I had an idea on how to get around the problem of drunken threads - a spherical-seat washer, which would allow the wheel to be clamped uniformly despite the cockeyed nuts.
Thew was not space for a fill 5/8" spherical washer set, so I machined a shallow conical seat into the existing flange washers by setting the compound at 14 degrees and advancing by moving the tool slide. The 14 degrees comes from a drawing in the MSC catalog on the washers (MSC #82429366 for instance).
This greatly reduced the vibration, but did not eliminate it. The wheels still wobble visibly.
I knew there was a reason to have a lathe.
Joe Gwinn