BROACHING THE SUBJECT
When broaching a keyway in a relatively thin part, such as this modified gear cut from a Chevy camshaft or a narrow pulley, I use an aluminum spacer to hold the broach guide bushing up and out of the work piece. This will help hold the broach straighter as it enters the work piece.

Tom Nichols
Automotive Machine & Supply, Inc
Cleburne, TX
May, 2021