Injection molding printed parts set?

Mostly Printed CNC - MPCNC Hardware Development
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Have been looking into desktop injection molding lately.

I am wondering if injection molding printed parts set would be possible , using epoxy molds perhaps .

https://www.instructables.com/id/Home-Plastic-Injection-Molding-with-an-Epoxy-Mold/

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When I get some time I would like to try to create a system for injection molding too. This site is a great resource for building your own open-source machines for plastic production.

 

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What is the benefit of that?

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Briefly , it lets you produce a large batch of objects quickly , while 3d printing in its quicker form (sls maybe ?) takes longer times to accomplish the same number of items.

Problem might arise with molds materials (aluminum for industrial pourposes) .

3d printed molds are possible for home based production lines (desktop injection molding) for a number of uses not larger than 20 or 30 , then the mold gets unusefull and ruined perhaps , so you need to reprint the mold .

https://preciousplastic.com/en/videos/build/injection.html

Nice site , I’ve seen their video on hackaday on start to finish molding project.

 

 

 

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The hard part with injection molding is size and shape. Injection molding is actually pretty complicated.

The larger the part the more pressure you need. The mold itself needs to be heated and cooled as well. That is why they are always doing small smooth thin objects with the hand operated injectors.

The part shape itself is another factor. Any piece of the MPCNC need to have slides or pins to make the holes.

 

I think a much more fun way to do it would be to resin cast the parts. You can mill out the molds or make silicone ones then pour in any resin you think would be best.

1 Like
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Or…Dui is even casting them in aluminum using lost PLA investment casting and it seems to be working really well.

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casting them in aluminum using lost PLA investment casting
Me like Mr Magoo , don't feel confident enough for extra heat emitting substances :P

Resin casting with silicone mold seems reasonable and cheaper than making new molds every 20 injections ,

I am quite sure it (silicone mold) lasts longer since no subject to pressure and heat , so nice idea .

Perfect if you can mix resin with chopped carbon fiber somehow …

… I’ve read somewhere that you can resin cast with abs + acetone , need to check it though.

 

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Abs acetone cast only small parts, with an open top. Has to be able to offgas the acetone or it will just stay a liquid in the mold.