Milling of a printed circuit board
We are currently working on our
[Bad Link] (Mendel). Sadly the control board that we ordered (Generation 6) was broken. Somehow it turned mad whenever we tried to home the printer. Thus we decided to manufacture a control board on our own. We took the layout files of
[Bad Link] and used
[Bad Link] to turn the layout into GCode for a 0.7mm end mill. These preperations were quite easy, but the final step turned out to be rather time-consuming.
This was our attempt with PCB milling, thus we needed to experiment a bit.
For the milling process we prepared a small water basin to keep the plate covered with liquid during the operation. Otherwise we would pollute the air with ugly small particles attacking our lungs. We simply used tape to create this more-or-less waterproof basin. The plate was screwed to the t-slot table via four holes in its corners. Overall the water basin was not very reliable and quite a good amount of water went down into the t-slot table below. The table was made of simple spruce and sucked all the water, albeit its shape was transformed significantly. Luckily the table was quite worn anyway, thus we did not feel sorry about is loss.
We used tiny drills (0.7mm), since the smallest holes in the plate were around this size. But the tiny drills broke too easily. During the milling process we lost three drills, thus we needed to expirement a lot with feedrate and spindle speed. I guess, we learnt that you should prepare a toolpath for all small features of the plate and then run the rest with a bigger tool. This would have saved us a lot of time and probably one or two drills.
But in the end we were very happy with the result: all the features of the PCB look clean and perfect. Hopefully the new board will work better than its predecessor with the Reprap machine …