Summary This is my third rev of this. Simpler design. I found out I don't need to wrap it around the back. It is tight enough that it holds in place. Plus, you can print it without any support. The original designs were here... http://www.thingiverse.com/thing:790442 It is meant to hold the spool brace holders from http://www.thingiverse.com/thing:705345 This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/8DD9JeCzVbP