If you recall, I had a struggle with a Ryobi bench grinder given to me by a well-meaning relative. I first reported the saga in the thread "Vibrating grinder returns" (21 April 2007). The then plan was to machine new end washers to stabilize the stone wheels on the 5/8" arbor shafts.
The Clausing 5914 is now up to the task, and so it was done. Actually, I retained the pressed steel end washers, but used the lathe to face off the center where the nut clamp on the washer. I also machined a pair of
1" OD, 5/8' ID by 1.35" long sleeves of mild steel, to adapt the Norton wheels (1" diameter hole) to the 5/8" diameter arbor shafts.So I put it all together today. The grinder still vibrates badly, with wheels both wobbling side-to-side! But now the reason is obvious; it was not obvious before (because the pressed steel washers were not accurate). The two nuts that hold wheels onto the arbors are crooked, very crooked. The thread axis is not perpendicular to the faces of the nuts, so when one tightens down, the pressure is all on one side of the washer, and so the wheel sways. The deviation is quite large, and easily visible. The left-hand thread nut even looks wrong: the threaded hole is noticeably eccentric in the hex nut outline.
What were they thinking? They have rendered the whole affair almost useless by provision of cheaply made nuts. This has to have saved all of ten cents.
Naturally, the nuts are actually metric, and appear to be M16-2.0, which looks like 5/8-11, but is not. The 5914 lathe does not cut metric threads. Closest it gets is 12 tpi, versus 25.4/2= 12.7 tpi. So I can't just make a set of nuts, my first thought.
My second thought was to re-face the provided nuts. That didn't work either, because the screwthread axis is not parallel to the hex facets of the nuts. So, I gave up.
I will call Ryobi, in the hope that they now have better-made nuts. But I'm close to junking this POS. It's been far too educational.
I was looking at the Delta 8" bench grinder. Amazon offers this unit. Interestingly, there was exactly one customer comment, and that one customer complained of excessive vibration caused by wobbling wheels. Wonder if Delta buys its nuts the same place.
Joe Gwinn