One material that I really enjoy milling on the CNC machine, either the Mill One or the LongMill, is plywood. It’s a strong, forgiving material that’s fairly inexpensive, with a decent sheet of 4′ x 8′ sanded 1/2″ plywood costing around $35 to $40 at Home Depot.
The LongMill is designed to handle 2′ x 2′ sheets, specifically because you can take a 4′ x 8′ sheet and get exactly eight pieces from that (minus the cut width of the blade on one or two sides.
I just moved into a new apartment in Downtown Kitchener, and I realized that I didn’t have a shoe rack yet, so I figured that it would be a good project to do on the LongMill as a simple and quick test, and it would also let me get something useful out of it as well.
You can find all the design files and gcode here: https://www.thingiverse.com/thing:3178323
Want to make modifications to the design? Find the Onshape model here: https://cad.onshape.com/documents/a13ff69cba130fe9a7fbe081/w/e8122a12fba4c941c5dcb6f0/e/f80cc298643b4db924d45b1c
Here’s a quick video showing off the milling: