Axle diameter for rear wheel
The way I read your original question, you want to pass an axle thru the rear wheel so can spin it and polish it. I jusy measured my spare rear wheel. I could not get my verniers lined up, so I started dropping sockets into the hole. A 0.938 passes thru with very little play. A 0.944 jams in the hole ant will not pass thru. Since the diameter of this hole is not critical to the operation or fitment of the rear wheel, its diameter may vary noticeably from wheel to wheel. Just my opinion.
Personally, I wouldn't use an exact fit axle, but instead would use cones locked to a shaft with set screws, much like the set up sold for wheel balancing.
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