The wheel requires bearings, stop collars, washers and the steel axle rod. The rod was acquired at the local hardware store and the rest were ebay purchases. In fact, the bearings were offered as replacement roller-blade bearings. I reckon that if eight of them can take the weight of a person, four of them can handle the wheel. I inserted two on each side of the wheel. This might be over-kill, but it should ease rotation and prolong the life of the bearings.
As for the rod – the 5/8 ID bearings did not want to quite fit onto the 5/8 rod. After a little panic, I pulled out a file and spent thirty minutes filing around the rod to allow the bearings to fit (and trying to keep the rod cylindrical!). Luckily it worked, and the rest of the wheel preparation went somewhat to plan…
I found the center of the flywheel using the trammel points and bored a hole just deep enough for the first two bearings to nest into. I then bored a 11/16 hole through the rest of the wheel trying my best to keep it perpendicular to the wheel’s face. The hole is over-sized relative to the axle on Underhill’s suggestion: you can then put the steel rod through the hole and make sure it is perpendicular to the second side of the wheel. Then you can draw around the location of the second set of bearings and chisel out the hole. Ta daaa!
Making the flywheel was pretty time consuming (my efficiency at planing has a long way to go) and so I didn’t want to mess up the hole and have to start over! But it turned out ok and is now ready for mounting onto the frame.