Proxxon MF70 CNC Conversion
Posted by retromaster on November 2, 2009
Having found a decent solution for the problem of soldermask making, I decided to further improve the quality of my homemade PCBs by having the holes drilled automatically, rather than manually as I have been doing up to now. I own a Proxxon MF70 manual micro-mill that is quite suitable for conversion to CNC (as proven by several examples I’ve seen on the net). The MF70 has a rather limited Y-axis travel (of only 46mm), but this problem can be solved by a little bit of manual intervention, at least in the case of PCB drilling.
So, thinking that it would be rather cool to have a micro-CNC available for my workbench, I started working on it right away. I made a motor mount for the X-axis, as well as a rigid, set-screw type coupling that also serves as a stop to prevent the play of the leadscrew. The motor mount turned out all right but the center hole for the coupling was a little off-center and not perfectly straight. Anyway, I decided to change the design a little (separate the coupling and the stop) and I ordered some new tools that should allow me to make much better quality couplings / stops.
I also built a control board that connects to a PC host through USB and drives the 3 stepper motors. I’ve managed to drive the steppers using the board (and move the x-axis of the MF70) but there are problems with the USB. I’ll make a more detailed post about the control board later.
Anyway, it seems that I got sidetracked once more. Hopefully, I’ll have some quick progress with this new project so that projects like UFE won’t suffer from more delays. Actually, this MF70 CNC project is the sort of project that should prove to be a time saver in the long run.