Using the Shark to find the center of a circle

[BillK]

This is a simple method to find the center of a circle which I used recently. Your Shark is also an accurate coordinate measuring machine.

Clamp your circular part down to your table. Jog anywhere on the left side of the circle, use a bit with a nice point (I use a 60 deg V bit) and set X zero when you have the point aligned with the edge. Jog in X direction only to the right until the point lines up with the right edge. Take the X distance shown and divide it in two, then jog to the left in X. For example, if you get 5 jog over until you are at 2.5 X.

Leaving X where it is, jog forward and align the front edge, set Y zero. Jog in Y only to the back edge and align the point. Take that reading, which is the true diameter, divide it in half and jog back to that number. You are now in the center of the circle, probably within a few thousandths of an inch. If you don't have a center finder that you can mark the center with, this works great.