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Mould Design Community, what if…???
- This topic has 122 replies, 39 voices, and was last updated 1 year ago by
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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
Hi there,
I have been looking in to making moulds for a while and think a mould makers network is a great idea.
The easiest and cheapest option I have found is to post on a CNC forum like the one below and see if anyone in your area is keen to help.
Scrap aluminum engine blocks can be machined to make large moulds or a DIY furnace can be built to recycle cans into a machinable block.
Free 3D design software like easel is perfect to help make any product imaginable.
I hope this is of help.
https://www.inventables.com/sessions/new
https://www.inventables.com/technologies/easel
after reading all the posts by everyone and it has been going on for over a year has anybody seen the 3d printed solution to this thread.???
Also we need a place where we can do instructional videos on “how to” make moulds just like @davehakkens has done to bring all this together.
Found this cheaper/faster method of creating a detailed mold for injection molding, or most other plastic forming techniques for that matter:
Epoxy Mold
A hard epoxy is used for the actual mold which is housed within a stronger aluminium shell.
I’m thinking one could build a similar shell with some sheet metal and create an attachment for Dave’s injection molder.
@dzspain, yea I’m looking to test some wood with a resin coating, hoping the surface will be smooth enough (Assuming that’s what plastic requires to not adhere). I’ve read that polyurethane works with plastics though, will test that too…
and about finding some industrial designers for the project.. I’m currently in my final year of studying industrial design ^^. This project is something I’m really interested in pursuing!
and output products : they are both PS Cristal, translucent (sourced as single-use transparent cuttlery) and black (sourced as single use black platter)
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Welcome @paulenglish and @redgurrillia to the topic and thank you for your help and ideas.
@uaneme, there’s a lot of tutorials and other stuff about green-sand and aluminium casting on youtube and other sites, as Paulenglish shown to us (thanks Paul, I didn’t know about . I want to suggest you to visit this guy’s channel, he’s very active on home-made casting https://youtu.be/GXSCx50LlNo.
Redgurrilia, I have no information about plastic contamination in the so called “third world” and I neither know about if Dave Hakkens was thinking precisely about this part of the world when decided to launch this project but… anyway, the so called “first world” is the main plastic consumer and consecuently the major plastic trash producer. Maybe the original idea would been focused to “under-developed countries” but there’s a lot to do in our, so called, “developed-western-first-world”.
On one hand, sand casting is a very ancient technique far beyond 60 centuries back in time, babylonians, egipcians or greeks used both in art and militar fields so I think it could be easy to keep it in use anywhere as sand, like aluminium, is one of the most common materials on Earth.
On the other hand, sand casting technique is enought to build a long lasting mould with a very low tech materials as wood, wax and others so I think it could be definetely used anywhere… also in the “western world”. The “pain-point” of the process, to me, is about the technical specifications for aluminium casting and it’s handling through the casting process. Extraction temperature or the right percentaje of flux aditives are very important for high quality aluminium production from recycling, but it has no real effect on a home-made basis production, here or there.
Finally, I guess that maybe we are making a mistake when thinking about the “third world” as “helpless”, “unable to do somethings” people. Let’s see one of many examples from Africa, for instance. As they’re, unfortunately, receiving the major of our electronical waste there’s a huge electronic components availability that they transform in amazing machines and high-tech solutions http://hackaday.com/2013/10/13/3d-printer-made-from-e-waste-in-africa/
They’re also connected to the Internet, there’s also a large number of NGOs cooperanting on the field like “Engineers without borders” http://www.isf.es/ an many many others that could link every part of the puzzle.
Hi @birdynamnam and @uaneme, thank you to join this discussion topic.
I’ve been studying the mould making, just in the theoretical level, and I agree with birdynamnam about the use of thermal resistant silicone as a possibility but I haven’t made any test at all, on the other hand, what I have seen the most of the times in the plastic production manufacturing is aluminium moulds and I guess it is about two very important things:
1. It is hard enought to guarantee a long lasting use, and
2. It can be cooled easily as it has a very high thermal conductivity (a characteristic that silicone has not)
The problem about handling the aluminium to create moulds, even by can recycling, is that you need a foundry to cast the moulds… also when we’re talking about a very low tech requirements (refractary materials, sand, coal…) maybe to produce aluminium blocks to process with a CNC machine… there’s several questions to consider as energy consuming, tools, security and facilities… nothing that can not be solved but something to consider seriously.
On the other hand, there’s a technical knowledge required to produce solid, useful and productive moulds. This knowledge is avaliable on Industrial Design’s profesionals and students and so I think that the key point is to build a Mould Designers’ community and plan how they can participate in the production profits… maybe a fee for each mould made…
In my point of view, if there is a few moulds avaliable for basic items production, it would help A LOT both the producers and designers start-up. If there is also a considerable number of mould’s manufacturers around the world, a very low fee per mould design could mean a very attractive revenue for designers and a very accesible cost for manufacturers, what means, finally a very competitive cost for final users.
I’m just wandering if my thoughts makes any sense and could be helpful for the Precious Plastic project.
By the way, I’m in Valencia but unable to move to anywhere as I’m attending some courses for professional training. Hope you enjoy Barcelona, birdynamnam, it is one of my favourites cities in Spain.
Lots of people here are talking about how, in industry, the normal way to make a mould is to CNC a block of aluminium but how CNC machines aren’t that commonplace especially in the third world.
I’d strongly recommend a visit to http://www.homofaciens.de/
Norbert Heinz has an ongoing project aiming to provide education in machine building using everyday materials and simple tools. His CNC Machine V3 has a lot of potential and could me the answer to mould making problems.
http://www.homofaciens.de/technics-machines-cnc-v3-2_en.htm
I intend to mass produce a specific design of a piece of plastic. I have looked on Internet around the whole country to find the best way for a fast prototype. It seems that all professionals are using silicon, which they frame later with a wood or metal frame to accept pressure. They charge a lot to do just that.
Look at that video, it shows how easy it seems to be, to DIY those molds
I am now convinced and I am looking in the market for the best silicon casting material available in my country (France)
Aluminium moulds
One aspect that I do not believe has been considered is that many people involved in some way or other within the open source community are usually very willing to help each other out. Many individuals became aware of the open source model due to computer software such as Linux. The open source concept has expanded into other sectors – one being the project by Precious Plastic.
While much collaboration is found within open source software development, open source projects do need to network more closely together. Open source software uses the modular design concept – so why not adapt it to plastic moulding?
Various 3D open source software applications have been developed and some individuals have become experts at using the software. Others having an engineering interest have developed LinuxCNC while others have converted machines to be controlled by the software. There exists an entire open source community out there that include experts in 2D drawing, 3D modeling, CNC machining and finally those involved in this project. (Note that the info within certain 3D modeling software can be converted to g-code which a CNC reads as instructions).
I am convinced that the resources for metal moulds lies within the open source community. Many individuals who have benefited from open source projects have a desire to give something back to the community. For example, the open source Hydroponic Automation Platform Initiative (HAPI) uses the open source Raspberry Pi miniature computing platform and also the open-source electronic prototyping platform Arduino. The HAPI project compliments my initiative in Africa which has been the development of a highly adaptable modular hydroponic system which if all goes to plan will be released as an open source system during 2017.
An engineering shop usually has very expensive capital equipment hence high recovery costs based on time. Furthermore, the people working for such a company are usually highly paid. In contrast, an enthusiast that has converted a milling machine or lathe to CNC and has it at home using open source methods should be supportive of a different open source project that converts plastic waste. The same applies to an open source graphic artist. By understanding the motivating force behind the open source model and embracing it yourself, you not only receive, but give back to the community.
As a last point – different open source projects can be viewed as modular components that can be arranged together for a common objective. By networking and consolidating the resources of different open source projects to ensure ultimate success (e.g. the greater availability of more resilient moulds) will mean more waste plastic being turned into useful items.
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.
I thought it’d be great to consolidate and organize this info on the wiki. So I added a Mold section and used most of the info found in this post. Feel free to start adding more content.
http://preciousplasticwiki.herokuapp.com/index.php?title=Mold-design
I also went ahead and started a group on Thingiverse for Precious Plastic. Not sure what the process for joining is, yet. I wish I could just make it public, but not quite sure how. Maybe you’re able to submit a join request or something. Or, hopefully it is public. Check it out at http://www.thingiverse.com/groups/precious-plastic
So heat resistant silicone definitely works, my partner has used it with in an oven melting PLA. I’ll check how high it went and the brand of silicone she used. For injecting with it, I think coating it with plaster or using some wrapping would be necessary, bicycle inner tubes for example.. let’s see, as the lack of conductivity might well be an issue.
Aluminium would be better for repeat making and with higher levels of details. This is something I am going to explore, whether directly getting a pattern maker to fabricate via cnc or sand casting. @paulenglish that technique is really cool and is another thing we want to explore. More hours in a day needed.
Getting several patterns made at one time would certainly reduce costs and allow people who don’t have direct access to such facilities to be involved and receive moulds. I will certainly post up any moulds I plan to have made before I do so to see if there is any interest.
@uaneme I think clay might not be strong enough, but it is worth exploring as it would be able to be reused if rehydrated and reworked correctly. Another option would be to use a strong plaster, this could be effectively done as two part mould around a master and also has the bonus of being able to sink a bush (which connects to the thread on the machine) directly into the plaster.
One thing that might need consideration is escape vents for air as the plastic is injected. I have asked Dave about this directly and he says he hasn’t needed to use them with his moulds, but I imagine as pieces get bigger it might be problematic.
I have test injected onto plywood (not into a mould) and certainly it sticks to it @timslab I didn’t use a release agent however, but polyurethane or a resin coating might work, the only issue being the heat of the melted plastic as it hits the mould.. @dzspain as you say, using a resin mould could end with a mess of melted resin and plastic!
@uaneme Regarding CAD and file formats, I don’t have much to offer as I use sketchup, which is fine for my needs, but as you say rubbish for exporting to relevant file types for CAD.
I also agree that to maximise our labours and recycle the most plastic possible we need input from those which plastic at their disposal but who lack the means to convert it – due to problems with moulds for example.
Fusion 360 is something I’ve played with a bit and is a great, FREE, program which may be of help..
http://www.autodesk.com/products/fusion-360/overview
Thanks to everyone for the links, I’m going to check them out. When I have a bit of spare time and our injection moulder is completely ready I’m going to make some tests with timber and resin-coated timber moulds. Will be sure to let you know how I get on!
Bertie
waiting for it to dry i might wait 24h to be sure that it’s fully dry then i’ll post un update. I compressed it to be sure that the silicon goes all around the case.
Edit : after thought i should have put some all around first then place the case in the middle. anyway i will see
I work also with silicon mold.
But never didn’t them myself
It’s the first time ever for me but i felt like it was worse it to give it a try
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Yeah the whole idea is to be able to send your printer file to anyone in the world and they could start making it. ( if they have the machine and extruder of course)
here is the link for what the idea is based on https://www.youtube.com/watch?v=ZTju-EH22uY&t=777s and this is why I’m so excited at the possibilities of this.
look at this article
Hi everyone, I finally could make it to the latest replies since I started reading yesterday 🙂
You guys had a lot of ideas and experiments about mold making, using alternative materials and processes. It was very instructive for me, so thank you all 🙂
One thing I was thinking about and might look easy to make… Some small size aluminium molds for injection or extrusion can be duplicated and regrouped into one larger mold. it implies some additional tinkering and redesigning how mold parts would fit together, but if done this can allow to mold many pieces at once.
Is it possible to produce much wider molds (perpendicular to injection/extrusion nozzle) to produce many pieces at once using a runner and gate system, just the way many small Lego bricks are manufactured in one mold ? (see pictures)
Are there any technical limitations for the v3 PP machines to perform with such molds ? maybe the larger mold surface will cool the injected/extruded plastic before it spreads to the farthest regions from the center…
@davehakkens any clues about this ?
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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.
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.
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.
Yeah! You go! Congratulations @birdynamnam and @paulaortega!!!
@robksawyer, I didn’t know about the wiki 🙁 and it is fantastic to have one! Thank you so much for taking care of the knowledge in this topic!
Thank you @richoz27 for this comprehensive video! It’s very illustrative!
And thank @davehakkens to honor the topic with your participation.
By the way, I’ll start with the furnace for aluminium casting. I have some metal barrels, sand, paris gypsum, fireclay… not for the whole thing but enough for a good begining.
I’ll take some pictures tomorrow.
Hi everyone! As @birdynamnam mentioned, we’ve build an injection moulder and today I finished the first mould that we’ll try (see pic). I’ve use heat resistant silicone rubber wrapped in plaster bandage and a strong stone plaster on the top to set the bush. I know already that the rubber will take the heat as I’ve been testing this for months in a lab oven before the injection moulder was ready. The question is now whether we’ll need to add vents, if the ‘bush set’ will be strong enough and also if we’ll get it right with the temperature and pressure.
Paula
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Would .ODF (open document format) be usable for any of this?
Or is there a better open format foe Blueprint material?
What CAD format is most compatible? STEP is best compatible between AutoCAD and FreeCAD. But i don’t know about other CAD programs. Sketchup also has horrible output when it comes to compatibility. My CAD skills are still very basic and FreeCAD is the only application that’s is actually usable to me.
Blender i also can manage but thats less intuitive when it comes to exact measurements. For more organic shapes blender seems to be the better tool.
OSE has a a nice set of machines, mainly for farming and building. There should be a project like this for smaller scale production (desktop size)
Also have a look at this
https://sites.google.com/site/3dprinterlist/other-machines
There are many interesting little machines on that list as well.
Is it possible to export the AutoCAD files as STEP? That might eventually draw in a few FreeCAD users. Then the designs can be discussed on the FreeCAD forum. etc. And the then the compatibillity from .FCStd could become an issue. And then AutoCAD users can be enlightened about how flippin annoying it is when you are forced to work with non compatible file types.
I’m currently playing with paper-pulp to get an idea about making molds in a low tech style. and it tuns out to be way more difficult then i expected.
But very educational 😀 and paperpulp is a nice material to work with.
Its a bit like plastic, but doesn’t need heat, and a lot more time for the water to evaporate.
@uaneme you are definetely right! Cad files are just not enught and maybe blueprints should be added to the repository.
About tools worldwide, let me introduce the Global Village Construction Set from The Open Source Ecology group. There just amazing when talking about machines.
Many thanks to share your thoughts about CAD file limits 😉
That’s nice, thank’s for your ideas!
@uaneme it is a cool sugestion the use of clay, in fact I’m thinking that maybe it could be not a great material to work under presure directly on a compresion machine as, if it’s not baked, it could peel by use, but it is really easy to work with, it’s cheap and there’s worldwide. Good point!
@n-w-b, you get it! I think that there are many designers that could find a professional career within this project, and making a big contribution to its development at the same time. I’m agree with the idea of to give designers a space to show their work to the mould builders it’s a must. What about to spread the project over the design schools and over the general population to help them find each other on the project website? Does anyone knows how this website is managed? To whom should be directed this proposal?
Welcome to the topic @timslab. I’m very trusting in the epoxi potential and wood… but also worried about how temperature could affect the mould when working arround 250ºC. Can epoxi ignites at this temperature, could it be safe to human’s breath while using? I guess that these are questions to solve on the ground by testing the materials. Good for you studying design! There’s a lot to do yet in this area! How can we involve your colleagues into the project? As designer, what do you think about the idea of a “Designers Community” and a mould designs marketplace to feed the mould makers worldwide? The idea of to receive a little payment for each mould maker could it be attractive to a designer?
Thank’s again for your feedback on this topic
Great idea. I think it is posible to make some sort of library. The only thing is you should just share are the plans of it. Make it so that you can read some info about it. Include a few pics from a few different angles and then if you like it you can just download the CAD file. There is free CAD software avialble so there is no problem with that part.
The best way to do this is to make a another page here under the Community tab. Make it a bit like the homepage with like the bloks of info but a bit more structured. Then if you click on it you will be guided to the page that contains all the information. A few pictures, some info about the mould and the product you can make with it. Bit like thingyvers or the libary of Sketchup.
Hello It’s been long time since I haven’t follow up on this.
So the main reason it’s that is has been a fail for multiple reasons, I ll try to explain my tests so you can learn from it.
The silicon molding went perfect I clean it up after it dried with a blade.
So i my first 2 or 3 attempts to pull plastic into it every I failed because the mold was to cold so every time I would push some plastic into the mold the plastic would get lower in temperature and get harder so it would not fill the mold.
At the end i decided to put the mold into the hoven but the mold wasn’t supporting the high temperature and bubble would create in the mold deforming the mold.
So to conclude story is to be continued….
I’ll try again with silicon with a higher temperature resistance to melt the plastic directly into the mold will se how it goes
@dbougas here is the mold.
First learning is to not use old leather case and more of a plastic case. It disintegrated itself into the silicon.
The result is quite impressive the mold looks great and very precise, looks strong enough not to bend when pressing the HDPE into it.
My question right now is should i remove the (rounded) edges as i fell like the HDPE won’t flow into the sides and make the rounded finish edges at the end.
What do you think ??
Learning number 2 : next time I ll try with iPhone SE case as there is way less rounded edges 😝
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