Melting Plastic and Manufacturing

[Wetmelon]

Hey PF,

I normally frequent the EE portion of this board, but I had a question about plastics and plastic injection molding.

A buddy and I have an idea to create a rather small and specific plastic object in large quantities. We thought that to create small prototype quantities, we could melt plastics and re-pour them into our mold. Is this even possible, or do I need a high pressure to stop the plastics from burning instead of melting?

As for injection molding, what kind of costs are associated with tooling a mold and doing a production run (say of a few thousand objects of volume ~140mm^3 ABS plastic with designs on the surface)? Is there a better method to do what I'm thinking?

 

[Wetmelon]

Perhaps I should re-phrase. I want to use injection molding to produce the item in the post above. I would need to produce only about 1000 as a prototype, but production would require hundreds of thousands (to millions eventually). Is injection molding the right path, or should I look at some other technology?

 

[DanielHillery]

The injection molding cost depends on the size and design as well as the parts needed for creating the molded material.

 

[RocketSci5KN]

Injection molding is certainly your best bet. I've worked with a local company called BOJO (http://www.bojoinc.com/) who can answer all the questions, make molds, and make your parts. The mold cost will be based on the projected volumes, as one mold could make 1-up or 100-up of these at the same time. Ask for Matt.

 

[Wetmelon]

Actually, in the period since i posted this, I though perhaps extruding the plastic, rounding the end, then cutting to length would be more effective. Any thoughts?

Note that the pellet is 6mm diameter (approx)

 

[RocketSci5KN]

In high volume, nothing beats injection molding.

 

[chemaddict]

If you do try to make them in your mold, there are certain types of plastics/polymers that can be melted. Basically you have thermoplastic polymers and thermosetting polymers. Thermoplastic can be melted and reformed, but don't use a direct flame or they might catch fire. A simple one to use depending on what it's used for is Polycaprolactone (google it) because you can essentially melt it in a hot water bath. Anyway, this is all just fyi. Good luck!

P.S. Polycaprolactone is sold as polymorph, shape lock, and a couple other brand names.