I want to use my RepRap to draw ink on bare PCBs for prototype etching (toner transfer has never been good to me). It’s been done, multiple times. When I looked into the projects I could find, I found they all were broken with the current EagleCAD, or generated horrible, basically unusable traces, or involved a dozen steps involving importing and exporting multiple file formats across a half dozen applications, or they didn’t work at all.
I’d never seen the inside of a Gerber file before, and I’m barely competent to look at GCode, but I never let ignorance stop me before! Google has my back.
After a few hours of bashing away, I present a pretty much usable Gerber-to-GCode converter, written in PERL. I implemented the bare minimum of what I needed to print this board, and I haven’t actually tried it with a pen and a PCB yet but it looks usable to me.
I printed this one on paper with a graphite pencil, so the traces are a bit light, and it’s definitely not optimized; a little more work will have it not lifting the pen and putting it right back down in the same place at least. That’s probably as far as I’ll take it.
The board is actually not quite ready to print anyway but this bit is done now. I will post it online somewhere once I get a proven usable board out of it.