I'm working on a sharft that I turned between centers. All the critical places on the shaft dead on size, as close as I can measure, (.0001").
I now need to chuck this piece in a 4 jaw as close to perfect as I can get it.
Within a few minutes I can get to .001" TIR, and in another few I can get to about .0005" TIR, but no matter how long I fiddle, I don't seem to be able to get it better than that. I have a large collection of dial indicators so I've tried several but they all give the same result. The result is the same turning the chuck by hand or power.
My equipment is cheap, (Shoptask and stock 4jaw). At first I thought there might be that much play in the spindle bearings, but after each adjustment the results remain constant,i.e. if the high spot is at #3 jaw it stays there until I try again.
So my question is; can I get it better or is this the best I should expect? I can't imagine there are any tricks to centering, but are there?
Thanks for all ideas,
Jerry