The other day I was tightening my fork triple pinch bolts to 17ft-lbs and I couldn’t help but feel really worried that I was significantly over torquing them. So I started looking into calibration, which professionals can charge up to $60 per wrench to do! Then I came across this video, which uses a handheld luggage scale. Bought one on Amazon, highly rated unit, $12. Yeah not $5. I wanted more reliable accuracy.
Anyway, I tested the scale out today by picking up a 25lb dumbbell; it read 25.2lbs. Good enough for me. Now I don’t have a large enough vice to use the method in the video to check my wrenches, so I just set my wrench to 25ft-lbs, snapped on a 22mm socket, and put it right on the rear axle, which I know is torqued pretty high. Attached the handle of the scale, pulled, and my wrench was easily taking 34lbs to click. Not good at all. I could have been putting 25lbs on the pinch bolts when I only wanted 17lbs. This is a HF 3/8” torque wrench, been dropped dozens of times. So I made some adjustments and now it clicks between 24.5 and 25lbs every time. Got the pinch bolts tightened down to a much more appropriate feeling torque. I will update with further findings on my 1/4” and 1/2” torque wrenches.
Link to the specific scale I bought (I am not an affiliate):