How to setup CNC for making dog gears

[Travis Covington]

In the past we have used aluminum vise jaw inserts and machined a counterbore in the two jaws the same size as the gear OD with a few thousandths shim in between the jaws. When the shim is removed, the two machined jaws can then clamp the gear with very little chance of deformation. Centering the hole is done the same way as you would with any piece, but instead of an edge finder on an edge, you use the edge finder in the hole for both the x and y axis'. Or you can use a dial indicator and get the same result.

This year we will be machining our own gears and will probably go about it in the same manner. The only benefit will be the lack of teeth on the gear blanks when we put the dogs in them. We will put teeth on the gears after the pockets are made and case harden/heat treat them.