I'm building the twin compound steam engine (by Bob Middleton) as per the drawings from this site, been wondering about the crank webs, I can do a short cut and cut them straight, but the drawing has a 40mm radius curve on two sides of each web x4. I quite like the design and wondering if anyone has dealt with this before and what they did. I was wondering about a a fly cutter set at 40mm and have each web set in a jig attached to my spindexer. I don't have a vertical mill, but a horizontal one. I have attached a pic of the design.