With the crank pin so close to the periphery of the crank disc, I found it easier to use slightly oversize stock, drill snd tap for the crankpin and then turn the disc down to diameter. Should I build the engine again, I would probable go for a 2mm hole in the crank disc and make the crankpin shouldered to fit with Loctite - I think that it would be easier to keep the crankpin square to the disc rather than threading. I also reduced the thickness of the crank disc to 2.4 mm as the drawing does not provide for any clearance. Thanks for the series: very helpful.
