CNC Mill

This page is all about the CNC machine I've been building. After starting a project a while back that required building a PCB (HALE on the sidebar- still incomplete), it quickly became evident that drilling holes for through-hole components would be a huge pain. I decided that building a CNC machine to do that (and lots of other stuff) for me would be a better solution.

My single biggest requirement is precision- the initial goal was to mill fine-pitched PCBs, after all. Feature creep quickly set in, however, and now it will not only mill (and drill) PCBs, but also aluminum and, if brief tests are to be believed, steel.

The mill has been through more iterations than I care to think about. It started out with an old Dremel for a spindle and drawer slides as bearings, with an old Pentium-IV PC driving the thing through a cheapo stepper driver board. Eventually all of these things got replaced due to lack of precision. Now all three axes have linear rails, the steppers are driven by high-quality Gecko Drive drivers, and the controlling computer is a BeagleBone Black with a real-time unit to ensure precise motion. The spindle has been replaced twice, and is currently a liquid-cooled, VFD-driven 1.5 kW monster that's way overkill for PCBs, but works wonders for milling aluminum.

A quick before-and-after*:

Before (left) and after (right). The "after" shot has new (and new-new, and new-new-new)... well, everything, with the exception of the steppers.

*"after" being "more recent"; things keep changing, after all.