I used to zero mine, but some of them have instructions to put them at 10 percent of the range (usually like 16 ft lbs), so I do that now.
Oh and one thing I forgot to add in my first post, a good rail (Beam as Brian correctly called it) wrench is a good backup checker for checking the clickers on a test.
Remember my version of english may be different from yours so your name for a tool may be correct in your part of the world and mine correct for me :bigsmiley12:
Brian