Darning Loom (Glueless)

A remix of raykindo65's remix of interestor's "darning machine v1"

Raykindo had already done a great job making it easier to print, and I've mainly tried to simplify assembly and maintenance in case a hook breaks.
* The rear cover is now fully integrated into the body. You just slide the hooks right in.
* The front cover flexes to snap on, supporting against the top and bottom of the loom body.
* I've flattened the disc and turned it upside down, enabling supportless printing.
* Added a groove along the back so the rubber band sits better.

I would like to make the work surface convex again at some point, but for now I consider this project done.
The .blend file is included, should you want to make some changes.