And then I accidentally printed a bust of Yoda out of PLA
While I was in the middle of printing out the parts for my Reprap, I ran out of ABS plastic. Thankfully, in my last order from Ultimachine, they happened to throw in a few loose coils of colored ABS plastic. How nice! Now it was time to finally use them, mostly out of necessity. So I printed a nice motor mount in red:
Then, just for fun, I tried out a print of a super high resolution Yoda bust with a ridiculously small layer height—0.15—lower than I’d ever tried before. To my surprise, though the next print would need a lot of tweaking, it came out better than I had hoped. And the detail in the areas that came out was phenomenal:
Boy, that stuff sure is shiny, huh? Hmmmm… And it seemed to be a lot stickier than the white ABS I’d been using before. Hmm… On a hunch, I pulled the filament out. Tug tug tug. Resistance! After getting it out, here’s what it looked like:
See that bulge at the end of a long skinny part? That’s what PLA looks like when you pull it out. This was PLA. I’d been successfully printing with PLA, and I didn’t even know it!
I have no idea why this suddenly started working after every single prior attempt to print with PLA resulting in failure. And moreover, it started working without me knowing, and without changing any of the software settings to compensate. There are times when technology really does seem like black magic.
In all seriousness, I do have a theory. I tightened the filament drive idler to Schwarzenegger-like grip strength, and I think that helped it bust through jams caused by the PLA expanding too high in the barrel. Never underestimate the power of a strong grip on the filament. Stepper extruders put out a ridiculous amount of torque, and the stronger they grip the filament, the more force they can push it with. I’m convinced that this was the decisive factor. The biggest problem I had in my last few attempts was that the filament inside the barrel was expanding and causing too much friction. I think allowing the extruder motor to push the filament harder gave it enough oomph to overcome whatever friction was caused by the unwanted expansion.
In any event, I’m ecstatic.
Categorised as: 3D printing, Star Wars