Trying To Grind Jaws

Tony Wells said:
I'm not sure they are actually canted. If they are swinging around on the centerline of the spindle they really can't be. Now if they come out tapered, either belled open at the front, or back, they merely grip the stock in that area and the stock hanging out is really unsupported, and not rigid. When you put your indicator on the stock or test bar several inches out, you should be able to "bump" it to where it runs true. If you can't bump it and have it stay where you move it, then the chuck actually is holding by the full jaw length, or a good portion of it. If there then is runout on a piece a few inches out from the chuck that you can't move, definitely there is a jaw problem. But I don't believe that would or could come from grinding.

I'll go ahead and ask the dumb question: You are spinning the chuck under power when you are running the grinder in on the jaws, aren't you? Don't be insulted, please. But it is possible to create the problem you seem to have if you ground the jaws one at a time with the chuck stationary.
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Tony, I do it with the chuck running. The jaws will grip tight and evenly but at an angle. I can rotate the test bar and the high spots are at the same place in the chuck. The master jaws are tight. Right now I have an older Cushman chuck and I went back to it. I had put the 3 jaw Fuerda on and had an old rifle barrel I was going to polish to reblue and when I went to run the tail stock up to the barrel, it was off considerably. I loosened the chuck, rotated the barrel and with the muzzle on a live center retightened the chuck. Started up and the barrel was noticeably out. That's what started all this.
 
yes they are gage blocks, i have all kinds of them ,i used to work for besly and we made fonda blocks
 
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