Yesterday was spent fabricating 4 more circles for the silo to be built next. Since this was going to take awhile, I started by making a jig on the ground with some sheets of OSB and scrap blocks of framing lumber. After tracing and cutting the plywood arcs, I just laid the pieces down in the jig then glued and screwed them together. This worked quite well, and the finished discs are all within 1/4 inch in roundness. Tomorrow, we start erecting the silo.