08-17-2004, 01:38 PM
BLINGMW Wrote:John's method sounds legit to me, it'd prob be best to have a pan hanging from a cable (steal one from local supermarket produce section) or something looped over the wrench so you could ensure the center of the weight was at x distance on the handle. You'd probably be able to test the higher end of the scale that way rather than trying to balance 100lbs on top of the handle or having a kid stand on it.
I was thinking some more about it... Would you have to take into account the weight of the torque wrench itself, to insure an accurate measurement? Some googling revealed the the "Federal Standard" is something like "accurate within 4%". So, for setting of 100ft-lbs, anything between 96 - 104 is fine? Surely a heavy duty torque wrench could weight > 4 lbs (although wouldn't accuracy demand an integral to take into account the delta-d along the length of the wrench? - oh boy, calculus!).
However, if you applied a horizontal force to a torque wrench suspended vertically, then the wrench's downward force wouldn't generate any torque (in an axis that matters) against the bolt. So, maybe use a pulley in combination with the hanging pan. Egad, I'm thinking about this way (weigh) too much :roll: