I made a jig with a runner to run in the miter gauge slot, so the jig slides. A stop on the underside of the jig, stops the jig, when the stop hits the front of the table.
With this setup, you put the wood on the jig, and slide the jig and stock, into the blade. When the jig stops, start turning the stock, and cut the circle. If you don't have a sliding jig, you need to start with a section of the stock, which is at the edge of the circle you want to cut.
I made the same type jig for my router table. Works great.