CNC Knot Mandrels

I've had the pleasure of being able to spend a lot of time with the crowd over at Pocket NC, a local Bozeman business that makes the most affordable 5-axis CNC machine on the market (also referred to as the Pocket NC). This summer I hung out at their booth at Maker Faire Bay Area showing off a project of mine that uses their machine. I've been developing knot software for years as a hobby. The software (called the Advanced Grid Maker and Freakin' Sweet Knots), generates instructions for tying knots, 3D models of knots, and since adapting it for use with the Pocket NC, tool paths for engraving knot patterns into wood. Below is a picture of several knot mandrels that I was able to create over Maker Faire weekend last summer.

Knot mandrels created using a Pocket NC.

Generally, a knot mandrel consists of a number of holes drilled into a cylinder so pins can be inserted and a set of separate instructions explain how to weave between the pins. My software has been generating instructions for knot tyers for years, but only recently have I started making my own mandrels. My knot mandrels have the instructions embedded in the tool, which makes tying the knot much quicker and tidier. Here are some examples of knot mandrels:

PVC Knot Mandrel

This is a knot mandrel which can be used to tie a number of different configurations of knots if you acquire separate instructions for tying them.

DIY Cardboard Mandrel

This is a cardboard knot mandrel that I made for a specific knot. On it is a pattern that was generated by my software and printed out.

DIY Pool Noodle Mandrel

Another mandrel that I made using a knot print out generated by my software.

CNC Knot Mandrel

This mandrel has the pattern for a single knot engraved in a mandrel for a certain size. It doesn't offer the flexibility of other mandrels, but for a specific knot, it provides a tidier knot and faster tying times.

The end result after using a knot mandrel, is a completed knot, whether it's for a bracelet, a covering for a sphere or cube, a handle for a knife or tool or something else. Here are some examples:

30 Facet Globe Knot

This is tied using my 30 facet globe knot mandrel.

Dog Toy

This dog toy was tied using a mandrel that I created out of rolled up cardboard and a printout generated by my software.

6-sided Woven Die

This knot was designed using my software, printed out on paper, and folded around a cube so my dad and I could tie the knot around it.

Bracelet

This bracelet was tied using one of my custom mandrels.

Below is a video that shows a 56 facet globe knot being made using the Pocket NC.

In to CNC? Knot tying? Woodworking? Something else? Let me know what you think in the comments below.