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Mould Design Community, what if…???


This topic contains 121 replies, has 38 voices, and was last updated by  Dan Shirley 7 months ago.

Dario Zanon dzspain

Mould Design Community, what if…???

10/05/2016 at 12:16

Hi everyone! I’m absolutely excited with the idea, it’s a great one and with a big set of tools to go on but I just find a “weak point” about all this stuff when we pretend to recycle and reuse the plastic on Dave’s machines… MOULDS!

There is nothing to do with an extruder machine without a mould… so I’m wondering how can it be fixed and it is not a simple matter.

The first “pain point” is about mould design. It is not only a matter of shape but also a question of architecture as the final product should be “nice and useful (durable)” so I want to invite everyone on a discussion about “design inteligence”. My point of view is that the “designers knowledge” should be implemented on the project and maybe to create a “Plastic’s Design Market” where any producer could buy or borrow a plastic mould design to made.

On the other hand, once there’s a mould to be made, we should talk about aluminium recycling for greensand casting or CNC milling; so there’s a need about aluminium casting techics, technical knowledge and technical skills to provide.. but also CNC machines building, stepper motors control and CNC software for mould designs making.

I think that it could be great if we find the way to merge design knowledge, mould design libraries and a mould makers list to give this project a “ready to go” state.

About mould casting, I would like to advice about how useful and efficient could be a “mould makers network”, as it is needed various requirements to produce quality moulds for long lasting use and production such as machinery, knowledge, space, and so on… maybe to arrange a regional clustering could be a must in order to maximize start-up speed and reduce production expenses to someone’s project.

Do you want to join the discussion?

Thank’s for your attention 🙂

Edit, Moved to PreciousPlastic forum

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21/06/2016 at 09:42

@uaneme The brick I did needs work, it would need to be mostly hollow I think to keep wall thickness consistent and reduce the amount of plastic used.

First thing is to get the function right, then make the mould easy to make (design for manufacture). There is a lot of plastic around and its basically free.

Your STEP file works fine for me, its a format that most CAD programs can use.

Using CAD, you just need to sit down and play with it to learn, thats how I started.

Lets talk about it here instead of derailing this post any further 🙂

Interlocking Brick Design

22/06/2016 at 06:17

@robksawyer thingyverse is in a way a nice platform to promotethe project, but their terms are not just bad, they are evil.

I think Youmagine has more respect for the creator, and human readable terms and conditions. (the only one on the list so far that can be understood with needing a degree in lawschool…)

Do you have a picture of the LEGO + silicon mould? (if yes, please add it to the wiki!!)

26/06/2016 at 11:57

wow @robksawyer amazing job on the wiki! Looks very clear, thorough and organised. Keep up the good work 👌

29/06/2016 at 00:47


This thread is growing a bit long. This forum does not seem to make new pages so people need to scroll a lot to get to the bottom.
What if we make a new topic. Same name (part 2) just to make it more usable.

29/06/2016 at 22:22

Thanks @davehakkens!

03/07/2016 at 22:03

Welcome @winbidtm, many thanks for your help offering on CAD @richoz27 and yes, you’re right about quality producing to make the project as useful as interesting to everyone, thanks @bianca for your input and congratulations for your jewels they look nice! @richoz27 posted a video upwards about injection and @paulaortega and @birdynamnam are experiencing with heat resistant silicone moulding, @andyn gaves a brilliant idea to simplify the process on dayli ovens, thank you so much for your inputs and suggestions @andyn.

Thanks @uaneme for your view and concern about the best practices for CAD modeling and @richoz27 inputs too. Great job @robksawyer!

I’m still quite busy with my training course but I finally made a little furnace for aluminium casting, not finished yet, I should remove the inside mold and make the melting pot.

@uaneme, about to split the topic, I think that it could be nice as this one was wiling to be focused on mold designers community instead of molds making and trouble fixing but… you can see, human spontaneity has its own way and I’m grateful for all the great ideas added here. Maybe we should ask to the rest of users what they think and how they would like to organice the discussion topic 🙂

07/07/2016 at 05:42

@uaneme you said you want simple cad for everyone, then you talked hardware and operating systems. Are computers that are not attached to the Internet widely adopted in third world countries? If so, without the Internet how would these people even learn about the previous plastic project in the first place?

For CAD to be truly accessible for all does Web based make the most sense? Even a homeless person in my country could go into a public library and access the Internet to use tinkercad. With no experience I’ve found tinkercad to be easy to learn and create with. I believe it’s worth a try for anyone anywhere, check it out: http://www.tinkercad.com

07/07/2016 at 20:16

@winbidtm I’m glad you asked this question!

Operating Systems like Debian, Ubuntu, Mint, (and many others) you can download (at no cost) and burn on a CD, or flash on a USB stick. So it is still a good option to install a fresh (and fully supported) OS, without malware, that is much lighter on the CPU then windows.

I know for instance a guy who immigrated to Kampala, and over there he installs Ubuntu on older PC’s that struggle with windows (Windows7 is way to heavy for older hardware) So in third world countries PC’s actually exist. And people know how to delete outdated XP, and install something thats a bit more up to date.

And true, it’s not mainstream… And they have no broadband.

But there are Internet cafe’s, USB sticks, CD’s, DVD’s, Android phones with filesharing apps. Those people can get files from the net. But they don’t have Autocad, and if they do have autocad, then the pc is most likely far below spec.
And Autocad probably not as a legal copy. So that tthen already pot’s them in a dangerous position with the law. Corrupt law enforcers are also common in those area’s. So it’s better to be one step ahead.

Those people should find Precious Plastic without too much trouble. We should try to let them know. I emailed the guy in Kampala. And he told his friends about it. Not sure if anyone is on the case yet but i know the word is out. So if you any of us knows someone who may be near a large source of plastic then just say hello and email a link and a few images from here. 😉

Web based Cad apps do only make sense if there is a RELIABLE broadband connection. In Kampala this would not be an option anytime soon.
Also a site like this should hav a low bandwidth version that does not pre-load all the pictures. Just to be more user friendly for people on slow connections. @davehakkens Please consider some option like that!

I have seen thinkerCAD on youtube, but unfortunately it does not woth on any of the Linux machines i have tried so far. (Probably proprietary webGL issues? not sure though..) So then those people need expensive Windows or Apple boxes. So that puts them also at risk of being robbed. (yet another thing that happens in those places)

On the other hand, if there is a library, or internet cafe with reliable connectivity then why not use tinkercad. But then comes the question: Are tinkercad files compatible with other applications and viceversa?

They should still be able to open the files even when there is no internet. (Can tinkercad do this at all?) So personally I would avoid online CAD apps at any cost, since i know how horrible the connectivity is down there. A simple chat program already has enough trouble to send a few words back and forth. 🙂

I’ll add tinkercad to the wiki, (unless someone already done so…)
I’ll put online CAD apps in a separate table. With a few pro’s and cons.

There’s new online CAD app that seems to be very user friendly, 3D shape? shape …something, can’t remember the name, i’ll have to look it up.

Hmm another thing with online CAD apps, you need to rely on others, Library needs to be open (no late nite cad work), there need to be a free table etc.. and when you go home, then there is no way to make a few small changes.

But yea, it is an option that doesn’t need a big budget.


09/07/2016 at 13:03

Brilliant comment @uaneme! I’m full agree with you. Technology is everywhere and it can be useful with the appropriate software. You’re on the right path. Congratulations for your wiki work too!

Here is my little furnace… still need to remove the inner mold and I just get that must had to remove when it was still wet… if someone tries to do it, don’t let it dry before remove the interior mold!

09/07/2016 at 13:04

Full closed

10/07/2016 at 22:33

@dzspain Hehe the cat already approved the furnace.

Thanks for the kind words, though i’d like to forward them to all the people who develop Free Software for making this possible, i only show that it is available, and actually works. (almost as good as insanely overpriced software)

Good to see that there are now also online CAD editors, but after reading one of daves last posts (he mentioned very bad internet connectivity) i’m sure that this is no option for countries where the infrastructure is more fragaile then what we are used to. And with the current financial crisis we can see that our internet standard is also coming under thread, not to speak about Netflix’s attempts to undermine our net neutrality. Then only the rich people can enjoy fast-lane connectivity. And that would eventually render online CAD useless even for us. So for those who want to use that, enjoy it while it lasts, but keep in mind that there is Free Software that still can do the trick.

Now you can also start collecting soda cans. 🙂

How much aluminium can you melt in one go with this?

30/07/2016 at 12:14

Hey @dzspain @uaneme and all,

Big apologies for the radio silence. Looks like you all have been making fantastic progress though – the furnace looks great!

So, like all us, I’ve been really busy with work and the injection moulder has been languishing in a corner of the workshop looking rather sad with its electrics box opened up. My wiring has let me down and I need to reassess what has gone wrong as now a band heater isn’t working!

Hoping to do some work over the next few weeks as @paulaortega is excited to try her moulds!

Back soon!


25/08/2016 at 19:29

@uaneme It’s a privilege to meet people like you. You brave, kind hearted man 🙂

@birdynamnam, it’s nice to see you here! Same as all the folks here!

I’m on vacation, enjoying my family and friends on the hot sunshine days of western Mediterranean sea. Coming back to rutine in… six… five… four…

04/09/2016 at 01:50

Has anyone tried plaster casts for molding? Dental die stone is quite hard, I wonder if it would hold up under the pressure to be used over and over again.

24/09/2016 at 06:25

@trishkabob I came here just to talk about that exact same thing 😉

@dzspain @birdynamnam @uaneme @paulenglish @redgurrillia @timslab @n-w-b @richoz27 @davehakkens @robksawyer @paulaortega @winbidtm @andyn @bianca

The guys from Precious Plastic México are currently testing molds made with plaster, and seems to work perfectly. The advantage of using plaster for moulding is that plaster is super cheap, non-toxic and the moulds can be easily replaced if one breaks.

Look at their project here:

Here’s the official post about their project on the forum:


Injection Molding Tests

24/09/2016 at 10:59


Looks like a nice idea! Plaster is a great and pretty cheap solution.

Can you maybe make a tutorial for the wiki?

Keep up the good work!

24/09/2016 at 11:03

That would be a job for @andresornelas, he’s the one currently experimenting with plaster

24/09/2016 at 21:47

That’s GREAT @xxxolivierxxx! Thank’s for the suggestion and link and congratulations to Mexico!!! 🙂

25/09/2016 at 20:43

@xxxolivierxxx Thanks for the cross-post

@dzspain Thanks! I’m glad our work is helping others. Huge shoutout to my brother @nachonaranjas who’s been hard at work to get our machines going!

@n-w-b I’m having issues creating an account in the wiki, but I’ll definitely post an article about our molding techniques once that’s sorted out. I’ve emailed [email protected] for help…

In the mean time, see the info in our topic and feel free to ask questions there! We’ll post some more details and photos there soon.

Injection Molding Tests

27/09/2016 at 17:13

@xxxolivierxxx and @andresornelas

great to see how well plaster works!!!

Looks like a great way to pirate some existing plastic objects. 🙂

If a plastic object is broken, copy the broken part in a plaster mould, and replace the broken part with something more colorful.

27/09/2016 at 18:28

@uaneme let’s call it replicate 😉
Pirate sounds as if we were doing something wrong, and we are just trying to save the world 😀

27/09/2016 at 20:16

@xxxolivierxxx Thats the whole thing, the ones who came up with the term piracy never understood dat the original is not stolen. The original owner still has the original. And the copy may eventually be improved after finding the weak spot.

Add graphite (for strenght) and you may call it a ‘carbon’ copy.

But i used the term pirate for a different reason. Pirates live a soverein life. Offshore in no mans land. The ‘cyberspace’ from the past. In a way a free life. Some of them behaved bad, but for every bad person a good one needs to exist. (natural balance) We can’t help it that history books only remember the bad people.

OK enough of my plastic philosophy… 😀 Lets save this planet

14/10/2016 at 00:31

Update – @paulaortega and I had a successful injection into a plywood mould, but unsurprisingly you can’t get the plastic brick (PLA) out once it has hardened, even with lubricant beforehand. Whether draft angles on the mould would have helped enough I’m not sure.

We also injected into heat resistant silicone wrapped in plaster bandage. This was successful until the mould exploded at a weak point and sprayed molten PLA all over my (plastic) workshop door! It aint coming off.

More experiments to follow with sturdier, solid plaster moulds to be sure, especially after seeing @andresornelas‘ successes.

Also found a small casting company nearby so may look into getting aluminium moulds made up too..


16/10/2016 at 03:29

Hi Mould Design Community,

I wanted to compile a Wiki list of mould provider/maker and alternative mould making method and and it estimated price and it location listed in the community. I myself researching the alternative affordable mould making material and method. I’m planing investing in a small CNC router.

I tried to create a wiki account and it return Database error “A database query error has occurred. This may indicate a bug in the software.”

17/10/2016 at 19:04

Just a thought guys, I also work with wood, and I think it could be used as a good mold, for a smooth surface, you could use car body filler to flatten the wood fibers/grain, and once you have the shape and finish you need then use a car wax. Just a thought.

17/10/2016 at 23:05

Hi, I find very interesting, I’m starting the project with a friend and time go a little slow, but eager, my friend is designer pieces, we will comment.
a greeting

08/11/2016 at 12:48

Hi Tian here new to chat and forums.Everyone has great ideas and none of them are wrong. As a foundry pattern maker by trade can see a lot of you have done tons of research in regards to moulds. In our industry we make moulding equipment for metal castings using wood, epoxy and polyurethane resins and sometimes types of steel as well. My main suggestions would be if you aim to produce low volume use cheapest possible material like plaster, or wood. Plaster has the added benefit that your mounting assembly to join the mould to injector, running or feeding of plastic to desired part can all be cast into the mould, as well as ease of making both halves of your mould match up. A simple wooden frame should suffice to keep the plaster rigid. What will weaken the plaster may be continued heating and cooling and absorption of moisture. But for low volume you can’t beat the low cost of plaster. It may make one part only or 100’s depends how well you look after it. May need to split my posts as moulding and patternmaking have many methods etc.

08/11/2016 at 12:55

Next method, wooden moulds: MDF / Supawood is a resin bonded paper cardboard mulch, most countries its relatively cheap, in regards to moulding and the use of wood, hard woods would be better and last longer with treatment meaning waterproofing paints etc. Problem again MDF / Supawood loves moisture especially the ends that look like a sponge, the outer compressed edges usually can withstand a bit more wear, hardwoods are sturdier but… wood never dies it expands and contracts continously and will always change and absorb moisture as well as give off some moisture, and not sure how heating and cooling in regards to injection moulding would affect it. Again could make one part or a 100, testing would be needed. Main negative point all connecting assemblies running and feeding of plastic would need to be cut or machined in. Using hand tools to do that can work but it’s hard and time consuming. A castable material would be easier.

08/11/2016 at 13:07

Next method I can think of would be a castable resin. http://www.smooth-on.com makes a product called mold-max 60 heat resistant to 294 degrees celsius, and looking at the chart thats higher than the melting temperature of most plastics unless the closest bandheater where you increase temperature raises it more, whereby the resin would become unstable. As with castable stuff easy to incorporate connection assemblies to machines plus running and feeding to part. Easy to cast into a standard type split box etc. But the resin itself has a cost so that cost needs to be recouped if needed from the items made if possible. With this resin method and both plaster and wooden moulds the main drawback as mentioned is cooling the injected plastic correctly to preserve your parts integrity. Not impossible with ingenuity or trail and error testing.

08/11/2016 at 13:25

Last method for now Aluminium moulds. By far the most widely used in the plastic industry as the relatively low cost and ease to produce for high volume works for them – them being big business. These industrial moulds are usually air or watercooled to cut down production time and as such one mould can even spit out 10 to 20 or more parts each time. For us makers, tinkers and hobbyists it would be a huge challenge. The financial implications of producing aluminium moulds would mean you only use it for high production 1000’s of parts plus to justify the costs, as cnc machining or having a tool shop design and fabricate this type of mould is costly and takes quite some time, profit from high production runs usually negates the moulding equipment cost many times over. For the small scale these machines work on even aquiring a small cnc machine and tooling to reliably work aluminium would be a huge investment. Again I may not have mentioned earlier, I have foreseen this problem even before starting to build the machines so at best take it as theoretical problems as all can work if the problem of cost or supply can be resolved.

So on the cost portion cast your own aluminium moulding equipment again not impossible, major considerations in metal casting as it relates to our industry of patternmaking. Metal shrinks as it cools, we call it contraction or shrinkage allowance, for which there are industry standards, which means at least for duplicating in metal you can’t simply use the part itself, you must make the part with all allowances incorporated which could be holes for screws or machining where more material is added, the shrinkage of the metal used as well as the fact that cast metal does not come out the mould with a smooth workable surface, some finishing will always be needed.

My best suggestions will be always use the method or material most readily available to you. If it worked before it will work again, but always be on the lookout for a better, quicker, cheaper or more energy efficient or environmentally efficient method. All the above methods have worked in the past and can work in the future.

Hope to be able to comment more or help solve some of these problems as I end up using them once I have completed my builds.

Good luck moulding guys.

Should you need help clarifying some moulding issues in your research feel free to ask me anytime.

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