MELB: Checking torque wrench calibration

[King Kenny]

Have 2 relatively cheapo torque wrenches ($100 each - 1/2" & 3/8" drives) that I bought a few years ago. They are both the click/spring type with rotating (worm) collar handle to increase torque settings & have a calibration screw about midway up the wrench.

Am not entirely confident that they are in calibration now after all the use & abuse they’ve gotten over the years. Is there an easy way to check/adjust them or is this an engineering shop job?? I don’t need them to be absolutely perfect – just good enough for home maintenance.

[dazz245]

Just an idea, use weights on the end of you wrench to check the accuracy. Like .98kg on the end of a 2m bar would apply 19.6Nm of turning force (.98 x 10 gives force of 9.8N and the length of the is 2 making the torque 2x9.8).

I can't really illustrate it in words well. You just have to make sure that the bar is horizontal when the bolt stops moving. Uses coins for weights if you don't have any.

[King Kenny]

Thought about doing something similar but reckoned that I’d need to built up some sort of rig/jig to do it right so didn’t go any further due to lack of effort.

Am sure a free spinning bolt through a vertical post with a 0.5m bar welded to it & pin for weights would do the job.

[sir.b]

If you can get your hands on an accurate deflection beam torque wrench, you could always put two nuts on a short piece of threaded rod, grip a wrench in a vice, and then have the wrenches "fight" each other and compare readings...

Justin.

[Quo Vadas]

I think you need them calibrated at an engineering shop. They will also stamp a receipt for you if you still have the books that go with the wrenches.

I have a brand new one if you want it...............all you have to do is fit some new tyres on my bike


d

[sir.b]

About $80 quo..

Justin.

[King Kenny]

Not a bad idea at all Justin! Now who do I know nerdy/anal enough to have a deflection type torque wrench.....

Not really interest in getting anything stamped Quo (or spending money!). Give us a call about your hoops my man...

[Quo Vadas]

^^ Mad.
I'll give you a buzz

d

[vitamine27]

I just calibrate them wi a vice, bucket, and accurately measured water,

specifically at the torque values I'll be measuring, or hi med lo range

[Peter]

Torque a bolt with one wrench, mark it. Torque a bolt with the other, see if it clicks over at the same torque/point. If it's the same then chances are you don't need em re-calibrated:-)