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How can aprivate individual (like me) get a torque wrench calibrated?
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Alyn
It depends whether or not you are impressed by bits of paper that say the calibration has been checked. If on the other hand you want to check it for yourself, all you need is to clamp the square drive in a vice so that the wrench lies horizontally, set it to the minimum setting, hang a suitable known weight at a distance measured from the centre of the square drive which will achieve the torque indicated and watch the result. Repeat the exercise for the largest setting. any variation in the settings you have to make to make it click, collapse or read off correctly on a scale obviously indicates inaccuracy. For practical purposes a decent spring balance pulled at right angles to the shaft can replace the weight and a Newton can be taken as a 100 grams
( 0.1 Kg ). Torque = Force (weight in this case) X Distance
What you do about it if it's wrong depends on the make, Britool ones can be adjusted by altering the number of washers on the end of the spring locater, the rest I don't know much about.
Regards
Don Cox
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I usually check my torque wrench myself, using a spring balance. If you apply, say 30 pounds to your wrench via the spring balance, and the wrench is say, one foot long, that is 30 pound feet. A simple calculation will work for any length wrench. If you are worried about the calibration of the spring balance, simply check with a known weight. (1 gallon of water weighs 10lb!)
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thanks all for your answers
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Pete.
That is an imperial gallon..a us gallon is 8lbs..
Now i am not one to split hairs,,,but...
Graeme
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