By having the wrench set horizontally and pulling upwards you are adding weigh of the wrench to the equation. Little error for small wrench but bigger units can add quite a bit and cause false reading. Ideally you would like to pull horizontally. Also remember about "Length Dependency" or "Lever Sensitivity" of click style torque wrenches. You must attach your scale at exact point (usually marked grove on the handle - check manufacture/manual) to maintain true reading.
@@Kslajdbj Fact that you "zero" the scale doesn't mean that you remove the force. Yes horizontal pull would remove the gravitational (weight) force of the wrench handle. However keep in mind all of this fractional and not really applicable to everyday use. Yes if you are a freak and love to mess with it, or you build high precision equipment - use horizontal pull for high-accuracy calibration. But for all other everyday use where +/- 4% accuracy range is expected, it will be easily achievable with whatever pull scale technique you choose. It is more crucial to keep shorter calibration intervals than to mess with superior calibrating technique ;) Average technique calibration every 6 months will be much better than very precise calibration every 12 months ;)
@@ryteulopki8069 Thanks for the reply. I'm learning how to calibrate torque wrench myself because the cost to get it done professionally is about 1/3 of the torque price and I cannot afford that much :(