Re: Lying Torque Wrenchs

Posted by humanpotatohybrid On 2023/11/5 20:54:28

To calibrate, simply find some arrangement that lets you torque on the end of the wrench. Easy if you have a welder: simply weld an old socket to a bar. Another one is to jam nuts on a bolt; have the socket on the torque wrench and counter it with a box wrench. Just hold the other wrench and the union of the two to push the torque wrench against a scale. Note the value when it clicks, measure the distance on the torque wrench, and do the math.

In my somewhat brief experience, as long as the torque wrench zeroes properly, it's usually fine. (Adjuster loses all tension when you dial it to zero.) This is because they use Hooke's spring law as the principle of their operation. There are other modes of failure/inaccuracy but they are rarer.

P.S. I should buy one of the digital gauges. I have a HF click type wrench that drifted like 40 lb•ft off within just months.