Hi everyone - I'm new to Router Forums but wanted to see if someone will give me some needed info. I want to make a circular jig to put on top of a 12" round board that will allow me to leave a 1/8" wide lip on the board, how to I calculate the diameter of the round jig? Like my memory, the formula I once knew is long gone! What I'm attempting to do is make some lazy susans with the lip idea. That should prevent items from falling off the top surface - especially if it should get spun too fast. I would like to use a 1/2" straight bit and corresponding bushing. After routing the circular groove, I'll find a way to remove the rest of the top surface - leaving only the lip sticking up. Help!
No one is ever too old to learn or practice good safety!
