After all of my experiments with recycling various HDPE scraps, I finally got around to milling a piece on the Shapeoko at BAMspace.
The piece I used was close to 0.5″ thick. I added a thin piece of MDF beneath the piece so I wouldn’t chew up our nice looking hold-down surface…
The milling took quite a while. The first attempt with a different piece did not work out well, partly due to too high of feed rate, and partly due to a piece getting stuck after being cut out. (I can see the appeal of a vacuum table!)
We use GRBL Controller on one of my old Linux laptops to control the Shapeoko.
Did I mention the milling took a long time? It was about 14 passes at 0.04″ per pass to cut through. I used a 1/8″ bit.
The end results were nice. A little rough, but some sanding and a few hits with a blow touch should clean things up just fine.