Machining the flywheel flanges

Both Flywheel flanges were machined from 3/8 inch thick rounds cut from 7 inch diameter 360 brass bar stock. After milling the three holes in the flange blanks, the blanks were mounted on a mandrel in the lathe and turned to the proper diameter and thickness. The blanks were then returned to the mill and the channels for the spokes were machined. Because the diameter of the flanges were slightly larger than the capacity of the TAIG mill, it was necessary to create a program to mill only half of the flange. Pivoting the blank around the main axle hole and using the crankpin holes as reference points it was possible to machine the flange very accurately in two runs.