This is pretty much a guessing guide. If you look closely there is a mark on the dial and on the moving cutter that are supposed to be in line. Best bet is to set and test on a piece of scrap. At 3" setting this is a bear to turn. I have to put all 280 lbs into moving the brace. Using the ratchet to allow 1/4 turns pulling the brace toward my body worked best.
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