Checking calibration of a click style torque wrench
 

Hey guys
I currently have a MAC TWM200A torque wrench. It is a click-dial style with a 1/4'' driver. I also have simmilar 3/8'' and 1/2'', but I dont use those as much. Ive read a couple different ways to check the calibration without sending it to a professional. One of them involved putting the driver head into a vice, but im going to be honest I am a little weary of that idea. I know its the same concept as tightening down a bolt, but still.....
Anyways does anyone have a good trick for checking the calibration on these? I believe my most used driver- the 1/4''- may be off a bit and id like to check before winter comes.

Thanks