02-02-2013, 10:41 PM
(02-02-2013, 04:39 PM)DaveH Wrote: That's correct, so the threads sloppy or not don't have a bearing on the ER's concentricity.
Dave, I've been down this road with my carbide grinder trying to get the wheels to run concentric. If the threads in the adapter aren't square to the center line of the lathe spindle when the adapter is tightened down, they can pull the adapter out of alignment. Especially if they are sloppy and have a reduced amount of engagement. You can have more compressive force on one side of the thread than the other, which results in the same pressure difference on the face of the register. Any excess space between the register and the adapter will allow it to move off center.
Brake drum/rotor lathes use a set of self centering washers behind the spindle nut to compensate for this.
Tightening the original sloppy spindle nuts on my grinder caused the wheel hubs to cock sideways by a couple of thousandths. A new set of tighter fitting nuts allowed the hubs to seat squarely on the grinder shaft and eliminate the excess run-out I was getting.
Just my
Willie