Thread: How do you recalibrate a torque wrench

Snap-on sell a tool for this but like all Snap-on gear, is grossly over-priced due to their pyramid marketing system and the necessary multiple layers of profit. If you were in Brisbane you would take it to Lionel Otto Instruments in Salisbury who does this for a reasonable charge.

if you are happy to be a little bit out. hook it end to end with a known good torque wrench.

if you want it right, take it to a calibration service (yellow pages)

There are a stack of articles on the 'net.

Google it and you will find.

Ther eare recalibration services that go around to workshops.
Yellow Pages?
Regards Philip A

The way we calibrated our touque wrenches in tech was to hang a weight of the wrench at 1 foot from the centre of the square drive with the square drive held in the vice. (ensure wrench is horizontal) The setting is then whatever the weight is in pounds (ft/lbs)

Cheers, Mick.

weld a socket to the bench so that the torwue wrench can hang horizontally and rotate in the vertical plane. Im going to use FtLb's in this example as the last time I did this I was using a torque wrench that was 2 foot long to the center of the handle

get a 50lb weight
measure out 2 feet from the center of the socket

hang the 50lb weight at the 2 foot mark and then adjust the calibration till it clicks at that point with the reading on 100ftlb

torque is effort X distance from rotation if you know both then you can use that as a calibration point.

This also works if you use a spring gauge and have the torque wrench turning in a horizontal plane as opposed to the vertical one.

Remeber that its not reccomended to use any kind of torque wrench in the bottom 1/4 to 1/3 of its working range so if your torque wrench maxes out at 60 ftlb then you dont want to try to calibrate it at the 15 or 20FtLb setting. You should also try for at least 3 preferably 5 confirmation tests across the remainder of the useable range