by KCStudly » Thu Oct 12, 2017 11:00 am
Here's another method you can use if you don't have a big enough torque wrench, but do have a big enough breaker bar.
Measure, in inches, the length of the breaker bar from the center of the socket to the center of where your hand will be; divide by 12. This is the lever arm in feet; for example, my breaker bar measures 16 inches long to the center of the handle, so it is 1.33 ft long.
Divide your desired torque value by the length of you bar. So in my example, if we are looking for a final torque of 80 lbs-ft, then we would want to apply only about 60 lbs force to the handle of the bar (80 lbs-ft / 1.33 ft = 60.15 lbs).
Now get your bathroom scale, put it in front of your wheel and weigh yourself. Set the breaker bar up so the handle is parallel to the ground and so that you will be pushing down to tighten. While standing on the scale push down until the scale reads 60 lbs less than your measured weight. This can be surprisingly accurate so long as you keep the bar more or less parallel to the ground and are able to stay on the scale. If you have to kneel on the scale in order to bend over enough to handle the wrench, then you have to be mindful of the reaction you create and whether you are putting any of the force to the ground through your toes; it might be better to stand on the scale with one foot and press down on the bar with your other foot, just be careful not to fall over and get hurt (disclaimer).
I used this method to good effect when tightening pinion and axle nuts on my Jeep. Those nuts require 175 lbs-ft and I didn’t have a torque wrench that went that high, but still wanted to know that I was getting the right torque.
Last edited by
KCStudly on Tue Oct 17, 2017 2:54 pm, edited 1 time in total.
KC
My Build:
The Poet Creek Express Hybrid Foamie
Poet Creek Or Bust
Engineering the TLAR way - "That Looks About Right"
TnTTT ORIGINAL 200A LANTERN CLUB = "The 200A Gang"Green Lantern Corpsmen