Got maybe half way through making the crank pieces, need to figure out a good way to attach the sprocket next, since it will be welded inside the crankshaft sides.
Rough cut the flat bar and rod pieces on horizontal bandsaw
For the rod pieces, I then faced off both ends in the lathe, then used height gauge to scribe a witness mark and measure total length. Then when putting piece in the chuck I set it up against the bit and set a dial indicator to 0 and knew exactly how much to take off, got them all within a thousandths (which is very unnecessary)
Tapping the fine thread took way more time than I expected, wasn’t brave enough to try power tapping so it was all just by hand
Drilled the crankshaft holes all at the same time after evening up the ends with an endmill, the holes are exactly 4.160" apart
Showing how the pieces of the crank will go together, the non zinc plated rod will be welded to the sides with the ball bearings already on the shaft. Will probably 3d print a jig to hold the sides when welding to be sure they are as parallel as possible