I am working on another CNC PCB milling test. I have a bunch of different sized vbits and and "end mill" that I want to check the cutting size with. I opened up an Eagle file that I was using a couple of weeks ago and made a copy of it so that I can do some experimenting.

I have new version of the Eagle PCBGcode ULP (v3.6.0.1) that I am trying out. There is always a little bit of tweaking with each new bit until I have the sizes figured out.

I then export the GCode (Mac) and then open it up in another tool called PCBGCode-Wizard. The tool is Windows based so I am running on a XP virtual machine on my Mac. (It will run in Wine on Ubuntu as well.) The Wizard lets me see the cutting tool path, remove unneeded paths, and optimize the tool movements to reduce wasted movement. In this case I am removing the extra pass that separates the the groundplane since it is not a important for this particular test.

PCBGCode Wizard running in an XP virtual machine

I am going to go test a 0.2mm end mill to see how wide the isolation cut is. I will also get a feel for how fragile this bit is and how fast/slow the table movements need to.

The outlines are actually the path that the cutting tool will take. I have trace widths from 0.001" to 0.025" with each 0.005" increment a little longer so that it is easily to see the steps visually.

The shop is warmed up (it is winter time here in Minnesota) and the Ubuntu PC for the CNC is ready to go. Time to head to the shop (aka: attached garage.)

73 de NG0R