Granulatiing plastic

There are tons of plastics/non metal grinders out there... unless you mean specifically designed for grinding 3d printing plastics? Do a search for commercial grinders and you will find some very good designs and if you check the equipment auctions every month there are always a few that go pretty cheap and are still quite serviceable albeit not pretty or new.

at the auctions they can go as low as 50 bucks for machines that cost many thousands of dollars when new, it's all about looking in the right place at the right time... it's actually amazing how some of the bigger stuff can go as cheap as it does... as long as there isn't a scrap buyer looking at stuff as that can drive prices up.

^^ yes, quite a few are 220/208/480 3ph but I have switched motors before on all kinds of machinery, just up the hp about 20-30 percent for the torque loss if you want equivalent power... however for the type of material we are dealing with you wouldn't need the designed power in fact just running a phase converter and taking a hit on power with the 3ph motor would more than likely be sufficient.

The only reason I stopped with my kitchen blender was that it tore apart the plexi glass bucket. The shredding action was actually ok. To a blender with a glass bucked will do that job well.

I also asked the guys from the perpetual plastics project and they will offer a shredder in the 400$ range as well in the future.

What I also found out was that if you melt you plastic on a baking sheet you get it thin enough for you kitchen blender to be able to work it. Its hellishly loud and you need a sturdy glassbucket but for the lowcost version it will do.

Pics here: http://printnewworlds.blogspot.nl/2014/ … -test.html