Read the manual!
I remember seeing that in the instructions in all three torque wrenches I've had my whole life. I always set them to zero when I'm done.
I also check one against the others to make sure they're all accurate. I've never had to calibrate any of them. Maybe they're all inaccurate by exactly the same amount?
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
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