Introduction: Make Your Own CNC Hold-down Clamps

By Build Awesome

After using a CNC milling machine for a while, you are bound to break, mar, or otherwise ruin your hold-down clamps. Instead of buying more, you can use your CNC to make more!

The design for these is very simple. You'll need some hardware to make them work though:

  1. Clamp material: any kind of wood should do. I used colored MDF to make them colorful.
  2. M5 Hardware: you'll need a couple of M5 bolts, or whatever your wasteboard accepts.
  3. Threaded insert: I used this threaded insert to make the cantilever in the back of the clamp.

You can see the full BOM in this project.

Step 1: Using Easel to Cut Out the Parts

Easel is a combined CAD / CAM / CNC control web app made by Inventables. You can use it to generate gcode and even send your gcode if you are using a shapeoko.

Open this project by going to this page and using the “Open in Easel” button and copy the clamp set project.

I used 3/8" MDF, but you could use any material.

Step 2: Press in the Threaded Inserts

The circle is perfectly sized for the M5 sized threaded inserts with a 6.35mm mounting hole. Just press them into the hole.

Step 3: (optional) Sand Down the Edges

I sanded an angled edge onto my clamps to give them a lower profile for the part of the clamp that is over the material. This makes it easier to avoid hitting the bit against the clamp.