After a couple of do-overs, I’ve finished casting the drivers for 622. It has not been a fast process, but at least it works, and I believe it results in a reasonably good wheel.
I really should have remastered the mold before starting, as every wheel needed a little carving to account for overzealous application of CA on the master. I will print the master in place on the mold bed, rather than gluing it down next time. I will also think about how to construct a mold that actively holds the wheel down, rather than relying on gravity.
The last driver was particularly difficult to get seated in the mold, and I wound up having to force it with a C clamp. I couldn’t figure out why it refused to settle until it had finished curing and I removed it from the mold. Then I discovered that the central boss was too high; so that’s something to check next time I’m doing this.
One nice side effect is that I have a little pile of 30- and 33-inch spoked wheel castings. They’re not appropriate for running equipment, but they might look neat in a junk pile.