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Belair-o
11-17-2019, 06:54 AM
I wonder about the calibration on my Craftsman torque wrenches. Where would one be able to get the calibration checked? Inquiring minds want to know.:)
Thanks, Doug

55 Rescue Dog
11-17-2019, 09:06 AM
I had my Craftsman 1/2in digi-torque wrench calibrated, and it was junk after that. The rubber handle they had to take off to calibrate it wouldn't stay in place, which threw the little window off the scale. I now use it for a ratcheting breaker bar. Replaced it with a Precision Instruments split-beam that works much better. Just had it calibrated for the 2nd time in 12 years and it needed no adjustments. Wasted another 50 bucks to find that out. I have compared my wrenches to my digital inline torque meter adapters for piece of mind.

Belair-o
11-18-2019, 06:04 AM
Thanks for the reply.
$50 to get the calibration done = a decent way along to cost of just replacing wrench. But then, is a new wrench accurate?
Thanks, Doug

NickP
11-18-2019, 08:34 AM
Calibrate it yourself. https://www.wikihow.com/Calibrate-a-Torque-Wrench

NickP
11-18-2019, 08:46 AM
I have compared my wrenches to my digital inline torque meter adapters for piece of mind.

So, how do you know the digital unit is correct? Without a calibrated standard and proper test method approved by the manufacturer one never knows. And yes, for those that will comment on my previous post regarding this, the home method of checking it has flaws.

To add, what is required by the operation of torqueing a fastener? +/- how much? If your home test yields a value within that requirement then torque away. There is another function of proper torque and the application of said amount being performed, i.e. method but I'll leave that one alone for those much smarter than I. I know that will be covered quite soon. Won't it.

BamaNomad
11-18-2019, 09:47 AM
Torque is just 'force x moment arm', so it would not be difficult to rig up a 'test fixture' to test your torque wrench at a few select torque points. (One example is the prior Nick reference).

As for me, I have my 50 yr old beam type Craftsman torque wrench that I pull out to verify the 'clicker' type torque wrenches each time I begin an engine build (every few years). That's about the only times I actually use a torque wrench, as my 'feel' for torque is very good... or at least 'good enough'.. :)