The wheel plan for 622 requires perfect castings. Unfortunately, every attempt so far using my test molds has resulted in large bubbles. These bubbles are not there when I pour the resin, but seem to be forming during the curing process. According to the Smooth-on website, this could be due to humidity, and I should choose a faster-curing resin. I went with their 310, which has a fifteen minute pot life, but perhaps I should have gone shorter. Sadly, I won’t get to the shop to try another product this Saturday, so I guess I have another week of experiments ahead of me.