Surface Grinder wheel adapter Runout

[Earl Horgeshimer]

What is the acceptable runout on the face of a wheel adapter? I am sorting out my Boyer-Schultz Challenger (6-12). I have 8 or 9 adapters all are left hand except for one. That one was on a wheel that probably was not used on this machine. I wont use that for obvious reasons. I cleaned up all the adapters and with my Mitutoyo tenths indicator, all I see on all but 2 of them is a bit of "noise" when I check the face of the adapter. (less than a half a tenth) One has a thou runout on the face and the other has a thou and a half runout. Looking at them very carefully, I cannot see any dings or scratches on the taper. I spun them in a lathe and cleaned them up with some flitz polish but the runout remained the same. I am sure that the runout is in the adapter and not the spindle. I have a Brown & Sharp 50 millionths indicator that shows just an ever so slight needle wiggle when I rotate the spindle by hand. I have a vfd on the machine so I slowed it down to a couple hundred rpms and the ruby tipped indicator showed no movement at all. So back to the original question. What is the acceptable runout on the face of the wheel adapter?

Thanks,
Earl

 

[Cadillac]

On the face you want as close to zero as possible actually both surfaces should be within a tenth I'd say. But on the diameter surface you can change by truing the wheel. Thinking about it you can true the sides of the wheel also but you do want to start with as low as possible. Not a expert but I'd think a tenth would be okay for a hobbiest.

 

[benmychree]

The right handed adaptor is hot a problem if you have a keyed washer between the wheel and the nut. I have not seen wheel wobble to be much of a problem.

 

[Earl Horgeshimer]

I just looked and there is plain washer on that hub. I will make a keyed one. thank you

 

[projectnut]

I wouldn't be overly concerned with that much runout on the adaptor unless it causes vibration or finish problems. if you measure the hole in the wheel I'm sure you'll find it's at least that much oversize. Once the wheel is mounted it should always be dressed anyway. That should square the wheel to the table and remove any runout on the surface. Many shops dress the wheel every time the grinder is turned on. They want to be sure the wheel hasn't slipped on the adaptor when the motor was started. Slipping on the adaptor (hub) could cause the wheel to be out of balance. Each dressing pass will remove about .001" from the wheel contact surface. In 2 passes the surface on the wheel should be parallel to the table.

If after mounting and dressing the wheel you find there is enough vibration you can feel it, or can see it in the finish on a practice part it's time to either retire the adaptor, or use it for non finish critical parts.