How I mill a PCB with a small CNC

Posted by Jim Morris on Thu Aug 18 15:39:50 -0700 2022

This is the procedure I currently use to mill a single sided through hole (not SMD) PCB.

I design the board using eagle, then export the gerber files for the drill and bottom copper, then run flatcam to generate the isolation routing.

I have a smoothieboard with a Smoopi touch screen and MPG pendant attached.

Basically I mount the PCB with a 3d printed PCB holder clamped down to the bed. Then I position the tool at the left front of the PCB, and I usualy use a blunt 30deg engraving bit to probe the bed to generate a grid as the boards are never flat. I use the rectangular grid levelling strategy in Smoothie with the only two corners mode...

G32 R1 X0 Y0 A30 B60

Step by step miling procedure...

Use viewer to set the WCS and check the gcode fits on the PCB.

The flatcam settings I use are as follows (YMMV).

Drilling Procedure....

For drilling in Smoopi I have tool change enabled so I can change the drills as needed.

https://photos.app.goo.gl/XTq92kRHsXREXLEZ7