Tell us about yourself!
This is very cool. I built something almost exactly the same a few years ago, but could not figure out the programing and I gave up on it.
Plywood disc with tar paper wrapped around the outside as walls. Rip off the paper, and knock the plywood loose.
I used a plywood base, with tar paper wrapped around the outside, 2" PVC pipe in the middle, steel reinforcement mesh inside, and Pam as a mould release. I also bought the fancy concrete mix with the fiberglass in it to prevent cracking.Works good so far... But needs to be painted.
Before you put the concrete in, already the mould with Pam or some other sort of non stick coating (no joke). They make stuff called mould release, or form oil that they use on construction sites. Also, I hot glued the PVC pipe down first (don't spray the pipe). Just enough to hold it while you pour the cement.