Using the Millright CNC machine to make custom printed circuits

Synopsis

This is the anchor for what will probably be a whole series of notes on using the Millright CNC machine. This first posting give some overview info about CNCs.

Basic info about the Millright CNC

The Millright CNC is a Computer Numerical Control machine. It functions much like a 3D printer, except that instead of adding material, it uses a process of cutting away (milling) material. Even much of the architecture and control circuitry is the same as for a 3D printer.

The Millright M3 CNC machine is available as a (relatively) inexpensive kit. I took about 4 days to assemble it, since I didn’t want to rush anything and I didn’t (yet) know what did what, how, or where.

The CNC itself is merely the platform. To do useful work you also need the following:

  1. A cutting device motor in a suitable carrier that bolts to the vertical (Z) assembly. One of the recommended options for this is the DeWalt DWP-11 finish router, which is what I’m using
  2. A “bit” (mill end) that chucks into the cutting motor. These come in many types depending on what you want to cut and what shape you want the cut to be.
  3. A shop vacuum, if you don’t want to end up quickly up to your knees in shavings.
  4. A vortex separator. If you don’t want the shop vacuum’s filters to clog up in 5 minuter or less. I use one that clamps to the top of a generic hardware store paint bucket (5 gallon size).
  5. An easy way to cut power to the CNC and motor. A power distribution strip with an on/off switch will do. A big red panic button is optional.

Cautions

A CNC machine is a lot scarier than a 3D printer. Think of a table saw that not only wants to randomly shred both you and anything you’re working on, but a killer robot that can rapidly strike out in unexpected directions. Think carefully before you set it in motion and make sure you can stop it quickly!

Next up: designing a printed circuit board for CNC milling (coming soon!)