What I cannot create, I do not understand.

Just because you've implemented something, doesn't mean you understand it.

RepRap n00b, one month later

I’ve read numerous posts on Boing Boing and elsewhere about cheap 3D printers from both the RepRap project and companies like Makerbot but I never paid a whole lot of attention to them. I usually shy away from electronics projects, and instead have stuffed myself solidly in the “software” pigeonhole. The only hardware projects I’ve ever done are building gaming PCs in high school (nothing fancy like overclocking or watercooling) and working as a bicycle mechanic at a tool co-op (I can disassemble and reassemble a 70s era road bike or a modern track bike, but that’s the limit of my knowledge). Both of those are pretty far from physical computing or electrical engineering though. Last month I ended up digging a little deeper into DIY 3D printing and ended up developing a strong urge to build a RepRap.

In the past I’ve avoided electronics projects mostly due to fear of destroying circuit boards. I kind of regret that attitude, which is not only a bit cowardly but misguided too. After playing with an Arduino and a breadboard I realized that if you’re careful, there’s really plenty of opportunity for the kind of experimentation and tinkering I’m used to in the world of software. And the feedback loop is just as compelling as it is in programming: examine the system, think about the interactions, tinker, watch it light up/spin around/make noise! It’s so much fun, and gives me the same kind of feeling I got when I started programming. Why didn’t I try this stuff earlier!?

Anyway, in the past month I’ve built a RepRap Prusa Mendel. But I’m not printing yet. I’ve got a ways to go. It is basically up and running: after some minor problems with the wiring and electronics this week I was able to test the motors and the heater. My first attempt at a real test print (a small, flat square I made in Google Sketchup) resulted in the extruder just dragging cooled PLA around the bed. I found a few blog posts and a forum thread addressing this issue. Basically the Z axis end stop needs to be lower, so that the extruder is much closer to the surface of the bed. Also, I think the hot end is too hot, as filament extrudes while it is just idling. So, I’ve got work to do.