How To Calibrate A Torque Wrench 

A torque wrench is a highly specialized and powerful tool that reduces the heaviest bolt and nut tightening works to a cinch. The tool has been found to be extremely helpful in mundane struggles with car wheels. The specialized tool requires it to be calibrated at regular intervals. The process is to be done preferably by a trained professional. But we understand that sometimes that is not the way things work.


So, we have worked out a step by step to help understand the process of calibration of a torque wrench yourself. Though it is not a very heavy task, it is sequential. We should emphasize that it is a necessity to calibrate torque wrench, it is a part of caring for the tool. We will elucidate the process that has been called as ‘Weight Calibration’. So let us begin with the guide asunder. 

  • Locate the center  

First things first, you need to place a mark at center once you have located it. The first marked center should be that of its drive. Keep the mark intact for the next step. 

  • Place another mark 

Now locate the place where you will be holding the torque wrench. This place has to be marked. You would thus end up with two marks. The next thing you need to do is measure the distance that prevails between the marks. Keep the measurement handy, you would need it. 

  • Bring in a bench vise 

This tool is going to help you take the first step of calibrating your torque wrench. Place the head of the torque wrench in the vise. It must be taken care that no part touches the jaws of the vise, except for the head. Now proceed with moving the handle of the wrench horizontally. 

  • Now make use of the measurement 

The measurement you kept handy in the second step would prove useful now. It has now to be multiplied by 20 pounds to obtain a value. This value would be called ‘torque’ and it is at this value that your wrench needs to be adjusted. 

  • Get some weights 

You need to suspend a weight from the positions of your two marks. Grab a 20-pound weight and let at dangle near the second mark. 

  • Look out for the clicks 

If you hear a click at the position of the mark, move the weight in the direction leading to the wrench. If no click is observed, proceed to move the 20-pound weight in the direction opposite to that leading to the wrench. This process has to be repeated 2 or more times to locate a position where you do not witness a click. Mark it. 

  • Make another measurement 

Now you need to quantify the distance that separates the clock mark and the square head. This measurement is to be recorded for another proceeding step. 

  • Apply some physics 

The formula now to be used is T1=T2*(d1/d2). T1 would be the applied torque, T2 would be the torque setting, and d1 is the distance obtained in the second step while d2 is the distance found out in the preceding step. 

  • Repeat the process 

Accuracy is attained only when you repeat the entire calculations a few more times, precisely. 

So, there is no apparent need for a professional as long as you know the process. Do it today! 


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