One of the principal reasons for purchasing the CNC machine was so that I could make circuit boards. I modified the wall clock ATmega328 design that I used to try Dirty Boards (see previous article). Using the Fritzing PCB board layout software, I added a 5v regulator and some passives, and altered the layout so that all traces were on the bottom side.I also added a copper fill ground plane to minimize the amount of copper that had to be removed. The new design files were then exported in “Extended Gerber” format.
The USB CNC Controller has a 14 pin connector for connection to an external “Jog Controller”. This controller allows the user to move the spindle along each of its three axis, and control the speed at which the movements are made. While there were no instructions for this, a little trial and error established the connections and the necessary circuitry to perform axis movement.
Even though I’m waiting for the 14 pin connectors and big fat momentary switches (on order from China), I made a prototype. It consists of a sloped-top wooden enclosure with an engraved fascia (CNC’ed, of course). I have populated it with LEDs, small momentary switches (which I have previously found to fail intermittently !!) and the jog speed control. The Jog Box connects to the CNC USB Controller with a 14 conductor ribbon cable.