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Old 23rd November 2020, 08:44   #7
T-Cut
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Rover75 and Mreg Corsa.

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Quote:
Originally Posted by planenut View Post
- - - set the wrench to first, 30, then 40 and 50, using a luggage scale - - - .
How did you calibrate the luggage scale? Calibration against a standard implies that the standard is accurate. That's not so easy in a DIY situation. All you can do is calibrate the tool using first principles, applying a known load at a measured distance to create a calculable moment/torque. Clearly, the load/weight must be 'accurate' as well as the measurement. I reckon a low/medium priced tool that's accurate to within 10% of the indicated value is pretty good. You don't need an NPL certificate for a car tool.


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