How to Locate the Center of a Hole With an Edge Finder

[ltlvt]

Thanks Willie. I am not trying to bore the hand wheel I am trying to re bore the hole in the side of the apron . I have got a pretty good idea of how to clamp it to the table what I am asking is if the hole to be rebored is not round how should I go about finding the center. The opposite of the apron has a plug similar to a freeze plug in and engine block to remove the shaft from the back side. I will be taking that plug out in order to disassemble it. But that hole is about 1 1/2 " ID where the shaft itself is only about 3/4" diameter. Thanks again for the reply.
I will try to take some pictures tomorrow.