Like optimized for manufacturing / Optimized for purchasing parts / Optimized for simple materials and tools etc. For a factory with fancy equipment like CNC / 3D printing its more cost effective to have a design with less, more complex and standardized parts optimized for "mass" production without much labour. When someone just wants to get started on a hobby basis, using simple tools you'll need a design which can be made with just an angle grinder and a drill for example. Labour costs can be a defining factor in this.

I had an idea about marketting my machine as 'part-kit', the complicated parts (gearbox, barrel etc) can be manufactured and sold by a machine shop, while the large, heavy parts of the frame can be sourced locally by the customer and assembled with common DIY tools. This would reduce shipping cost, and recycled materials may be used to further reduce cost

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@Timberstar - I am afraid that a spring loaded barrel is just not enough. You can do very simple and small objects but anything bigger than 2 carabiners wants a lot more... You can connect the steel bars with rolled Aluminum on the outer ends, needs just 2 holes on the sticks. (edited)

did you try one?

10:41 AM

with the moving barrel system the injection force is automatically in balance with the clamping force

10:42 AM

Robotdigg has pneumatic ones which use it, seems to work fine, yes these are not for producing really large parts though

Timberstar

I had an idea about marketting my machine as 'part-kit', the complicated parts (gearbox, barrel etc) can be manufactured and sold by a machine shop, while the large, heavy parts of the frame can be sourced locally by the customer and assembled with common DIY tools. This would reduce shipping cost, and recycled materials may be used to further reduce cost

That makes sense, good idea!

Peter-Bas

That makes sense, good idea!

I think it would be cool to have the kit configurable so you can buy just the gear box and barrel, or plus the crossbeams, or plus the posts and base

10:51 AM

and also the electrics seperately

10:52 AM

by breaking the kit up it means people can get started with a small investment and spread the cost over time

10:53 AM

also the plans would be available open source so they can build whatever parts they are capable of doing themselves

10:55 AM

but the main thing is to get people to source their own posts and make their own base, those are just big heavy lumps of metal, its stupid to transport them far when they can be found locally much cheaper

10:55 AM

The dimensions of the posts are also not critical, any old construction beams will do, C section, I section, box section whatever

10:58 AM

Then the only 2 critical dimensions are the width between the posts, which is determined by the length of the crossbeams supplied, and also determines the width of the base; and the distance in height between the crossbeams which determines where you drill your bolt holes in your posts (edited)

I think a persuasive strategy for local groups just starting up would be build the frame and base on their own initiative with minimal funding, the process of doing so will build the group, and the part finished machine can be used to invite funding to purchase the more complicated parts from the machine shop

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11:32 AM

lol the base and posts can double up as an advertising stand -'help us finish this machine'

Joseph

@Joostie can you remind us when the first design review will be according to your planning? would be cool to invite people from here as well

Maybe it's about time I'll give everyone here a general overview of what I've planned for this project ✨ These past weeks I've been gathering info on injection machines, gathering best practices, precious plastic in general and open source stuff. Here you guys are already helping me a lot with your reflections and ideas on current designs out there, so big thanks for that and please keep it coming! Somewhere in the next weeks, I'll compile everything I've learned into a few concept directions and design goals. It would be cool to hear your thoughts on these as well, so I'll share them here too so you guys can react. This will be around April 26, so stay tuned

Next up (finally), the real designing phase will start! I'll share my CAD-stuff on grabcad so you guys can have a look around. This will include quite a lot of iterations, and if all goes well I'll have a final concept/prototype around mid-July. Thanks already, I hope this creates some clarity! TLDR: Concept directions & design goals coming up next weeks, many big thanks for all your help and involvement! (edited)

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azluar

@Timberstar - I am afraid that a spring loaded barrel is just not enough. You can do very simple and small objects but anything bigger than 2 carabiners wants a lot more... You can connect the steel bars with rolled Aluminum on the outer ends, needs just 2 holes on the sticks. (edited)

Yes, and it can get messy for small shots. For more complex cavities, 1-2T pressure is the bare minimum. That keeps the nozzle clean, and entire process stays clean, predictable and repeatable.

Joostie

Maybe it's about time I'll give everyone here a general overview of what I've planned for this project ✨ These past weeks I've been gathering info on injection machines, gathering best practices, precious plastic in general and open source stuff. Here you guys are already helping me a lot with your reflections and ideas on current designs out there, so big thanks for that and please keep it coming! Somewhere in the next weeks, I'll compile everything I've learned into a few concept directions and design goals. It would be cool to hear your thoughts on these as well, so I'll share them here too so you guys can react. This will be around April 26, so stay tuned

Next up (finally), the real designing phase will start! I'll share my CAD-stuff on grabcad so you guys can have a look around. This will include quite a lot of iterations, and if all goes well I'll have a final concept/prototype around mid-July. Thanks already, I hope this creates some clarity! TLDR: Concept directions & design goals coming up next weeks, many big thanks for all your help and involvement! (edited)

Thanks for the update @Joostie Looking forward to the event. Feel free to post here if you have work-in-progress designs, behind the scenes, doubts or things needing feedback

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Hey @Joostie, I also designing a new Arbour Injection machine for my workshop and made a simple calculation for the gear. It seems very easy to get a much higher injection force than with the lever injection machine (but the smaller the gearwheel, the more you have to rotate;)). My goal is to have the same force like in my current injection machine (It works great;)), a not so big gearwheel to have a small gearbox and less than 1/2 rotation for 35g plastic. Maybe you guys can have a look over the data and check with you experience and machines. If you need the Excel-File @Joostie , let me know. (edited)

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Thomas Peterberns | Johannplasto

Hey @Joostie, I also designing a new Arbour Injection machine for my workshop and made a simple calculation for the gear. It seems very easy to get a much higher injection force than with the lever injection machine (but the smaller the gearwheel, the more you have to rotate;)). My goal is to have the same force like in my current injection machine (It works great;)), a not so big gearwheel to have a small gearbox and less than 1/2 rotation for 35g plastic. Maybe you guys can have a look over the data and check with you experience and machines. If you need the Excel-File @Joostie , let me know. (edited)

Very cool stuff Thomas! Right now i'm coming to pretty much the same conclusion: about 1/2 rotation for 40 grams. Please do send over your excel, would be great to check out!

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Very clever design force-wise I think @Thomas Peterberns | Johannplasto . Just in manner of material use of laser cutted sheets it has a bit room for improvement. But reduces the number of parts also significantly, makes sense

About the arbor development in general, keep in mind that not only the input force matters, but the speed of the injection as well! As cool as a high force sounds, if the injection cycle takes 20sec to fully go through - the plastic will be cooled already by then, no matter how hard you push. It may need some practical tests and physical evaluation here to find the sweet spot in design. Regarding the input variables- you cannot use the same input value of "body mass" due to ergonomic factors of the system! -> you cant hang on an arbor press and wait until its done. For the arbor press design actual strength of the user is more relevant than their weight + a solid base or a fixture to somewhere. One reason why the Plasticpreneur machine is a miserable design in regard to ergonomics of the injection wheel, due it is very hard to even "input" as much force as you can -> no place to really pull with full force. There are two proven designs -> either a classic 3 handle or a 5 handle layout (see image). I assume that this is about the length of the handles at the outside and how fast you can re-grap the next handle? But I assume that this size diameter would not be beneficial to the speed. It may be the case that it even makes sense to consider exchangeable gears/handles for low speed-high force items (small and thin walled) and high speed-low force items (thick walled high volume) (edited)

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Fritz @easymoulds

Very clever design force-wise I think @Thomas Peterberns | Johannplasto . Just in manner of material use of laser cutted sheets it has a bit room for improvement. But reduces the number of parts also significantly, makes sense

About the arbor development in general, keep in mind that not only the input force matters, but the speed of the injection as well! As cool as a high force sounds, if the injection cycle takes 20sec to fully go through - the plastic will be cooled already by then, no matter how hard you push. It may need some practical tests and physical evaluation here to find the sweet spot in design. Regarding the input variables- you cannot use the same input value of "body mass" due to ergonomic factors of the system! -> you cant hang on an arbor press and wait until its done. For the arbor press design actual strength of the user is more relevant than their weight + a solid base or a fixture to somewhere. One reason why the Plasticpreneur machine is a miserable design in regard to ergonomics of the injection wheel, due it is very hard to even "input" as much force as you can -> no place to really pull with full force. There are two proven designs -> either a classic 3 handle or a 5 handle layout (see image). I assume that this is about the length of the handles at the outside and how fast you can re-grap the next handle? But I assume that this size diameter would not be beneficial to the speed. It may be the case that it even makes sense to consider exchangeable gears/handles for low speed-high force items (small and thin walled) and high speed-low force items (thick walled high volume) (edited)

To have a feeling for the speed I think the calculation of the rotations/volume is good for a start. So I calculate how big my gear circle of action (d) has to be if I like to inject 70gramm with one rotation (see picture). With my actual machine I inject 110gramm with one rotation and have the feeling to inject a bit less and have more power. When I see videos of the PlasticPreneur-Machine I think they inject too less gramms/rotation and you have to turn a lot to get bigger moulds full. I used the same "body masses" for both machines to have a feeling about the maximum possible injection force. So when I inject and the mould is full I hang with all my weight on the lever, just like the people do with the lever injection machine :D. Great idea with the exchangeable gears! I am happy to see a new opensource arbour injection machine coming @Joostie ;):)

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Yes had some clients who struggled due to the gear ratio at the Plastpreneur machines - material cooled way to fast in there. Looking forward for the outcomes here!

10:58 AM

Its mainly on thin walled parts where you push the limits of the machine. The issue is that you have to keep up the high force during the full process, which is really challenging of course. But also can be avoided by thicker walls in most cases, not too many designs require that.

Thank you so much for your input @Fritz @easymoulds and @Thomas Peterberns | Johannplasto its super interesting to read your conclusions based on your experience with different arbor injections designs that are out there! Looking forward to see the first iterations from @Joostie !

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https://www.instagram.com/p/CckNtO9IxUJ/?utm_source=ig_web_copy_link

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What do you do to make your injection machine stable?

Thomas Peterberns | Johannplasto

Correct, I always design it like this. Can share a 3D-Cut later

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@Thomas Peterberns | Johannplasto and @Fritz @easymoulds To continue about injection speed: This is ofcourse very dependent on mold geometry and material specs, but do you have an indication on what injection times/speeds you usually work with? Is there like a rule of thumb?

@Joostie The industry uses speeds of usually under 10sec. the required speed however is strongly related to the wall thickness of the part. This image shows a bit the estimated time ranges that work. However they are from a chart of screw based machines with much higher injection forces. Not fully sure how this would change with our machines - guessing that we usually have around ~30% more time by the designs we do at the moment. (Thicker walls than in the industry recommended values) Something between 13 sec for a full barrel and 2 sec for half a turn should be okay.

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3:15 PM

src: ARBURG Practical Guide to Injection Moulding, 2nd Edition, pp 197

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dadda29993

What do you do to make your injection machine stable?

it really depends on your machine design, some is better to attach to the floor or table some its needed to extend the base to make it more stable, but it depends

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Fritz @easymoulds

@Joostie The industry uses speeds of usually under 10sec. the required speed however is strongly related to the wall thickness of the part. This image shows a bit the estimated time ranges that work. However they are from a chart of screw based machines with much higher injection forces. Not fully sure how this would change with our machines - guessing that we usually have around ~30% more time by the designs we do at the moment. (Thicker walls than in the industry recommended values) Something between 13 sec for a full barrel and 2 sec for half a turn should be okay.

Another fun fact about injection molding. Increasing speed of injection lowers the relative viscosity of the molten plastic. So a faster flowing melt is less viscous. Viscosity for thermoplastics is shear dependant

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oO did not knew that! Wondering how a math equation of that would look like

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@Joostie@Fritz @easymoulds@CarolinaIt would be great to get people to report the ratio they are using for their existing gearbox and whether they would prefer it higher/lower. We would need to record the number of gear teeth, gear module, and barrel diameter to calculate cm3 per turn of the handwheel. I'm guessing it's ok to assume 1g = 1cm3 as per HDPE

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5:53 PM

I think the difference between a ID 25mm barrel and a ID 30mm barrel would actually be significant

5:59 PM

While the injection time is important, it can be modulated by the user, from a practical point of view the crucial equation is how much volume you can inject relative to torque on the handwheel. A secondary gear would address this but add a lot of complexity to the gearbox design. (edited)

6:02 PM

Are folks generally looking at a mod 3 rack? I believe mod 2.5 would be the minimum for the forces required

Timberstar

I think the difference between a ID 25mm barrel and a ID 30mm barrel would actually be significant

Right, but increasing the diameter of the barrel would also result the plastic in the center not melting right? Next to that I think it's indeed good to know details about peoples gearbox design, I'll be making an overview of different compositions

9:32 AM

About the barrel diameter: I'm curious if people have experimented with changing this, both in making it smaller to decrease heating time and in making it larger to increase shot-volume. If you did, tell us about your experiences with this!

@Yann made a prototype increasing the diamenter of the barrel to 1.5'' getting as a result 250g per injection. It worked, plastic melted all the way through but by increasing the diameter you also reduce the pressure. So it might be better (if we are looking to increase the capacity keeping the same pressure) to make the barrel longer rather than wider. (edited)

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Yes this was the first PP machine I built. Which was basically the same lever injection from the download kit, but with a wider barrel (with same length). It worked well for what I was doing, which wand bodysurf handplanes, so around 250g, 5mm, paddle for the hand.

11:44 AM

I always let the plastic melt for 20min between injection, but never really tried to reduce this time, as my shredder was also really slow (I was shredding and injecting in parallel). So I can't tell what was the impact on the melting time (all was melted though).

11:46 AM

Another downside of a wider barrel is the pressure loss for an equal force as the surface of the plunger increase. But that is maybe compensated with a faster injection of the same volume.

Joostie

Right, but increasing the diameter of the barrel would also result the plastic in the center not melting right? Next to that I think it's indeed good to know details about peoples gearbox design, I'll be making an overview of different compositions

As far as I understand 25 and 30mm ID are most common, I have heard about problems going larger than that. 30mm diameter would give 7cm3 per 1cm travel so 280cm3 for 40cm travel, compared to 5cm3 per cm for 25mm barrel giving 200

1:20 PM

this would mean more input force required as well as more thermal energy to melt the plastic. The 25mm ID is commonly used because the cheap 35mm heatbands fit ok on that size pipe

1:22 PM

I think for a hand-cranked machine it's better to aim for the lower volume and ensure good pressure

I think this was the one I used : https://www.acier-detail-decoupe.fr/aciers-doux/4166-acier-etire-doux-a37.html so ID=32 and OD=40 because I could find a 31mm bar (no lathe at that time) and 40mm heat band.

ACIER ETIRE DOUX A37

1:26 PM

But I agree, 35mm OD seems better for heat band. You can find other size, but definitely less widely available.

Fritz @easymoulds

oO did not knew that! Wondering how a math equation of that would look like

Lots of integrals equations

Peter-Bas

Lots of integrals equations

And that's just the math. Surface area calculations alone aren't exact or easy to back up. I'd love to see that setups

@all: Next week Thursday 28/04 at 4:00PM CET, we will organize an open meeting in which I'll present my design directions

We will set up a discord call in which @Carolina, @Joseph and me will be discussing my plans, while you can listen in and ask questions & chat in a designated channel. The general plan for the meeting is to discuss:

User research findings

Design directions and goals

First ideas and concepts My goal of the presentation is to inform you about the general direction of the Arbor-press design and for me to check my choices and assumptions. Everybody interested is welcome, I hope to see as many people as possible!

Don't expect any prototypes or fancy renders for this meeting, that will be next time

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Another question: We know the shot volume of the current lever press is quite small (150cm3 barrel, ± 70 actual shot size), but what should we aim for with the Arbor press?

10:47 AM

Bigger = better in this case, but what would people want to make with it?

having a bigger capacity gives you the possibility of increasing productivity but up until a certain point. You could make moulds with more cavities or bigger products, but also you can't make a very big mould either, because you are also limited by the mould radius

11:52 AM

other ways of increasing productivity are by having 2 times the same mould and injecting two times in a row, which with the current capacity is not possible with moulds like the carabiner because there's not enough plastic in the barrel for 2 shots in a row

Joostie

Another question: We know the shot volume of the current lever press is quite small (150cm3 barrel, ± 70 actual shot size), but what should we aim for with the Arbor press?

The bigger is really the better, more design freedom or scalability of production of little things are gold, for example. To me the constraint is the power needed to molten the plastic, to be properly sized for the minimum contract (here in Italy is 3,5 KW per house), so thinking about using at the same time with the shredder in an Injection Workspace, that makes like 1,5 KW power max for the arbor press machine, in this case. All these rough estimates leads to a barrel packed with 6 to 8 heaters. This number of heaters, roughly 5 cm long, leads to a barrel that is like 50 to 70 cm long, plus hopper space, that is something like a 200 grams recycled plastic load. Maybe we can stretch that to 250 grams, i don't know, but the principle i am thinking about is a mechanical/spatial design that optimizes the energetic/thermal possibilities of the build, making the arbor press a more efficient and productive machine, with the same building effort as the non-yet-optimized version and negligible differences in cost of materails for the build

Make sure to mark "interested" in our first open discussion on the arbor press ! https://discord.gg/dBM2W2t6?event=968140005329477632

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i am going to build my first prototype with this guy, a machine to put caps on beer/ wine bottles, i will update the results of this trial here

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blastic

i am going to build my first prototype with this guy, a machine to put caps on beer/ wine bottles, i will update the results of this trial here

nice!!

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blastic

i am going to build my first prototype with this guy, a machine to put caps on beer/ wine bottles, i will update the results of this trial here

this could be useful here mainly for a cheap and effective rack and pinion design, i really don't know how well (bad) this will work though

im very interested to know how that will work! I've heard of people trying with small drill press or with a metal stamping press (no idea how it turned out)

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blastic

this could be useful here mainly for a cheap and effective rack and pinion design, i really don't know how well (bad) this will work though

very interesting, i definitely like the design using the side piece of the crossbeam as the actual gearbox casing, the whole design makes a lot of sense, could be easily copied... I think I would prefer the legs either side of the gearbox but that would be easy to do. Im guessing its only about 1m tall though? and I think the base will want beefing up a little. But this is a great example of reduced part count, it's very simple

2:04 PM

I will try to draw something over the next few days, I can see now how it might be done with very very few parts

Hey everyone, will be doing a bit of housekeeping as part of a Precious Plastic Discord update.. sorry to interrupt the nice flow of the channel

The Arbor Press Work Group is looking to optimize the Injection machine lever design into a Arbor press version which is intended to be documented and distributed open-source through the Precious Plastic academy, so others can build it around the world and address the plastic waste problem in their community. Goals

Research, design, build and document an Arbor press injection machine.
Follow the Precious Plastic design guidelines and CE safety requirements.
Research best practices of design, engineering, material/part sourcing, etc from community members, particularly from those with experience building and using different Arbor Press designs.
Document a final design for this machine following the Precious Plastic documentation structure.

‍♀️Steward The current steward of this channel is @Carolina How it works 1. The steward coordinates, moderates and guides the efforts to get the new Arbor Press design. 2. @Contributor helps with their expertise and knowledge on designing / working with Arbor press designs.

Research The design process of the new Arbor Press Injection machine will be documented here: https://community.preciousplastic.com/research/make-open-source-arbor-press-injection-machine

Rules Same rules as One Army apply so let’s just be nice and respect each other Have fun

(edited)

Precious Plastic pinned a message to this channel. 4/26/2022 3:33 PM

Hello people! Few pieces of information regarding the arbor press call tomorrow. Time: 4pm CET Moderator: @Joseph Technician: @Mattia Agenda topics:

Quick intro and housekeeping - @Joseph

User research findings - @Joostie

Design directions and goals - @Joostie

First ideas and concepts - @Joostie

PP team feedback - @Yann @Carolina

Community Questions/discussion - @Joseph moderates, attendees contribute Questions can be posted in the #archived-arbor-press-dev channel during the meeting. (edited)

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Precious Plastic started a thread. 4/27/2022 4:58 PM

this is what I came up with for a simplified gearbox/crossbeam arrangement

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12:09 PM

the gearbox crossbeam is aluminium plate so it would need stress calculations

12:12 PM

im thinking aluminium to avoid using a massive bearing, the rack definitely needs to slide on alu but making the whole gearbox in alu should ensure everything slides nicely, plus its easier to machine

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Timberstar

I will try to draw something over the next few days, I can see now how it might be done with very very few parts

The toy has arrived

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12:13 PM

it is small

very interesting!!

it also has a stopping strip to hold the rack high

12:16 PM

check the photo of the inside of the tube/hole

12:17 PM

it is small, but its price was 42 euro shipped

incredible

the rack is 26 cm

even if it's too small for your purpose you have a useable rack and pinion there, they are not cheap

yes!!!

i think with some tinkering you have the basis for a neat machine

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i am searchin for a sobstitute rack , until now i found 50 cm rack for 62 euro, i am not sure if purchase it or go on and build a smaller capacity injection machine, just to prototype quickly and learn the working process. What would you say?

for sure try with what you have, you will figure out a lot of things as you go

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Timberstar

incredible

they are Grifo brand machines, you can find them on the principal e-shops. The one owned by the astronaut is pricier though

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Timberstar

for sure try with what you have, you will figure out a lot of things as you go

You are fueling me!!!! thanks!!

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maybe it's worth trying to figure out what forces this setup is capable of, if it's really weak it might not be worth investing too much time into. you could try hanging a weight on the arm and see how much it presses down on a weighing scale, that way you can calcuate the ratio

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12:25 PM

and then try with your arm, to see where it maxes out

Timberstar

maybe it's worth trying to figure out what forces this setup is capable of, if it's really weak it might not be worth investing too much time into. you could try hanging a weight on the arm and see how much it presses down on a weighing scale, that way you can calcuate the ratio

great advice

. when i manage to do the test i will share results

12:27 PM

i am going for an arm test right now

well, i went until 85 kg with little effort, i am trying to document this with a little improved setup

now i managed to measure more than 90 kg pressing only with one hand (the other was taking picture - pressing at max force gave an ERR message on the 150 kg max scale because of the misuse of the 4 sensor feet, i think), sounds ok to me, LETS BUILD . I would like a lot to make the ratio test with the weight in the next future (thankyou @Timberstar , gold advices and designs !!!!) (edited)

Timberstar

maybe it's worth trying to figure out what forces this setup is capable of, if it's really weak it might not be worth investing too much time into. you could try hanging a weight on the arm and see how much it presses down on a weighing scale, that way you can calcuate the ratio

oh nice thats very interesting idea! @blastic let us know how it goes, im very curious

1

Carolina

oh nice thats very interesting idea! @blastic let us know how it goes, im very curious

For sure !!!

2

I hope to see you two in the meeting today?

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1:02 PM

https://discord.gg/dBM2W2t6?event=968140005329477632

luckily I can do it

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1

great!

1

I forgot to post this detail of the rivet used to fix the metal strip that automatically blocks the rack and prevent it from falling down because of its own weight when not in use

Hey guys when possible let's try to use threads and keep conversation on topic

1

Here are the slides for the presentation!

Client_Meeting_v3_compressed.pdf

3.94 MB

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we hear you joost

4:08 PM

i do..

Hello everybody !

I'm leading Recylab in Liège (Belgium. Relocation in France, soon)

️ I'm a mechanic and I have made an upgraded arbor press. You can see it on Instagram (Recylab_lg) There are improvements on many points. I will love sharing my work with the preciousplastic community but I still not found how to share pictures on this channel... Warn me if I'm burning some rules on this chann. Finally, excuse my English, so bad. If someone can be my French intermediary maybe it will be smoother. (edited)

Recylab - Lucas

Hello everybody !

I'm leading Recylab in Liège (Belgium. Relocation in France, soon)

️ I'm a mechanic and I have made an upgraded arbor press. You can see it on Instagram (Recylab_lg) There are improvements on many points. I will love sharing my work with the preciousplastic community but I still not found how to share pictures on this channel... Warn me if I'm burning some rules on this chann. Finally, excuse my English, so bad. If someone can be my French intermediary maybe it will be smoother. (edited)

we're having a live event right now, join to learn the latest! In the meeting-room at the top of the channels (edited)

2

Mattia

we're having a live event right now, join to learn the latest! In the meeting-room at the top of the channels (edited)

My English is to bad to understand and have exchanges in live

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wonderful work Joost ! I knew you would have rocked

4:31 PM

definetly i am a fan of a modular model

4:32 PM

fits better an open source design, to me

4:32 PM

and can grow / change with experience from the user

4:33 PM

parts can be easily mainted/swapped

I love the comparison between the semi-industrial and education. My personal opinion for the design direction is that should be one step more towards the production direction, as we already have an education focused model of the injection machine

4:34 PM

That way the user can step up or down towards the education or production direction

With my open nozzle I just put a block of metal under it to stop oozing - not elegant but works good^^

4:35 PM

One question about the squared rack design - how do you plan to guide it precisely so it does not miss-align with the barrel?

@Joostie I think the nut is very dangerious as it doesnt release the pressure

Yes I was also wondering about safety here

Hey guys nice to meet you all, my main input would be that everything in the arbor press needs to be designed around the spur gear. Its one of the most expensive parts to buy and the size and number of teeth are critical, also the way that the torque is transmitted to the gear from the handwheel ie the coupling

1

One thing i would like to have integrated in the machine is a little fumes extractor / carbon filter, since it already has electricity. It could be more an electrical box redesign than a frame redesign, though

Amazing work @Joostie . Am wondering: It sounded like you found the spring-toggled table as a really good solution for clamping - you think it's too complex to fabricate worldwide or why did you choose the springloaded barrel in the end for the way forward?

feeding of the machine is better from the side, the plunger should stay within the barrel all the time to keep good alignment

1

@Kat all of my clients with the Plasticpreneur machine failing with this design. Everyone struggles with it in production.

1

The spring load on average is way lower than the injection pressure. If the spring would be stiff enough, you would not be able to toggle it by hand anymore (with an ungeared design)

Fritz @easymoulds

With my open nozzle I just put a block of metal under it to stop oozing - not elegant but works good^^

I use a hammer

2

Thomas Peterberns | Johannplasto

I use a hammer

I always notice that in your pics/videos

Fritz @easymoulds

The spring load on average is way lower than the injection pressure. If the spring would be stiff enough, you would not be able to toggle it by hand anymore (with an ungeared design)

useful to know your experience with that

@Joostie I think increasing the barrel diameter is an exponential cost increase. Larger barrel > More Material cost > More expensive heat bands > bigger gear > longer leavers. May drift the cost a lot in the end, but not totally sure.

Rory - Sustainable Design Studio

@Joostie I think increasing the barrel diameter is an exponential cost increase. Larger barrel > More Material cost > More expensive heat bands > bigger gear > longer leavers. May drift the cost a lot in the end, but not totally sure.

i agree, also higher thermal energy requirement and longer heat up time

Getting larger pressure actually makes it easier to inject finer objects without the need to increase volume (edited)

Mattia pinned a message to this channel. 4/28/2022 4:46 PM

1

Same I cant enable

re. the rack and gear, I think Module 3 is the best size, Mod 2.5 would be just about big enough

@Rory - Sustainable Design Studio @Fritz @easymoulds just gave you speaker right, you can talk now

4:54 PM

ping me if you wanna add your comments live

Still cant :/

4:55 PM

Only can turn on my video

i am going for 16 teeth, 26 gives a more comfortable ratio for injecting but the gear is a lot bigger so bigger gearbox housing, and of course more expensive

Giving it too much pressure is also dangerious

4:56 PM

it feels too easy to add a tonne!

multiple gears is a nice idea, i will work on that

You could have a tilting gear bearing so the spacing is flexible

Sorry, have to go:/ Also wasn’t able to join from the beginning:/ is this recorded?;) Great work @Joostie See you guys! ✌️

Joostie

Here are the slides for the presentation!

@Thomas Peterberns | Johannplasto presentation here - nope unfortunately not recorded

@Rory - Sustainable Design Studio

5:02 PM

there are better quality ones but couldnt find the picture

The left solution starts from ~1k€ in parts

Fritz @easymoulds

The left solution starts from ~1k€ in parts

very interesting

(hydraulic clamping)

@Carolina Nice, and simple coool!

they are pricey but reliable https://www.tcdirect.nl/Default.aspx?level=2&department_id=180/26

TC Direct voor Thermokoppels, Thermokoppel Kabels, Pt100 Sensoren...

TC Direct is de distributie afdeling van de TC groep die is gespecialiseerd in temperatuurmeting, regeling en kalibratie. TC heeft filialen en productlocaties in de UK, Europa , Verenigde Staten en Australië.

Cheers

The machine could be design to pop in a readymade clamping as an addon from a machine maker

@Joostie Would be intresting to see where you think the current arbour designs sit on your spectrum.

5:05 PM

Also what your goal price is for this?

The main critical thing is of course our input force, if we agree on 350N thats a good benchmark, from that we can calculate the pressure which can be achieved, that will determine the maximum cross section and length of the cavity and therefore the maximum outer size of the mould which will determine the minimum width of the frame. My current revision is only 180mm between the posts, so only quite small moulds but I think that's realistic for a hand operated machine

1

Timberstar

The main critical thing is of course our input force, if we agree on 350N thats a good benchmark, from that we can calculate the pressure which can be achieved, that will determine the maximum cross section and length of the cavity and therefore the maximum outer size of the mould which will determine the minimum width of the frame. My current revision is only 180mm between the posts, so only quite small moulds but I think that's realistic for a hand operated machine

would you like to join the conversation?

hm its easier for me to type to be honest

Timberstar

hm its easier for me to type to be honest

ok no problem!

that sounds fun

Thx everyone!

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3

Thank you everyone, amazing presentation and amazing participants !

Within the prototyping, make sure to do testing on the ergonomic features maybe with a variation of users how much force they can apply- could be that you also measure your force and get suggested a machine that fits you best ;D Might also be that you find papers on that.

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Thankyou, incredible community experience

1

This is a tool which can help figure out what size of part we can inject with the input force we have. Just need to look up the injection pressure for whatever type of plastic. https://www.custompartnet.com/calculator/clamp-force

Clamping Force Calculator

Calculates the clamping force for injection molding and die casting. Clamping force indicates the amount of force that the clamping unit can apply to the mold to keep it securely closed during the injection of the molten plastic.

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5:18 PM

(clamping force is equal to injection force)

Thanks everyone for you participation and great feedback!

Hope to keep seeing you around here once we get to see the first drawing. Looking forward to the first prototype! PreciousPlastic

6

3

Yesterday was the first such event we run on Discord. We had a lot of fun. But I am more curious about the experience of everybody else that joined. Was it useful? Was it fun? Was it messy? Was the audio OK? Anything you liked/disliked? Post your feedback in the thread so we can make the following events better for everyone.

Joseph started a thread. 4/29/2022 8:42 AM

Carolina

used /poll

What 3D modeling software people use the most here?

Fusion 360

Solidworks

9

5

Freecad

2

1

Also

and

OpenSCAD

3

@Joostie Sorry i couldn't make it to the meeting. Went trough the slides, you did a good job so far! As a semi-industrial user I might have some remarks on the functional specs, but that might be a topic for later (edited)

2

Timberstar

you can click on the emoji

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Heya, does anyone have any data on experimenting with insulation? I'm curious about the possible power savings that adding different types of insulation could save!

Open source CAD is just not there yet where open source polygon programs (like Blender) are. OpenSCAD is awesome if the output is 3D printing and you need customized solutions to the user. (edited)

I never ever had any problems to either exporting STL's for 3D-printing or producing gcode for my cnc with freecad. I would like to know why you think that freecad is

(edited)

Joostie

Heya, does anyone have any data on experimenting with insulation? I'm curious about the possible power savings that adding different types of insulation could save!

Never measured it myself. Meten is weten I guess

1

Joostie

Heya, does anyone have any data on experimenting with insulation? I'm curious about the possible power savings that adding different types of insulation could save!

That's a really good topic with the increasing cost of energy because of war.

Joostie

Heya, does anyone have any data on experimenting with insulation? I'm curious about the possible power savings that adding different types of insulation could save!

Insulation to me it is also crucial in optimizing the workflow during production. For example you could have shorter injection sections that repeats multiple times during the week (because you can shorten the heating starting time), allowing thus more flexibilty in scheduling the working time, thus leading to optimized production and better economy / working organization and usabilty of the workshop. In brief that insulation does not only optimize power consuption (and its bill) but also it optimizes the working time and scheduling of the injection operator (lowering workpower expenses). Just thinking out loud

1

Hey guys, first CAD stuff will drop somewhere next week! In the mean time I'm curious to your thoughts on the power needed for the band heaters: I'm seeing people use 240W heaters, do people have experience using other power ratings? Obviously higher power = quicker melting times, but what would be the max / minimum needed? Just curious for practical experiences on this!

3

recently uploaded on the Bazar https://bazar.preciousplastic.com/machines/injection/injection-fully-built/inyectora-arbor-fully-built/

Inyectora Arbor Precious Plastic

Inyectora Arbor Precious Plastic Reciclado Plastico

2

1

Mattia

recently uploaded on the Bazar https://bazar.preciousplastic.com/machines/injection/injection-fully-built/inyectora-arbor-fully-built/

They use loudspeaker-connections for 220V mains??? As we can read on the website of the manufacturer NEUTRIK : "speakON is not to be used as an AC mains or power supply connector!" They should at least use powercon connectors. (edited)

1

First CAD-stuff and drawings coming later today ✨

7

4

2

Hey guys! Below you’ll find the link to the partnerspace on the GrabCad workbench where we’ll keep posting the latest model of the Arbor-Press development. Check it out and let us know what you think! https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC You can comment both in this discord channel or in the partnerspace, although the discord is probably a better place for discussion. (edited)

GrabCAD

The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

4

2

11:54 AM

So.. what are we doing again? For the development of the Arbor Press, the main design goal is to make the machine as accessible and buildable as possible in all global contexts. Practically, this means the following:

No CnC-ing
No lathe-work
(almost) No welding

In the coming time we’ll see how feasible these goals are, but they provide a good starting point.

11:55 AM

What’s happening in this version? For this first update, I mainly worked on the suspension of the rack and spur gear. These need to fit together just right to ensure a proper working machine. As this is pretty difficult without a CnC, the current solution is using two eccentrically round bars which the user can twist to adjust the rack position. Not sure if it would work, so let us know your thoughts! This video shows how this would work.

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11:55 AM

Perpendicular to this, the rack fits between two square bars with 0.5mm of slack so it can move up and down easily. The spur gear (mod3, 22 teeth) is attached on the main axis by a bolt and is suspended between two pillow-block bearings, which I think are relatively easy to get. Both this axis and the eccentric round bars are the same diameter and material as the plunger, so they can be bought as one piece.

11:56 AM

How will we go from here? In the coming weeks, more of these updates will come your way. You’ll always be able to see the latest in the partnerspace on GrabCad. Alongside, I’ll start building some prototypes to validate ideas. And that’s about it for now! Good to know: these are the first steps, so a lot of stuff is unfinished (like the frame, injection unit, handlebars, etc.). Let us know what you think, don’t be shy ✨ ✨

Cool, Those pillow blocks have room for adjustment already. So I would choose either adjusting the pillow block or having an excentric with fixed shaft position. To many adjustment locations just add to complexity in my opinion. The forces pushing against the excentric shafts will be considerable so make sure there is a bearing surface in between there (either ball / roller bearings or sliding). Check the prices of pillow blocks, they can be expensive. You could consider using standard ball bearings of (even better in my opinion) sliding bearings for the shaft. Sliding bearings are very suitable for high force / slow movement applications. The only thing to look out for is surface roughness and fit when using that

4

Agreed, I think a sliding bearing would be a good idea. Any ideas for alternatives to pillow blocks?

is the adjustment in order to be able to change the gear size?

If you use 60x30 profiles instead of square profiles it may save you all the cornor-plates in the design? Weights more but reduces the assembly efforts. Would be the question where is the weight with the current design and if there is a speced limit to it? The rack is guided with rollers in one direction, how is it guided in the other direction? (edited)

ideally the machine would weight under 30 kg. but its not a huge deal if it weighs more. The advantage of it being less than 30 kg is that people can ship it with regular shipping services (if they sell the machine alone ofcourse)

Fritz @easymoulds

If you use 60x30 profiles instead of square profiles it may save you all the cornor-plates in the design? Weights more but reduces the assembly efforts. Would be the question where is the weight with the current design and if there is a speced limit to it? The rack is guided with rollers in one direction, how is it guided in the other direction? (edited)

In the other direction (see image) its guided by the profiles of the frame, it has about 0,5mm of clearance. I think this would be okay as there are no loads in this direction, but testing will tell I guess (edited)

The question is more if steel-steel will create abrasive (metal dust) that ends up in the injection barrel/product. Would design a bearing surface at min. But yes good to go for testing I think.

1

What kind of bearing surface do you mean?

From a business perspective I would agree the reduced weight is big advantage bc of the shipping

yes unless it's strictly necessary for mechanical reasons

in my opinion there should be a keyway on the axis and gears. Using a pin is not viable since the pin will ware down over time leaving bits of metal, making the gear impossible to take apart from the axis. (edited)

1

Here is some comment form my side : On the gear area : 1/ I have some doubts about the eccentric round bar. From the CAD, it look like normal round bars, with a decentred threaded hole, not a roller. This will create a lot of friction, as the gear will heavily push against these. I would see more roller there, with a adjustment mechanism somewhere else ? (edit - I saw you changed for roller on your latest version) 2/ I agree with Fritz on the lateral adjustment, at best it will just scratch the paint and get rusty, at worst start to wear metal. Maybe you could use some teflon guide there ? 3/ The gear axis has no keyway, but a pin. I understand the no machining, but this will becomes a weak point after some uses. 4/ You are using a gear with a hub, if you change for a keyway system, you would not need this hub, and this would simplify alignment of your gear with the rack. 5/ Overall I feel this gear area very open. There is still a way to enclose it later for safety/aesthetic, but you could also use this enclose to built a gearbox : this can be laser-cut, which will facilitate adjustment, as drilling will be precise enough so you will probably not need it. You could also use laser cut sheet to incorporate bearing in these gearbox walls. Precision will not be enough for press-fit of a bearing, but you can create a 3 plates wall clamping a bearing inside. Or use UCFL bearing as on the shredder box. A box will also allow a better fit of the rack with some teflon or copper sliding system. (edited)

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1:18 PM

On the general structure : 6/ I have some doubt with the strength of 30x30 beams with this length of flexion. Did you run some calculation ? 7/ The laser cut plates seams to have a 2mm thickness in the drawings, I also doubt longevity in that case. 8/ Overall, the frame look a bit "not aligned", I would maybe remove the constrain of "no-welding" and "only 30x30 beams". So the legs can be centered, or only on the outside. The top and bottom beams can also be created in laser cut sheets welded together to they are centered and already include feature to incorporate the gear box and the injection tube etc... Drilling a lot of holes on 30x30 beams will be very time consuming for not DIY cases (unless access to tube's laser cut, but this is still less accessible than sheet laser cut). (edited)

1

Carolina started a thread. 5/25/2022 1:31 PM

Thanks a lot all! Just to summarize my thoughts on all the input: On the gear-rack positioning: The engagement of the gear and the rack should be quite precise to prevent wear on the gear teeth. As I thought this might be difficult to pull off by the builder, I came up with the idea of the excentric bars. They allow you to adjust the engagement by turning the excentric bar and fixing it once the connection is just right. However, I ditched this idea as it's probably overly complicated and I found another solution (will post that later). On the lateral adjustment: Telfon or something similar is a good idea and probably necessary, I'll look into this! On the gear keyway: I agree there are quite some advantages to having a machined keyway, however I think it's quite costly and will probably be an obstacle for many builders. This is something we need more discussion on: What would this generally cost, and are there any alternative solutions? On the frame: As I said above, the frame is currently just there as a base for the gear suspension and is very much not anywhere finished. I'll work on that in next versions. On the idea of a laser cutted gearbox: Good suggestion, I'll look into it! I didn't take this direction until now as I'm afraid the positioning of the axis and gears will be quite hard, but that might be solvable.

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There's a lot going wrong here. I don't really know where to start. You seem to be trying to find new solutions to problems which either don't exist or have already been addressed in a better fashion. For example why do you need a pillow block bearing? The rotation is extremely slow, there's no need for any kind of bearing. Why put rollers behind the rack?

Here again is the gearbox I designed for very simple construction. It would still require a mill to make it.

10:06 AM

It might be possible on a drill press if the blocks were already faced

10:10 AM

I don't think it's a good idea to try to avoid using proper workshop machines to build the gearbox, and using some other kind of arrangement like yours with the horizontal rollers will just create further design challenges. The right solution needs to be very simple that doesn't neccessarily mean it will be simple to make accurately .

Timberstar

Here again is the gearbox I designed for very simple construction. It would still require a mill to make it.

This is the kind of gearbox I was thinking about. When you made some what kind of tolerance you are aiming for to clamp / guide the rack ? (edited)

10:20 AM

I also agree, there is no need to absolutely look for low budget building equipment there. The lever injection is already a good option if you only have a grinder available.

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Yann

This is the kind of gearbox I was thinking about. When you made some what kind of tolerance you are aiming for to clamp / guide the rack ? (edited)

My hidden question there is : is rectifying the surfaces on a mill absolutely necessary, or laser cut tolerance could still achieve a satisfactory result. (edited)

There are clearance guidances in the spec sheet for the pinion gear for mod 3, but in real life I would cut it to the nearest mm and adjust if necessary. The block which the rack slides against is small, so could be remade quite easily if necessary. But critically the gearbox is made of aluminium, so the steel rack will cut its own channel after a few days of use. Steel against aluminium slides very nicely- before ballbearings were invented, pillow blocks were just aluminium cast around the shaft.

10:32 AM

A mill would mainly be necessary to face the blocks so that they sandwich together accurately, but if they can be found already flat enough then maybe it could all be done on a drill press. You would need a circle cutting head though, for the larger holes. They could alternatively be cut on a lathe with a 4 jaw chuck.

10:33 AM

A lathe would also be necessary to make the handwheel hub

10:36 AM

in this pic i used brass bolt sleeve inserts but a better solution would be threaded dowel pins to maintain accuracy of position of the blocks

10:40 AM

On a drill press you would need to clamp the assembly together and drill the 4 corner holes through all the parts at the same time. Even then the accuracy might not be good enough for the parts to fit if they get turned around, it would need to go together the same way each time. Mill would be best.

10:44 AM

However, my design is not the simplest possible with a mill. The classic style of rack and pinion is only 2 parts. https://youtu.be/zXrqFZfagrA

mrpete222

Mating the RACK & PINION TIPS #575 tubalcain

10:45 AM

I designed mine the way it is in order to be able to accommodate the handwheel wheel hub which couples to the outer surface of the pinion gear, rather than via the axle, because the axles have been known to snap, I wanted to have it freewheeling not transmitting torque and i wanted the bearing surface to be the outer surface of the hub. (edited)

10:47 AM

That way no need for a ballrace bearing

10:48 AM

and the bearing surface has a large radius so the force is distributed better than on a small axle

Timberstar started a thread. 5/26/2022 11:18 AM

sonik

They use loudspeaker-connections for 220V mains??? As we can read on the website of the manufacturer NEUTRIK : "speakON is not to be used as an AC mains or power supply connector!" They should at least use powercon connectors. (edited)

yes this is not safe and shouldn't be on the bazaar really

Lots of good ideas and suggestions. The discussions are already going about details though. I would suggest to zoom out first, define the functional specifications of the machine (Weight / max power input / pressures / temperatures / shot volume / clamping force etc.) and define the type of tools you want to use to build it. Not sure if you have done that already, could be that I missed it

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Thank you for this picture, this help a lot. I added some number so it is easier to ask questions, I named your blocks A, B, C & D, and holes 1, 2, 3, 4 & 5 I am personally very "no mill" oriented, so excuse in advance my questions, I know they tend to piss machining guys ! (That doesn't mean we need to design without a mill, I am just challenging it) Question 1 : you need to have these A 1, 2, 3 & 4 very precisely aligned with D 1, 2, 3 & 4 because you need to have the axis holes A 5 and D 5 perfectly aligned ? If you allow some tolerance in the 1, 2, 3 & 4 holes, wouldn't the 5s self align ? Laser cut tolerances are generally not that bad for relative position between holes. Question 2 : my understanding on C 5 hole is that it doesn't need to be very precise, just go around the gear, but it doesn't need to guide it or anything ? Question 3 : A 5 and D 5 need a precise diameter to allow a proper rotation of the axis. Still in a idea on laser cutting everything, what would be your opinion on a copper (or copper + graphite) insert as a diameter rectification ?

With precision holes I sometimes use lasercutting, with the hole 0,2 mm undersize, followed by reaming the hole to the required diameter. Reamers are available in a wide range of sizes and tolerances.

1

Yann

Thank you for this picture, this help a lot. I added some number so it is easier to ask questions, I named your blocks A, B, C & D, and holes 1, 2, 3, 4 & 5 I am personally very "no mill" oriented, so excuse in advance my questions, I know they tend to piss machining guys ! (That doesn't mean we need to design without a mill, I am just challenging it) Question 1 : you need to have these A 1, 2, 3 & 4 very precisely aligned with D 1, 2, 3 & 4 because you need to have the axis holes A 5 and D 5 perfectly aligned ? If you allow some tolerance in the 1, 2, 3 & 4 holes, wouldn't the 5s self align ? Laser cut tolerances are generally not that bad for relative position between holes. Question 2 : my understanding on C 5 hole is that it doesn't need to be very precise, just go around the gear, but it doesn't need to guide it or anything ? Question 3 : A 5 and D 5 need a precise diameter to allow a proper rotation of the axis. Still in a idea on laser cutting everything, what would be your opinion on a copper (or copper + graphite) insert as a diameter rectification ?

1) Yes. You don't want any slop in the holes because the alignment of the rack needs to be quite accurate. That's why I used brass bolt sleeves in the pic, but plain dowels would be better, with threaded ends for nuts, or stud bolts with full diameter shanks to full length of the hole, but those would be hard to find. The blocks need to be very accurately aligned and tightly bolted because the housing is bearing all the forces in every direction. It would be ok if the bolt holes were not quite in the right place, as long as you drilled through all the pieces at the same time so they will align. But then you would have to put the gearbox back together exactly the same way each time without flipping any parts over.

12:40 PM

2) C5 needs to be aligned nicely because the side of the spur gear bears against it, but it doesn't need to be a nice finish or extremely accurate diameter.

12:43 PM

3) i thought about some kind of bushing, yes, but at that diameter they are expensive and i would have needed to make the overall dimensions of the gearbox larger to accommodate it. Laser cutting is not feasible at 30mm thickness anyway, this is a job for the mill, really. Even quite a basic mill should be able to do this in a few hours, it's only aluminium.

12:49 PM

the handwheel hub, however, needs to be steel and needs to be done on a lathe. I can't see any way round that using some kind of clever laser cutting and i think its a waste of time to try.

Peter-Bas

Lots of good ideas and suggestions. The discussions are already going about details though. I would suggest to zoom out first, define the functional specifications of the machine (Weight / max power input / pressures / temperatures / shot volume / clamping force etc.) and define the type of tools you want to use to build it. Not sure if you have done that already, could be that I missed it

The main specification I've been working with is an input force of 300N, which is roughly half the average bodyweight of a person, I think we agreed on this on the video call? Anyway it seems reasonable that a person can exert that force downwards on the handwheel bar. Many of the other parameters are determined by availability of components and materials. The parameter for the injection volume is determined by the internal diameter of the barrel x length of stroke. The internal diameter of the barrel of 25.7mm was chosen because heavy guage 1" BSP pipe has an outer diameter which conveniently accommodates the common 35mm heat bands. The stroke length is determined by the length of rack, which is available in 500mm or 1m lengths, so 500mm minus 100mm for the gearbox= 400mm; so the overall chamber volume is roughly 62.5cm2.

1:12 PM

While specs are useful I find it better to design from first principles, eg maximizing pressure means maximizing torque by using the longest handwheel bars possible, using the smallest spur gear possible, using the 25 rather than 30mm barrel etc (edited)

I think more important than specifications is the actual brief, as in what is this machine for. To my mind, since this is a hand-operated machine, we should not aim to maximize injection volume but concentrate instead on achieving as good cavity pressure as possible for small, detailed objects.

1:23 PM

this means the smaller spur gear is ok, since we don't need to fill a large mould rapidly, we can opt for higher torque and therefore pressure, rather than injection speed

1:26 PM

To be honest, the biggest challenge with this machine is not the gearbox but the handwheel. It needs to be very big - 1.8m for best pressure! But I don't like the idea of 900mm metal bars swinging around near my head, so it needs some kind of outer rim. Making that nicely will be difficult. (edited)

1:31 PM

@Yann Another reason to do it on the mill, if you use my design, is that the back block B could be flipped over once it gets worn if all the holes are perfectly aligned.

Timberstar

I think more important than specifications is the actual brief, as in what is this machine for. To my mind, since this is a hand-operated machine, we should not aim to maximize injection volume but concentrate instead on achieving as good cavity pressure as possible for small, detailed objects.

Well these kind of things are exacly part of the functional specifications. I guess it's up to @Joostie to find a structure in this. Big challenge. I missed the video call a while back, so might be missing some background info

Peter-Bas

Well these kind of things are exacly part of the functional specifications. I guess it's up to @Joostie to find a structure in this. Big challenge. I missed the video call a while back, so might be missing some background info

To my mind, the brief will include things like 'hand operated, maximize this, minimize that' while the specifications which are derived from the brief will be specific parameters like 50-100cm2 volume or 300N input. You are right though, a clear brief produces realistic specifications, and its worth spending a lot of time on the brief before starting to draw. For me though, the specifications can be retrospectively determined by design elements, but the brief itself cannot. (edited)

Agreed, I think we should discuss the exact brief. Based on the interviews I did with all kinds of machine builders, my vision for the machine is based on the following: 1) There is a wide range of builders/users: On one hand, there are people with little engineering knowledge that mainly aim to 'casually' recycle. They use it for workshops or somewhat low-volume production. This means they are not looking for a beefed-up, highly engineered machine and actually look for something that is relatively easy to build (similar to the lever press). 2) On the other hand, there are builders with quite a bit of engineering knowledge that do have the capacity, skill, or budget to use somewhat advanced machining methods like milling/lathing. 3) It's not a good design goal to create one machine that will suit both builders: this will leave either or both unhappy. Based on this, my design vision is as follows: We should aim for a machine that is buildable for the first target group, designed in such a way that certain modules can be upgraded if you have access to a mill/lathe. Within the final design package, these will be added for builders to see and choose if they have the skill/budget. The reason I'm choosing the 'workshoppers' as my primary target group for this project is that these builders won't have the engineering knowledge to 'simplify' milled parts into e.g. a laser-cutting solution, so a well-designed machine for them would add more value. The engineering knowledge present in this channel is the living proof that milled upgrades will eventually pop up as 'how-to's for those looking for it, so won't have to be the primary focus of this project. (edited)

2

4:20 PM

To be more specific, this means the following for the choice on type of tools:

As little milling/lathing as possible. Probably there will be some small parts for which this is unavoidable (like the axis with keyway), but eventually these could be sold on the Bazar making them still accessible for the 'workshopper' target group. This means we mainly need an alternative for the milled gearbox (like in the mrpete video), which is what I've been working on. My previous idea had quite some flaws though, so I made a revision (see below).

I was a bit hesitant on laser cutting as well as it's also quite expensive/hard to access for some, but I'm starting to see that not using both laser cutting and milling results in quite some engineering challenges. Therefore I'm considering it.

4:21 PM

Taking the above into account, I made a new version of the basic rack/gear system. You can find it on the Partnerspace as Assembly 2 (https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC/folder/12021184). Some differences/new features are:

I ditched the 'no welding' goal as this would indeed make it overly complicated. The frame parts and casing include welding joints.

The gear suspension is now enclosed in a laser-cutted casing. The back of the casing can be welded to the frame. The front is attached to the frame by bolts so 1) it can be slightly adjusted to align its position to the axis holes on the back casing and 2) it is removable for maintenance/gear change. Not sure if this is the perfect solution, curious what people think. Would need prototyping and testing to see how feasible it is to align the axis holes in this way.

Opposite the spur gear, the rack is supported by two sling bearings on shafts. They are held in place in slots within the casing, which means that 1) you can position the rack for a good engagement with the spur gear, and 2) you can change the spur gear to a larger one if necessary without needing to make a new rack suspension (see image). Making the borehole in this part is probably tricky without a lathe, I'm not sure it's doable with a standing drill. I'm looking into other solutions here, let me know your ideas.

To suspend the rack in the lateral direction, I added Teflon strips to prevent metal wear as suggested.

The main axis now features a keyway to engage the spur gear, which should also prevent wear.

GrabCAD

The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

4:21 PM

Let me know your thoughts! Again for clarity: I'm posting all baby steps in developing the machine to get input along the way, but right now this means there's a lot that is still missing. Frame rigidity, barrel suspension, etc are upcoming topics: For now I'm mainly looking for input on the gears and their suspension. On a final note: I think we should be aware that the engineering expertise in this channel is a lot higher than with most machine builders. It's a great resource, but we should use it to design a machine that can be built by people with half our knowledge.

4:23 PM

Wehw, loads of text

TLDR: Aim is to build a machine for people with little engineering knowledge, with room for CnC-able upgrades. New version of gearbox system is there, and keep the ideas coming!

1

Lekker bezig!

1

Joostie

Taking the above into account, I made a new version of the basic rack/gear system. You can find it on the Partnerspace as Assembly 2 (https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC/folder/12021184). Some differences/new features are:

I ditched the 'no welding' goal as this would indeed make it overly complicated. The frame parts and casing include welding joints.

The gear suspension is now enclosed in a laser-cutted casing. The back of the casing can be welded to the frame. The front is attached to the frame by bolts so 1) it can be slightly adjusted to align its position to the axis holes on the back casing and 2) it is removable for maintenance/gear change. Not sure if this is the perfect solution, curious what people think. Would need prototyping and testing to see how feasible it is to align the axis holes in this way.

Opposite the spur gear, the rack is supported by two sling bearings on shafts. They are held in place in slots within the casing, which means that 1) you can position the rack for a good engagement with the spur gear, and 2) you can change the spur gear to a larger one if necessary without needing to make a new rack suspension (see image). Making the borehole in this part is probably tricky without a lathe, I'm not sure it's doable with a standing drill. I'm looking into other solutions here, let me know your ideas.

To suspend the rack in the lateral direction, I added Teflon strips to prevent metal wear as suggested.

The main axis now features a keyway to engage the spur gear, which should also prevent wear.

Forgot the image:

1

Yann started a thread. 5/26/2022 4:44 PM

Joostie

Forgot the image:

I tried a few ways attempting to accommodate different gear ratios and decided it's really not worth the effort. The difference between the two sizes doesn't really make a huge difference to the pressure, and the additional complexity of the gearbox is a nightmare. The rack can't move horizontally as you've drawn it, because everything below it must align (plunger, barrel etc), so it has to be the pinion gear which moves, and to do that you're really compromising the strength at the critical point of force transfer. It's just adding problems for little gain. I suggest the 16 tooth gear as it's significantly cheaper than 22 or 30, and will give the highest possible torque for a Mod 3 rack (they don't go smaller than 16T at that gauge). Smaller gear also means smaller overall dimensions for the gearbox, so less material making it cheaper too. There's no need for rollers behind the rack, it will slide perfectly fine against a flat face.

1

correction: Spur gears at Mod 3 are also available with as few as 12 teeth https://www.gearsandsprockets.co.uk/metric-mod-3-steel-spur-gears/

Metric MOD 3 Steel Spur Gears

10:49 PM

also it seems i was wrong about the difference in price, it's not that much

It's a while since I drew this so my memory is a bit vague but it looks like I increased the bore on the gear from 15 to 20mm to allow a shoulder on the axle. This is necessary to be able to tighten the nuts without squeezing against the gearbox and stopping the movement. Also 20mm diameter axle can take a lot more force than 15mm

11:18 PM

I think that's why i went for 16teeth, because anything smaller than that can't take a 20mm axle

I have been informed that even 20mm is prone to bending and that 25mm would be more appropriate. That would mean even the 16T would be too small. I'm not sure, I think it would be worth trying at 20

Y'all have done so much work on this already. My dream is that this could be made from something you can find in the junk yard. like the worm gear in a scissor lift, or the Ratchet gear on a farm jack somehow used in reverse? Many 2 or 3 options for this press would be great! but I know we have to start somewhere and rack/pinion is as good a place as any I guess.

2

Hello @Contributor ! was a super nice meeting this morning, with a lot of good feedback! I've seen lots of models and drawings shared here and i would like to let you know that if you would like to, you can upload your 3D models to our grabcad workbench (can be parts, assemblies or whatever you have that you think is useful), so that we can take a closer look and discuss about it

If you are interested give me your grabcad account email to invite you as collaborator

(edited)

5

Something it came back to my mind about the plunger is resting within the barrel - I think you really want to avoid that due to the thermal transfer of the barrel into the plunger. If the plunger heats up, there will always material stick to it which is really annoying. Ideally the plunger rests out of the barrel and can cool and pushes always on cold material -> no sticking of plastic to it. Also a good reason for three heat zones, but that gets a bit too far I think ;D (edited)

3

So lovely to meet you guys - and quite the exciting project! Thanks for letting me join in on the meeting. @Carolina I'd love to be added to grabcad - I'll PM you my email. I drew up my idea for the laser cut modular rack and pinion, if there are other laser cut parts in this build, it might be easy to keep it all LC. I'd suggest them being cut from different thickness steel ( for example rack is 3mm and pinion gear 5mm in these screenshots) all 8 rack pieces, and 5x gear pieces would cost about $20usd TOTAL from my supplier - far cheaper than a rack!

@Taylor nice! i'll be waiting for you username to invite you to the grabcad! I have some questions regarding the laser cut rack. Dont you think it can get tricky to make sure all the teeth are clean without having to debur each one of them? (edited)

And finally - here's an idea for the "hub" or handle mech, using the laser cut gear mentioned above. This one would require no machining and probably cost another $20 in laser cutting... - it would need 20mm SHS welded on for handles

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Carolina

@Taylor nice! i'll be waiting for you username to invite you to the grabcad! I have some questions regarding the laser cut rack. Dont you think it can get tricky to make sure all the teeth are clean without having to debur each one of them? (edited)

Great thinking! There'd likely be a bit of post processing, however I've just used a wire wheel to clean them up in the past and had no issues - they wont be the cleanest teeth, but the commercially available racks and sprockets are meant for high load, high precision applications - and this machine is neither of those!

heh nice work! I would love to see if that would actually work.

4:48 PM

@Carolinacould you post a link please for the Grabcad workspace? the one I used before doesn't work

you mean the partnerspace to see joost's model? or the one for you to upload your files?

to upload

obviously less load

but these were just cleaned up with a wire wheel, and otherwise straight from the laser cutter - depends how dependant we want people to be on their local laser cutting shop, or whether spending a bit more and ordering a precision part from their local precision part supplier is simpler all around

Really cool stuff @Taylor ! I'll try compare it on cost and effort to the stock rack to see which is the best option for the 'official' version or whether it would be an upgrade/alternative. Anyway, cool stuff!

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Carolina

Hello @Contributor ! was a super nice meeting this morning, with a lot of good feedback! I've seen lots of models and drawings shared here and i would like to let you know that if you would like to, you can upload your 3D models to our grabcad workbench (can be parts, assemblies or whatever you have that you think is useful), so that we can take a closer look and discuss about it

If you are interested give me your grabcad account email to invite you as collaborator

(edited)

What meeting? What did I miss?

Thomas Peterberns | Johannplasto

What meeting? What did I miss?

It was on the events here on discord! we did a feedback session about the first 3D model from Joost

@Thomas Peterberns | Johannplasto there is an option to add events to your calendars so you don't miss them in the future

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I know @Peter-Bas suggested UHMW as a good bearing material for the arbor press - and if there’s concern on availability getting the right bearing blocks in, I’ve used chopping boards as a cheap source of UHMW plastic, might help improve sourceability around the world if there’s a suggestion to use chopping boards

Example ➡️ https://www.ikea.com/au/en/p/legitim-chopping-board-white-30202266/

LEGITIM Chopping board, white

LEGITIM Chopping board, white.

2

Hello everyone! So after the last feedback round, @Joostie put the feedback together in a very nice diagram that shows the different assemblies of the machine and all the options and ways of building the same with different techniques / manufacturing methods. We are still working on which one we will choose from each section (for the first prototype) but i invite you all to take a look at this Loom video to undestand better what im talking about

https://www.loom.com/share/70397b5af9ad48ddb9e8a4ce0778e9ea and then jump into this miro board

https://miro.com/welcomeonboard/TDdzQ0FqRUdka3hQSEpHdktjOW5xcDBiejVOVGR0aDBnTjc0dm5DN1Voc2t6dGRtTkFFbHpYaFBpdkdrSVdwT3wzNDU4NzY0NTI2OTg4MzE1NjM3?share_link_id=878038696431 to have a closer look to the diagram and add some more ways of bulding the same part (if you feel there’s any missing), we already added our comments

. We feel this kind of tools will allow us and the community have a better overview of the different ways of building the same machine and at the same time will make it easier for others to contribute with designing and prototyping a specific part or assembly of a machine. What do you think?

(edited)

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3

5:29 PM

Hello. Since I'm planning-reflecting on how to inject my encolusures, I just thought, did u ever think about making an injection machine with 3 heated barrels, instead of 1 only, that would let people inject 3 times the capacity of 1 barrel machine per time? It would cut by 2/3 injection times and will let you fill larger molds. Have a great day. (Do not know if this is the right place to post this) (edited)

Carolina

Hello everyone! So after the last feedback round, @Joostie put the feedback together in a very nice diagram that shows the different assemblies of the machine and all the options and ways of building the same with different techniques / manufacturing methods. We are still working on which one we will choose from each section (for the first prototype) but i invite you all to take a look at this Loom video to undestand better what im talking about

https://www.loom.com/share/70397b5af9ad48ddb9e8a4ce0778e9ea and then jump into this miro board

https://miro.com/welcomeonboard/TDdzQ0FqRUdka3hQSEpHdktjOW5xcDBiejVOVGR0aDBnTjc0dm5DN1Voc2t6dGRtTkFFbHpYaFBpdkdrSVdwT3wzNDU4NzY0NTI2OTg4MzE1NjM3?share_link_id=878038696431 to have a closer look to the diagram and add some more ways of bulding the same part (if you feel there’s any missing), we already added our comments

. We feel this kind of tools will allow us and the community have a better overview of the different ways of building the same machine and at the same time will make it easier for others to contribute with designing and prototyping a specific part or assembly of a machine. What do you think?

(edited)

@Joostie your illustration skills on this miro board.....wow. Such a nice chart!!!

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101 E.

Click to see attachment 🖼️

Great thinking - I'm currently finishing off an injection machine with two barrels - and hoping it works as well as we both think it should! I'll be posting results shortly when I begin testing

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Taylor

Great thinking - I'm currently finishing off an injection machine with two barrels - and hoping it works as well as we both think it should! I'll be posting results shortly when I begin testing

I'm in need to inject 0.8kg circa per injection so one barrel only could not. ✨✨ Tag me, curious to look at the final result

101 E.

I'm in need to inject 0.8kg circa per injection so one barrel only could not. ✨✨ Tag me, curious to look at the final result

I'm hoping for 350gm approx on this unit, but it's modular with the ability for two or more of these to join together (for 4 or 6 or 8 barrels) to make a 700gm, 1.05kg, or 1.4kg shot - so it's definitely doable!

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Taylor

I'm hoping for 350gm approx on this unit, but it's modular with the ability for two or more of these to join together (for 4 or 6 or 8 barrels) to make a 700gm, 1.05kg, or 1.4kg shot - so it's definitely doable!

Interesting, man. Keep me updated. Thumbs up for modularity.

@Joostie just had a sec to look at your loom, so neat! Love your thought process ♡ can't wait to see the machine coming to life!

Note for the Handwheel. This has to be stronger. This ist after using about one year.

Imagine now doing that with Lasercut parts ;D The diameter of the wheelhub has to be larger and you need a pretty good tolerance fit that it works like that. Would rather add threads all around and fix them with Loctite afterwards.#

Fritz @easymoulds

Imagine now doing that with Lasercut parts ;D The diameter of the wheelhub has to be larger and you need a pretty good tolerance fit that it works like that. Would rather add threads all around and fix them with Loctite afterwards.#

Yes, this has to be designed very strong.

Thomas Peterberns | Johannplasto

Note for the Handwheel. This has to be stronger. This ist after using about one year.

You may be able to find them as standard parts at Norelem/ Ganter/ Kipp etc. - not sure about the dimensions etc. but might be an easier fix for you?

Thomas Peterberns | Johannplasto

Note for the Handwheel. This has to be stronger. This ist after using about one year.

are these levers screwed into the handwheel? or they are attached with the bolt?

Carolina

are these levers screwed into the handwheel? or they are attached with the bolt?

Attached with the bolts. The levers screwed would be risky. If it’s too weak it’s difficult to repair.

Thomas Peterberns | Johannplasto

Note for the Handwheel. This has to be stronger. This ist after using about one year.

Needs more mig welding!

(edited)

If we need strength, durability and third world simplicity - how about a laser cut modular wheel / hub assembly? Each section is small enough to be cheap to laser cut, and there's no joins or welding required (although a bit of optional welding would be nice to make it stronger)

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Works, but ergonomically questionable as everyone knows that tried to get the speced 72bar out of a Plasticpreneur machine. You cannot apply the full force to the circumference of the wheel, neither to its diagonals. Would work if you extend the diagonals beyond the wheel and add nice round handles to them.

2

8:43 AM

Might be a bit questionable in material use / environment concious design still...

Thomas Peterberns | Johannplasto

Note for the Handwheel. This has to be stronger. This ist after using about one year.

Is the hub aluminium or steel?

Rory - Sustainable Design Studio

Is the hub aluminium or steel?

Steel.

Fritz @easymoulds

Imagine now doing that with Lasercut parts ;D The diameter of the wheelhub has to be larger and you need a pretty good tolerance fit that it works like that. Would rather add threads all around and fix them with Loctite afterwards.#

im wondering something, would a laser cut option be enough for prototyping? because the problem seems to be the long term durability

Thomas Peterberns | Johannplasto

Steel.

Man, that's such a huge chunk of heavy and increasingly expensive material. Shame to see it fail like that but as they say, a chain is only as strong as its weakest link. Clearly the narrow connection just doesn't have enough strength when compared with the large hub just being overkill in the end. I bet that hub weighs a tonne too and makes shipping harder and increases the need for a bigger base due to the weight on one side of the machine.

Thats about the best design you can find out there - just cleverly engineer your way backwards to make it more simple and good to last for 10 years

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Carolina

im wondering something, would a laser cut option be enough for prototyping? because the problem seems to be the long term durability

Yes you can, but why? I am sure the university there has everything to make these parts. Namingly you need a drill press, drills one/two reamers and a tap if you want to have threads inside. If you want fancy geometries/ergonomics a lathe helps too

Fritz @easymoulds

Yes you can, but why? I am sure the university there has everything to make these parts. Namingly you need a drill press, drills one/two reamers and a tap if you want to have threads inside. If you want fancy geometries/ergonomics a lathe helps too

was more about saving some prototyping costs and time, considering that there are quite a few things being tested at the same time.

Fritz @easymoulds

Works, but ergonomically questionable as everyone knows that tried to get the speced 72bar out of a Plasticpreneur machine. You cannot apply the full force to the circumference of the wheel, neither to its diagonals. Would work if you extend the diagonals beyond the wheel and add nice round handles to them.

Understood! In that case perhaps we extend the diagonals beyond the wheel? The only reason I’m such an advocate of laser is that there are already laser cut parts required for the build, so it doesn’t add anything. If a local joe has to source a welder, laser cutter AND a machine shop to make a machine - that’s full on. And depending where you are in the world, a machinist is likely the hardest to source. I don’t care if it’s not laser cut - however I think a machined part where it’s quite unnecessary is, well, unnecessary. I have the rare privilege of owning my own (self built) cnc mill and cnc lathe. However I only was able to build them because I could build the parts without using cnc mills and lathes. If the laser cutting is already a must, I don’t like the idea of adding another supplier/ trade / cost just to make one (expensive) part, that could be made via another method. I mean shit - why don’t we have them attach a bicycle wheel or the top of a steel 55 gallon drum? I believe the basic instructions should be as basic as possible - and let the builder improve where they have the means. Ultimately - I believe we should be providing instructions for the minimum viable product, not the optimised production quality mass productions model. And also, having the end users send out a STP file to machine shops for quotes only really works in the western world

/soapbox, thanks for sticking with me

- I’m happy to hear counter points!

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Good old Landry made a slick arbor design, maybe some food for thought @Joostie https://www.instagram.com/p/CenmW8Nt4Nt/?utm_source=ig_web_copy_link

lerecycleurfou

MILLENIUM, injecteuse à crémaillère, notre deuxième recycleuse de plastique après la DESTROYER. Fiable, solide, rapide et puissante, elle facilitera le travail de l'injection plastique. On est très fier de vous présenter ce modèle sur lequel on travail depuis près d'un an. Composée d'un ensemble pignon/crémaillère pour développer une puissante ...

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Mattia

Good old Landry made a slick arbor design, maybe some food for thought @Joostie https://www.instagram.com/p/CenmW8Nt4Nt/?utm_source=ig_web_copy_link

He’s not super active on discord but super open to answer any questions regarding his machine! I already did

*his gearbox , handwheel and rack are aluminum CNC

Love the mould stand feature

Mattia

Good old Landry made a slick arbor design, maybe some food for thought @Joostie https://www.instagram.com/p/CenmW8Nt4Nt/?utm_source=ig_web_copy_link

Looks great! I hope the springs for the mould table are not too weak. With high injection forces (F=pxA), the force can push the springs and you get a splash out. I designed a mould for the plasticpreneur machine and we had big problems with the spring loaded table, because the springs were pushed before the mould was full and we got a splash out at the nozzle. I also like to see this machine in action. I hope it wobbles less than the plasticpreneur machine.

Hey everyone, I took a short break last two weeks, hence the lack of response from my side

11:03 AM

I haven't responded to all topics but I've read everything, thx for your thoughts and feedback

11:05 AM

I'll probably work on the handlewheel this week, so expect some tryouts and ideas coming your way

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can't wait

hello guys, you might find the INJEKTO 2.0 diy pneumatic injection molding machine interesting

1:53 PM

https://www.youtube.com/watch?v=M28Pbrm7wzE

Action BOX

Homemade Plastic Injection Machine Works With 3D Printed Molds | IN...

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@enkiI did a (better) version of their injekto 1.0 and i am really happy with it. Very easy to built.

sonik

@enkiI did a (better) version of their injekto 1.0 and i am really happy with it. Very easy to built.

Do you have some pictures / videos to share?

would be very interesting to see

4:28 PM

4:29 PM

I left everything outside the heat chamber. the tube is held by two satelite-dish-clamps

4:30 PM

4:31 PM

the "heating chamber" slides with F608 Flange bearings on the pneumatic cylinder ( about 2cm, just enough to get the mold under).

4:32 PM

the back

4:33 PM

Hi Tech Plumming Nozzle wuth some heat protection

4:34 PM

Hi Tech refilling device

4:36 PM

Start with low pressure rates and not with ten bars like me

or you'll end up exploding your mold (edited)

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sonik

Click to see attachment 🖼️

awesome

sonik

Click to see attachment 🖼️

excellent work !!

sonik

Click to see attachment 🖼️

we need an how to for this one too

sonik

Click to see attachment 🖼️

there is a support team for creating how tos? i am seeing lots of wonders that people struggle to share because of little time for doing that. Maybe we can start partial how tos or collaborative ones in the style of forums but much more topic centered than a thread (like PP how to style is IMO). just thinking out loud

Taylor

I'm hoping for 350gm approx on this unit, but it's modular with the ability for two or more of these to join together (for 4 or 6 or 8 barrels) to make a 700gm, 1.05kg, or 1.4kg shot - so it's definitely doable!

Hello, man, any update about the multi-barrel build?

Hey everyone! It's taken some time, but the latest Arbor press development model is online

Check it out on the GrabCad partnerspace (https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC). To make design choices a little more clear, I've made a document which explains a lot of stuff. Check it out below and please do let me know about all your ideas/improvements/suggestions! Cheers! (edited)

Arbor_Press_review_4_-_Development_Notes_-_MUST_READ.pdf

618.7 KB

GrabCAD

The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

Here are some pic's and a video of the first prototype

https://photos.app.goo.gl/TkKG52igH2vGYewe9 (edited)

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2

1

4

To clarify the overall idea behind this model, its good to know about some choices we made in the last week. Some time ago, @carolina , @Yann and I decided to split up the development of the machine in two types (their names will probably change soon

):

The advanced type, which will be the main version and will be made from machined parts (the current latest model on GrabCad). As the overall design idea of the Arbor Press is that it's a better version than the lever injection, it makes sense to use milled/lathe parts as they allow for a better, more durable design.

The basic type, which is fully made with lasercuttable and storebought parts. As I'm not sure how durable this would be, this is the 'B' version for now. Still, I'm trying to see if it's possible as I think it would be a much more accessible version for people without access to a lathe and mill.

For an overview of the differences between these two, check out the attached pdf below. The pictures of prototype I shared are based on the basic type. This prototype seems to work pretty well and will be tested more over time. Over the last weeks I've also been working on the advanced type, which is the model that is now also on the partnerspace. For now, please send me all your thoughts and comments for the advanced type, cause I'll be making a prototype for that in the coming weeks

(edited)

Arbor_Press_review_4_-_Design_Philosophy.pdf

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Joostie

Here are some pic's and a video of the first prototype

https://photos.app.goo.gl/TkKG52igH2vGYewe9 (edited)

That's just begging for a ships wheel!

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Btw, do people have experience with using barrel tubes with a larger inner diameter? I can't really find the 1" BSP tubes in NL for a reasonable price

2:17 PM

I've found something with 29mm inner diameter, anyone with experience if that'll work here?

Did you check for hydraulic tubes to make custom cylinders?

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4:50 PM

Ohh and if you go for them take care there is enough safety margin for the injection pressure!

4:51 PM

e.g. https://www.landefeld.de/artikel/de/praezisions-hydraulikrohrnahtlos-30x50mm-schwarz-phosphatiert/HR%2030X5

Okay this is becoming a bit of a longer one - went through the machine design step by step, might miss still some points but maybe the others can complete. Do it as single posts, so its easier to comment/feedback on The good points first: + Very cool design of the adjustable gearbox bearing plate!! + Super nice implementation of the laser cut stress-relief cap plate! // Piston head from brass works well

1:15 PM

Strong suggestions

1:15 PM

Why Squared tubes for the handles? Will reduce the applicable force unnecessary by ergonomics and will cause pain in using the machine over a longer period of time (production times of 1-3 days are quite common) - is in no relation to the saved money/ saved inventory cost. Round bars are accessible as Squared ones - either solid or tubes.

1:15 PM

Remove the chamfer on the piston rod and add it on the barrel (15-30° with a rounded lower edge) -> will Jam the material between plunger and barrel wall

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1:15 PM

Did you simulate the stress on the frame where the height positioning holes for the mould are located? (I ditched this concept on my own machine for this reason, but ~3x more force - so may work here)

1:15 PM

No bearings for the axis of the advanced version? - if so, what is the material combination for the axis and for the gearbox case?

1:15 PM

Suggestions

1:15 PM

Reduce the number of milled parts of the gearbox to two, level the bolts with countersinks

1:16 PM

~~- Maybe the handle wheel core could be subsidized by two/ a stack of lasercut plates that are connected by pins + bolts?~~ - just seen that you have done that on one version (edited)

1:16 PM

Check the Handle diameter and compare it to the standard of ergonomics or standard parts (so everyone can grip it well)

1:16 PM

My gut feeling says the cap plates may use 5/6mm instead of 3mm thickness - same for the Lasercut Gearbox plates of the basic version

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1:16 PM

The spring loaded mechanism for the nozzle engagement looks overcomplicated - why not guide the barrel directly in two thick Steel/Brass plates?

1:16 PM

Not sure why you don't use a normal spring for 5€ and make a custom part instead?

1:16 PM

Test recommendations

1:16 PM

Measure time to drive the full travel of the wheel with different people, maybe add a spring to simulate forces?

1:16 PM

Check the force that is generated by the plunger with a high load weight cell (should be available at some departments) with various people to see limits there

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From the ergonomics book, the values seem a bit on the lower end, so probably fine to add 20-30%

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Thanks a big lot @Fritz @easymoulds!! I just skimmed over your points, I'll reply where necessary tomorrow

Fritz @easymoulds

Why Squared tubes for the handles? Will reduce the applicable force unnecessary by ergonomics and will cause pain in using the machine over a longer period of time (production times of 1-3 days are quite common) - is in no relation to the saved money/ saved inventory cost. Round bars are accessible as Squared ones - either solid or tubes.

Good point, I used square tubes as they are already used in the build, but they are indeed not great ergonomically.

Fritz @easymoulds

Did you simulate the stress on the frame where the height positioning holes for the mould are located? (I ditched this concept on my own machine for this reason, but ~3x more force - so may work here)

I did some simulations to check this and there should be no problem even at extreme loads (max stresses are less than 30% yield strength with full-body input force). However, this might change with wear over time, so I'm curious what your solution is

Fritz @easymoulds

No bearings for the axis of the advanced version? - if so, what is the material combination for the axis and for the gearbox case?

Indeed no bearing, the material combination is steel (axis) and aluminum (gearbox). Should work fine according to prior experiences from others in this channel, I'll see in testing if some kind of plain bearing is needed. If so, this should be quite easy to integrate.

Fritz @easymoulds

Reduce the number of milled parts of the gearbox to two, level the bolts with countersinks

I opted for the 3x 100x30x165 blocks, as 100x30 extrusions are much easier to get in NL than larger blocks (in my experience). I made the assumption this is the case in other places as well, but this might not be true. Having fewer parts to align would indeed make for less fuckups, so I'm not sure what's best here.. Might be good to get some input on aluminium accessibility.

Fritz @easymoulds

The spring loaded mechanism for the nozzle engagement looks overcomplicated - why not guide the barrel directly in two thick Steel/Brass plates?

I agree this might be a bit overcomplicated now.. My reasoning is that the barrel should have some kind of end stops to prevent overstretching/compressing the spring. This is mainly what the bolts+bushings are there for. The barrel could also serve this function, but then you would need some kind of metal rings on there (red on image). Maybe a clamping ring could do this, but that might be hard to find in this diameter. Could be something to be homemade on a lathe, or else something with a set screw.. Not sure what the best solution would be, anything besides welding would be an option. I'll check out other solutions and share them here

Fritz @easymoulds

Not sure why you don't use a normal spring for 5€ and make a custom part instead?

I think the plate spring would make sense for places where regular springs would be more of a hassle to find, however I think a regular spring could indeed be the better option for the advanced build as it makes more sense.

1:12 PM

Thanks a lot again Fritz, great stuff! ❤️ ✨ (edited)

Joostie

I agree this might be a bit overcomplicated now.. My reasoning is that the barrel should have some kind of end stops to prevent overstretching/compressing the spring. This is mainly what the bolts+bushings are there for. The barrel could also serve this function, but then you would need some kind of metal rings on there (red on image). Maybe a clamping ring could do this, but that might be hard to find in this diameter. Could be something to be homemade on a lathe, or else something with a set screw.. Not sure what the best solution would be, anything besides welding would be an option. I'll check out other solutions and share them here

Forgot the image

Carolina started a thread. 7/13/2022 11:50 AM

Joostie

Hey everyone! It's taken some time, but the latest Arbor press development model is online

Check it out on the GrabCad partnerspace (https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC). To make design choices a little more clear, I've made a document which explains a lot of stuff. Check it out below and please do let me know about all your ideas/improvements/suggestions! Cheers! (edited)

would be cool to have these notes in an open google docs to add comments to it

Carolina started a thread. 7/13/2022 12:20 PM

btw @Joostie and everyone! lets try to use "Threads"

!

just want to say hi and how i am amazed by the work that is going on here.

. I am learning something from the (partial) exposure of the design process (and implementing something in the build of my regular injection machine), i can't wait for the next steps of the project

, keep up the great work and thanks for sharing/building things together

️

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Hey everyone, I just uploaded the latest model of the advanced arbor press, check it out on the partnerspace! https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC/folder/12021184 I'm almost done with the prototype and will be doing the first shots next week

(edited)

GrabCAD

The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

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1:37 PM

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Nice one @Joostie congrats on the first prototype!

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Prototype is looking good and very soon will be ready to be tested

We still have some things we are wondering whats the best approach, like: 1) Length and quantity of levers (to make sure is functional but still ergonomic). For the moment we just divided a full beam in 5 equal parts. 2) Height adjusting system for the mould bed: has to be simple and easy to adjust, no need to be super precise. Just for the record, we don’t want to use any sort of car jack, since this can cause that operators put too much pressure upwards and the frame is not built for that (and basically defeats the purpose of using the spring loaded system). 3) Barrel cover: we need to make sure there’s enough space for the cables an insolation material and make it easy to disassemble for maintenance. I think we will have a better idea of whats the best option once we try the first prototype, but we would love to hear your opinions or suggestions based on your experience ✨

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Some Ideas: 1.) Just applied Testing of Speed vs. Pressure vs. various Users

Maybe manufacture multiple wheels and compare them against each other 2. Welding multiple of these beams as they already there ? (see image attached). Like every 100mm or so, have a flat bed resting on them. Use spacer blocks to adjust the rest of it. 3.) Yes ;D (edited)

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Fritz @easymoulds

Some Ideas: 1.) Just applied Testing of Speed vs. Pressure vs. various Users

Maybe manufacture multiple wheels and compare them against each other 2. Welding multiple of these beams as they already there ? (see image attached). Like every 100mm or so, have a flat bed resting on them. Use spacer blocks to adjust the rest of it. 3.) Yes ;D (edited)

Hey! thanks for this

1)Yes, i think that's the best aproach. Will definitely do it during the testing phase. 2) not sure i got very well how its supposed to be adjusted up down ?

3)

2) Not fully thought through. What was your thought - to mainly to prevent drilling the main frame structure I guess? Joostie already had some holes prepared in a previous CAD file. So maybe adding more beams or a lasercut plate in the area of height adjustment could decouple the adjustment pins from the main structure.

I just finished reading the whole thread from the beginning, regarding the development of the arbor injection molding machine. I am in the beginning of the process of designing a precious plastic shop, most likely going to the injection molding workshop way and from my previous research as well, it looks to me that an arbor machine will indeed be an improvement over the first lever PP injection molding machine. I really appreciate and like the way the development goes on, the community involvement and also the modular designing approach for the final machine.

Well done Joostie and team!

I understand that it is just recently since the prototype model has been made, but i was wondering if there is maybe an approximate date for the release of the blueprints, even in beta. I would like to give it a try and built an arbor press myself..

I have some experience in designing but mostly in more practical terms, in order to be able to feedback or suggest about the machine, through the discord conversation. A small secondary input/suggestion though of mine, would have to do with the aesthetics of the machine, and more specifically regarding the electronics box, that seems a little bit "unbalanced" to me. Maybe a more vertical orthogonal box would look better, if it wouldn't affect the technical aspect of the electronics arrangement.. I will be following the channel, see the progress and help if i can by any way. Keep it on! ⭐

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@Carolina and I visited @Joostie this week in delft to check out how the arbor press development was going

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Hello hello! Here are some of the injections with did during the first tests with the machine!

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on the latest update on #🔥work-in-progress i mentioned a mould made by @Fritz @easymoulds that we used to run some tests. This is how it looks like and the furthest we managed to go with the machine at 270°C with PP. What do you think??

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Carolina

on the latest update on #🔥work-in-progress i mentioned a mould made by @Fritz @easymoulds that we used to run some tests. This is how it looks like and the furthest we managed to go with the machine at 270°C with PP. What do you think??

That is crazy good! I don't even have the necessary experience to say that yet. I am curious about a test with thin parts too (edited)

Carolina

on the latest update on #🔥work-in-progress i mentioned a mould made by @Fritz @easymoulds that we used to run some tests. This is how it looks like and the furthest we managed to go with the machine at 270°C with PP. What do you think??

ha! it didn't even use the screwed mould attachment, is that done just by the spring thing Joost invented? Seems wonderful, no flashing, no nothing, just looks like a perfect product, by the photo (didn't it have air bubbles issues at that high temperature?)

Carolina

on the latest update on #🔥work-in-progress i mentioned a mould made by @Fritz @easymoulds that we used to run some tests. This is how it looks like and the furthest we managed to go with the machine at 270°C with PP. What do you think??

PP is save to melt at 270 C ???

@Alex_recycles and creates 230c is my sweet spot, but it really depends on the machine, sensors, heat distribution and melting period between injections.

Carolina

on the latest update on #🔥work-in-progress i mentioned a mould made by @Fritz @easymoulds that we used to run some tests. This is how it looks like and the furthest we managed to go with the machine at 270°C with PP. What do you think??

Was the mould cold or warm? what was the diameter of the channel out of curiosity?

Alex_recycles and creates

PP is save to melt at 270 C ???

Exactly it always case by case per machine, not because my machine was at 270 that means the plastic was at that exact temperature too

and of course we kept an eye on the plastic consistency to make sure it wasn’t burning

Rory - Sustainable Design Studio

Was the mould cold or warm? what was the diameter of the channel out of curiosity?

Mould was cold at all times and about the diameter good question, @Joostie or @Fritz @easymoulds might be able to answer that question for you

The channel is circular and has a diameter of 8mm! The flowdistance of the testshot @Carolina shared is over 800mm long

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blastic

ha! it didn't even use the screwed mould attachment, is that done just by the spring thing Joost invented? Seems wonderful, no flashing, no nothing, just looks like a perfect product, by the photo (didn't it have air bubbles issues at that high temperature?)

Yes, you just place the mold under and start injecting! It doens't work flawlessly yet, but we're working on that

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Joostie

The channel is circular and has a diameter of 8mm! The flowdistance of the testshot @Carolina shared is over 800mm long

What was the total length of the mould?

(edited)

1300mm!

Hello everyone! I just wanted to share with everyone the feedback we gave to Joost during our visit in Delft after doing some tests on the machine and getting the feeling of it! We made this document

https://docs.google.com/document/d/1UGnLMcGz7ouN3qiE7-bjqk7WH0e9UuO3Pa8IMY4lblA/edit?usp=sharing with every part of the machine we discussed about on-site and the different ways we think we could improve it for the next iteration, I've also added (in red) some new thoughts and ideas that didn't came up while i was there. Feel free to take a look at it and comment here in the channel so that we can start a conversation and maybe get some more feedback and suggestions

Here's the link to the grabcad partnerspace for those who dont have it and want to take a look at the current 3D model (this one has the milled gearbox, not the laser cut one - thats the only difference compared to the prototype we tested) https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC (edited)

Arbor press - 1st prototype feedback

️ - Top priority

️ New questions/ suggestions (from PP) Main findings 1st prototype test: General observations Locknuts should be used everywhere Max 2 different thicknesses of laser cut plates (min. 1.5 mm) Mold table redesign Arbor current model Current height-positioning is not...

GrabCAD

The GrabCAD platform drives additive manufacturing at scale through connected solutions, including GrabCAD Print, GrabCAD Shop & the GrabCAD SDKs.

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Let me know if you can open the doc please!

Carolina

Let me know if you can open the doc please!

Docs are opening fine

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Carolina

Hello everyone! I just wanted to share with everyone the feedback we gave to Joost during our visit in Delft after doing some tests on the machine and getting the feeling of it! We made this document

https://docs.google.com/document/d/1UGnLMcGz7ouN3qiE7-bjqk7WH0e9UuO3Pa8IMY4lblA/edit?usp=sharing with every part of the machine we discussed about on-site and the different ways we think we could improve it for the next iteration, I've also added (in red) some new thoughts and ideas that didn't came up while i was there. Feel free to take a look at it and comment here in the channel so that we can start a conversation and maybe get some more feedback and suggestions

Here's the link to the grabcad partnerspace for those who dont have it and want to take a look at the current 3D model (this one has the milled gearbox, not the laser cut one - thats the only difference compared to the prototype we tested) https://workbench.grabcad.com/workbench/projects/gcJQXBB81dH4d-bCo2zv4iHRoWEOWUS0MWjRMmH21eG_F1#/space/gcBOt9ndbT0LO7WjkQS0aZ7ZGrrzmJ28W6GPklVQRA4BEC (edited)

nice and analytical review for the parts it covers. well done!

spiros nik

nice and analytical review for the parts it covers. well done!

Thank you

Thanks for the post inspiration!

https://www.instagram.com/p/CjTKw2CPTzu/

realpreciousplastic

Sharing a sneak peek of the work-in-progress open source Arbor Press!

Multiple Precious Plastic workspaces use Arbor Press designs, but for various reasons, no one has been able to fully open source them. So, we’ve started to design an Arbor Press ourselves! With our friendfromleading the way, plus help from our Discord community, here’s a ...

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How is the new machine coming along ?

Alex_recycles and creates

How is the new machine coming along ?

Hello! we havent post any updates yet because since the last update we shared on the youtube video (https://www.youtube.com/watch?v=jWbkIa0ncIU&t=0s), @Joostie presented his graduation project (which it went great :D) and now he is working on the feedback given to him on our last visit. We shared the document with the feedback give to Joost, but i will put it here again

https://docs.google.com/document/d/1UGnLMcGz7ouN3qiE7-bjqk7WH0e9UuO3Pa8IMY4lblA/edit?usp=sharing in case you want to know what he is working on at the moment. As soon as we get the updated model we will share it here ! We should hopefully have a how to by the end of this year

Stay tuned! (edited)

Precious Plastic

Arbor Press Development SNEAK PEEK

Arbor press - 1st prototype feedback

️ - Top priority

️ New questions/ suggestions (from PP) Main findings 1st prototype test: General observations Locknuts should be used everywhere Max 2 different thicknesses of laser cut plates (min. 1.5 mm) Mold table redesign Arbor current model Current height-positioning is not...

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1:18 PM

Also! Big shoutout to @Thomas Peterberns | Johannplasto for donating a beautiful screwdriver

to @Joostie as a graduation present

#buildingcommunity ❤️ (edited)

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Carolina

Also! Big shoutout to @Thomas Peterberns | Johannplasto for donating a beautiful screwdriver

to @Joostie as a graduation present

#buildingcommunity ❤️ (edited)

@callie nice content for sm? Even just a couple of stories?

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Oh ya! Cool community connection. Will add to cal

Carolina

Also! Big shoutout to @Thomas Peterberns | Johannplasto for donating a beautiful screwdriver

to @Joostie as a graduation present

#buildingcommunity ❤️ (edited)

Congrats @Joostie !!! Super deserved graduation & screwdriver

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Partialy inspired by recent developments, i've made my own take on an arbor driven injection machine. It's a good functioning prototype. Still some optimation to be done on the design. My focus was more on making it easy to produce and consts, while maintaining an industrial quality. I will work on a version with a clamping unit also. That's the main part which is missing for the current injection in my opinion. https://youtu.be/fbFZmdAGDio (edited)

PBS Machinery

Manual injection molding machine test

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Peter-Bas

Partialy inspired by recent developments, i've made my own take on an arbor driven injection machine. It's a good functioning prototype. Still some optimation to be done on the design. My focus was more on making it easy to produce and consts, while maintaining an industrial quality. I will work on a version with a clamping unit also. That's the main part which is missing for the current injection in my opinion. https://youtu.be/fbFZmdAGDio (edited)

interesting new concepts! Let's see the unmolding pleeeaase! we love recycled products here

(edited)

hi guys! Is there any update regarding the publishing of the arbor press how to?

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i just see uploaded the arbor machine how to! congrats!!!

and thank you!

Hello everyone!

It’s been a couple of months without any updates, but it was because Joost was starting to wrap up this project after his graduation and after a short break, we started to help and guide Joost in the documentation process of this machine! So now, we are super excited to tell you that Joost's arbor press design is out!

https://community.preciousplastic.com/how-to/joost-arbor-press Thank you so much @Joostie for your amazing work and dedication to this project and everyone (@Arbor Contributor ) in this group that contributed somehow in the development

This machine is still in it's early stage but we are sure that with the help of the incredible Precious Plastic community PreciousPlastic

we will sooner rather than later be taking this design to the next level! So make sure to check out the how to, click on the OneArmy

Useful button and add some comments and suggestions down below of things that you feel can be improved in this design! If you want the @PP Team support and help open sourcing you machine or mould desings, make sure to reach out to @valerine !

(edited)

Joost Arbor Press

Joost Arbor Press is a machine based on the original design of the Injection machine made by Precious Plastic (https://community.preciousplastic.com/academy/build/injection) This machine, solves 2 main problems: Ergonomics, which was directly affecting the user experience and therefore the productivity and on the other hand, the pressure, this ...

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Carolina pinned a message to this channel. 2/28/2023 2:45 PM

We've redesigned Discord with more forum channels so you can easily find the discussion you're looking for

We've stopped all activity here. Don’t worry though - they'll be available until 31st of December 2023, so you can save any conversation you need. 

️ On January 1st, 2024, the old channels will be deleted. Feel free to explore the new channels and start the conversation there!