CNC Machine V2 with RepRap Controller
November 21, 2010
I finally finished my Fireball V90 CNC build. In May, I got the frame, and I planned to use the motors and electronics I purchased for upgrading the Valkyrie-clone CNC. So I made some NEMA-17 to NEMA-23 adapter plates from CD-R disks, and got it all up and running. It's running off 12V for now, with 24V planned in the future.
I use the latest Arduino version of the RepRap CNC controller, minus all the thermal controls (I don't have a thermoplastic extruder). To send the GCODE, I still use Chris Meighan's "GCODE for RepRap" Java program.
22 Nov 2010 -- I had some problems surfacing the table -- the Dremel prefers to cut the material when it is to the left of the cutting direction. In the other direction, the bit tries to vibrate itself loose (and often succeeds). Perhaps as a result of my bungled surfacing, the PCBs were not flat enough to etch properly -- I had to choose between not cutting through the copper, or going so deep that it erased the traces. I've re-surfaced the table and plan to see whether I can get my SOIC-16 IC's and SOT-23 MOSFETs traced. I'm very happy with the accuracy, it's just the cutting bit that I'm unhappy with. A proper PCB spindle and good bits are on my Christmas list this year. For now though, I'm just praying to the gods of sharp steel and static coefficients of friction that my remaining bits stay sharp enough to slice through copper, and that the boards stick to the table. Update: The surfacing did a good job of removing most of the gradient on the table. The V-shaped etching bit is still VERY sensitive to small gradients, and I have enough tilt that the boards are not fabbing correctly, but the results are much better than before. I think I'll get a SOIC if I keep all the small traces in one area. I have that much more respect for LPKF now that I've seen how difficult it is to make a good board.