In looking around the workshop for something to make an egg stand out of (for better photos) I came across some scrap PVC pipe from when I constructed a backdrop stand, and realized that the pipe was round, and white, and might actually work in the Egg-Bot… you know, instead of an egg.
I did a quick test, and it ended up working. The first plot depended on a lot of curves, and since I didn’t bother to spend much time doing a proper set-up (you know, finding the center, adjusting the headstock, tailstock, and distal arm) it wasn’t spectacular, but it did work.
Since the pipe is not a sphere, I did make some adjustments to the SVG file, making sure it wasn’t too tall so the pen wouldn’t angle itself too much. After drawing on the first pipe I ended up wrapping a piece of paper around the second one so I could keep testing without running out of pipes. I also ended up sticking corks into the end of the PVC instead of using cardboard shims. This probably helped a bit with the centering.
I’d like to try to get some thicker PVC, closer to the width of an egg, and keep experimenting with this… it’s a nice way of testing without running through a dozen eggs in an evening.