I don't know if this is "runout", but my 4-jaw chuck doesn't hold stock straight. When stock is centered at the jaws, it isn't centered away from the jaws . It's eccentric.
It took a piece of 1" round and checked it between centers for straight and centered. I then chucked it to within .001 at the jaw ends. 3 1/2" away it was .035 eccentric!
This means that the jaw faces aren't parallel to the spindle, right? Is there anything that I can do to fix it?
TIA, Bob
BTW - I checked the face of the check, to see if it wasn't seated on the spindle right. It indicated +-.001 (6" chuck).