Grinder Wheels

Lol. Round rocks...
I'll admit, aside from the wobble, the wheels grind surprisingly nicely. I like the shoulder bushing idea. I think that is what I will do.
 
No run out on the shaft and negligible run out on that plastic bushing. But I think the issue is with the retaining washers and the fact that they just sit on this lock ring... there isn't actually anything locking it square to the shaft. So I think a bushing with a back plate is necessary.

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I made a bushing and backplate. Just out of aluminum. The shaft is 5/8" but a big 5/8... I drilled and reamed a 5/8" hole but it's like .003" too small and I don't want to pound it on the shaft. So that was hurdle #1. #2 is I made the piece between centers with a dog. I have a live center in the TS but for the spindle I have a convoluted mt2 dead center in an mt3 sleeve. Both are old and very worn and ****ty... the piece turned with a wobble... so that doesn't help either. Gonna need a new better mt3 dead center and just throw away the sleeve as its old and worn and no good now. I suppose I could also just turn the 2" stock in the TS as its only about 8" long now, but I'd rather avoid having to part the piece off in the end.... Soooo, I'll make another attempt later.
That's my update...
 
I have a Princess Auto 8 inch, looks similar. It was always really slow coming up to speed, then one day wouldn't start without me giving it a spin. Decided it was time to replace it, so bought a cheap Canadian Tire one on sale. Was going to the motor rewind shop so thought I'd get him to check the capacitor in the dead grinder, of course it was dead, put the new one in and it starts in a quarter of the time it did before. Now a useful tool.

Greg
 
Ya it's a princess auto grinder. A pro point.
 
I made mine from a soup can I filled with molten aluminum, before I knew to not use so much extruded (pure) aluminum. That's part of the reason for the poor surface finish. That and not knowing nearly enough about bit geometry, feeds & speeds, etc.

Anyway, I chucked the whole chunk (after cutting off the can), faced the end, bored it for my grinder shaft size, turned down the large OD until it looked nice and seemed like a good size, then after marking out the area between what would become the flanges, I hogged away the material in the middle with a general turning bit. I got them down to the correct smaller OD, then used a parting bit to clean up the shoulders, then parted off the outer one, faced the second one to length, then parted it off as well. No centers or complicated workholding needed.
 
I did it between centers because I'm whittling away at this 2" chunk of aluminum I bought a while back. I'm trying not to waste any by cutting off more than I need to chuck.
 
In my experience the bore in those grind wheels is not very accurate. It is probably not a good idea to rely on it and the bushing to align the wheel. A snug fitting bushing is not necessarily desirable. The side stabilizer plates (or back plates) are all important to hold the wheel perpendicular to the shaft and reduce wobble. On one of my grinders it was the poor quality of the nut that was forcing the plate askew.

With a new wheel mounted and held with low tension on the side plates, I would turn it by hand to see how round the wheel is. Sometimes, the wheel can be tapped lightly on the circumference with a wood dowel to reduce run out. Some play in the bushing can be of help here. After that, and tightening the nut, the wheel needs to be dressed to get zero run out on the grinding surface.
 
Ya I agree. This situation is a lot more tricky than any other grinder I've had cause the shaft has no shoulder to rest on. It's just a spring clip... all of the squareness to the shaft is relied upon by the bushing and backplate. How stupid is that?...
I did make one last night but I messed it up. Bored it out .003" too much. And it wobbles. Made a small bushing to fit into the big one, screwed that up too.... was fun
 
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