More work on the flywheel today. First, I turned off the protruding section of the bush that I glued in last night with 'Interseals Loctite', and turned down the boss to make it a bit smaller.
Next, a flat was milled on the shaft to provide a positive location for a grub screw, and the conical end of an M4 grub screw was ground off (using my new vintage hand vice for the first time
) to form a flat end to bear against the flat on the shaft. This did not add any appreciable wobble and the wheel feels rock solid on the shaft.
The flywheel and shaft assembly was held in the lathe with an ER-32 collet chuck in the headstock and a live centre at the other end:
The turning commenced with some chatter at first, but this reduced with the diameter, which I turned down to 55mm. This is 5mm wider than the plans call for, because the original by Steve is a solid disc, whereas mine has some detailing which removes mass, the extra diameter being intended to compensate for this.
The outer aspect and sides of the rim posed few problems and soon ran true, but the recesses were tricky and there was a slight wobble on the inner rim on each side. This is where 'wet and dry' sandpaper and a spot of cutting oil came into their own. I worked away at the recesses for quite some time with this and it occurred to me how valuable an adjunct to turning tools abrasives are. There are still a couple of marks which run out of true and I may go back and fix these later but overall the wheel is good and as far as I can see the wheel and shaft assembly is sound and runs true. My intention is to never take the flywheel off the shaft again unless I have to.
Next, over to the mill and rotary table dividing setup to make a six-hole pitch circle:
... and the flywheel / shaft assembly more or less complete (with bearing):
At this stage I'm quite happy with It. Both ends of the shaft will be shortened but the end you can see will be left sticking out a bit because I've a notion of putting a pulley on it...
I also honed the cylinder this evening, using two 12mm 'Flex-Hones' (120 grit then 240). These are imported from the USA and not easy to find here. They're damn expensive but I just decided to go for it instead of the split dowel method as sometimes time is more valuable than money. They left the recommended cross-hatched pattern on the inside of the cylinder. No photos of this, as they were all blurry.
