If the replacement nuts do solve the wobble problem, there should be no more than the usual problems shared by all grinders. I've ordered new wheel nuts from a local (to Boston) Ryobi service center, Panda Electric. The people at this service center have clearly had things apart, and understood the problem.
Joe Gwinn
Well, the new arbor nuts arrived, and were duly installed. Made no difference - the wheels still wobble badly. Time for diagnosis.
Using a 5/8" ID spring instead of the wheel, holding a flat washer against the underside of the nut, measure wobble with a dial indicator. On one right-hand nut, the wobble wasn't bad, so filed one face of the nut perpendicular to the axis of rotation, to eliminate the wobble.
Tried the same on the left-hand nut. No dice. I would measure, file in the counteracting direction, and on re-measurement the error would increase or decrease, with no obvious pattern. Repeat. This went on for at least an hour of growing frustration before inspiration struck - measure the wobble as a function of how far the nut is screwed onto the arbor.
Bingo. Even plus or minus one thread makes all the difference in the world, varying from no wobble to 0.020" wobble. The arbor thread is drunken! Not visibly, but enough to make the grinder useless for any non-crude purpose. No wonder it seemed random. Reassemble grinder, put tools away.
That grinder was good money after bad. Yet another unsolicited learning experience.
I've written this grinder off, and am in the market for a real bench grinder.
Joe Gwinn
PS. The left and right hand nuts came together in a bag, but so far as I could tell no political arguments broke out.
I have a 8" 1 HP Dayton grinder for sale, old and dirty, on a pedestal, with shields, $30, local pickup only in N. IL, 3 phase.
i
Usually its after the arguments that they get lumped together, for me anyway.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.