Hello! This instructables will show how to make an inexpensive yet very effective pen holder which will help maintain even pressure across the printing/machining surface of a CNC machine. I was inspired by this instructable by ähöüokul :

https://www.instructables.com/id/Spring-loaded-CNC...

However, I couldn't find the required bits at the time. And so, instead, I searched for an alternative. What I have come up with is an unintentionally steampunk looking, pen holder made from widely available plumbing supplies.

Step 1: Tools & Materials

You'll require only a few fairly basic tools:

Pipe cutter link or you could use a hacksaw
Glue gun

And the materials:

15mm Ø copper pipe
1/2" Brass hex nipple link x 4
1/2" Flanged brass end cap link x 1
1/2" Brass socket link x 4
Duct tape
Two part epoxy
Fine liner pen of your choosing
Spring from a disposable biro

These bits should cost you around £10 and are available from most hardware stores.

Step 2: Assemble

I have made a short video going through the steps I took to build this holder. If you have any questions please leave me a comment and I'll do my best to answer them.

Happy making!