I understand that filament solves certain problems that people making the first FDM printers needed to address, but I don't see why every subsequent model has slavishly copied their original design. I want to make a much larger printer than the typical size on offer, using a larger orifice to make bigger and stronger parts more quickly. This would quickly gobble up standard filament by the roll, since my orifice size would probably be bigger than its 1.75mm diameter.

Thanks for the link to the Arburg Freeformer, but that looks like quite an expensive machine. I doubt they'll want to sell me the guts of it to use on my own DIY project. I was hoping someone has put out a relatively inexpensive stand-alone hopper/auger/hotend that I could just bolt on, but maybe that's just a fantasy at this point. I don't see why it would have to weigh an impossible amount, but I'm coming from the DIY CNC router-building world, where it's pretty common to bolt a spindle weighing upwards of 35 lbs. to the Z axis. We use much bigger motors than the tiny NEMA 17s that are popular on 3D printers, though.

I find it hard to believe that there's more choice in filaments than in pellets, since the former has to be made from the latter. Also, a hopper system would make it possible to use materials for support that don't make good filament, like the sugar that Richrap mentions in his blog. 25 kilo minimum order quantities doesn't seem like an insuperable obstacle, considering how much cheaper pellets are than filaments and the quantity of them this proposed monster would go through. Maybe I'll just build it and find out for myself why nobody else seems to have made this work.

Andrew Werby
www.computersculpture.com