Bowden Extruder for 3D printer
June 3:
I should probably fix my tools before this whole project gets too carried away.
A few months ago, my 3D printer’s old extruder finally gave up. After a few tries, I decided it would be best to scrap the whole thing and get something new. That turned out to be SeeMeCNC’s delta printer extruder. When I got it, I was able to rig up a carriage to fit the new extruder head on the part, but it came with some limitations.
When you run PLA through a metal barrel, the heat causes it to stick to the side walls and plug up your system. This is frustrating because it limits the PLA parts to ones that are very small. The solution is to use ABS, but ABS likes to warp when the parts get really big. So, my extruder setup limited me to small parts, whether I liked it or not. That’s where this design comes in. A little 25mm fan blows on the barrel of the extruder and keeps it cool in the zones where the filament is most likely to get stuck.
I couldn’t make this out of PLA right off the bat due to the aforementioned sticking problem. So I had to make it out of ABS first. So, I printed it as well as I could, and ended up having to do a little post processing work because the part warped on me. That gave me an extruder that was good enough to make the actual carriage I wanted. It was a long way around, but sometimes there’s not a better option.
PLA doesn’t like a lot of heat, however, so the
bottom of this carriage will have to be insulated. I jammed some fiberglass insulation in between the hot end and the barrel, and it seems to be working pretty well. It's not a perfect, or permanent solution, but it will get me through the next few projects. If it never fails, I'll consider it an excellent solution. Here's hoping!
P.S. I broke the thermostat that attaches to the side of the barrel when I was reassembling this. I hope I have another one somewhere!