Small CNC

Safety

Emergency stop (E-stop) cuts power to motors, should be released only when milling is in progress

Debris and broken tool parts my go flying from the spindle. Wear eye protection when E-stop is released!

Operation

Milling machine

Small three axis CNC machine, controlled by PC with LinuxCNC.

Good for PCB Milling!

Motor driver and spindle controller

Normally set to be controlled by PC, but provides manual spindle control.

Also contains the emergency stop.

LinuxCNC controller

PC running LinuxCNC atop RTAI kernel. Provides manual movement control and runs GCode programs.

Spindle cooling

Water needs to flow when spindle is running. Turned on/off via extension plug along with mill and controllers.

Tools, bits, drills

There's a box with a lot of various tools. Few are going to be useful for PCB milling: a sharp cutting tool, a 0.6 mm or 0.8 mm drill and the 3.175 mm sideways drill.

Use 13 mm and 17 mm wrenches to unscrew the tool holder and replace the tool.

Workpiece probing

Probe triggers when there's a conductive path from it to tool/chasis ground. To use it, the workpiece needs to be isolated from tool/chasis ground and have the proble clamped to it.

Tips & Tricks

GCode simulation/preview

You can verify if everything is correct by importing all files to Camotics G-code simulator.

Ideally your board should start at positive X, Y coordinates with lower left corner near X0/Y0.

Useful GCodes

G0 X0 Y0 F100 -- Non-cutting move to X0 Y0 at 100mm/min, Z coordinate stays
G38.2 Z-5 F30 -- Move Z up to -5mm at 30mm/min (slowly) until probe trips

Pictures

Feel free to upload pictures of your finished PCBs and add link(s) to following gallery: