Calibrating a torque wrench click type

[Irishman1976]

I bought a Pittsburgh torque wrench....yeah I know....but only for lugs, I do not intend to use it ever on anything precision. It says plus or minus 4 percent, which of course I can live with, but how would I ever have this checked or get this tool recalibrated? Is there anyplace you guys recommend?

 

[justanengineer]

It should go to the same place micrometers, dial indicators, and anything else requiring calibration goes, to a cal shop. If you can give us a city, someone here might tell you where the local one is relevant to you.

 

[Irishman1976]

Thanks...again I know a stupid question. I am relocated in Lansing Michigan but will try to look it up unless somebody here knows right off hand

 

[J.harris]

I wouldn't spend the money on that wrench to get it calibrated, it'd probably cost more than it is worth. Instead just toss that wrench and buy a new one, or buy a quality wrench that isn't a throw away unit.

BTW, new, those wrenches aren't bad and stay pretty well in calibration, many magazines have covered it.

 

[Zeke]

There are a lot of tutorials on the interwebs that show you how to do it with a vise, tape measure and a known weight. To make it easier, get a cheater that will slip over the handle and extend out anywhere past 2 feet to past 4'

Set your torque, hang the weight and measure the distance. Then do the math. You should be able to move the handle so as to line up with the actual torque you produced. Do this at med-low, medium and med-high settings. If they don't all agree, throw it away.

 

[SMKS]

The Pittsburgh torque wrenches are actually generally pretty accurate. Mine is still quite accurate, especially after you cycle it several times.

If you want, you can try one of the DIY tutorials or buy one of the torque adapters from HF or somewhere else and check it.

 

[P_I_Torque]

I've been told many a times, guys can "feel" when a torque wrench is out of calibration. Maybe go with that?

 

[Stuart in MN]

Car Craft magazine recently did a comparison of torque wrenches and found the Harbor Freight model was actually pretty accurate right out of the box. http://www.carcraft.com/techarticles/ccrp_1304_torque_wrench_testing/

 

[jjjrmx5]

I've been told many a times, guys can "feel" when a torque wrench is out of calibration. Maybe go with that?

I got that joke, coming from you.
And I LOL'd.
A lot.

 

[Steinmetz]

Buy one of the electronic torque sensors that are widely available (I believe even HF has one for about $25). They are configured to receive a square drive, and utilize a strain gage bridge for sensing an applied torque. This will give you some degree of comfort that the wrench is not malfunctioning, and is reading approximately correct.

 

[Steinmetz]

I've been told many a times, guys can "feel" when a torque wrench is out of calibration. Maybe go with that?

I guess it depends upon how far out of calibration.

 

[Steinmetz]

It should go to the same place micrometers, dial indicators, and anything else requiring calibration goes, to a cal shop. If you can give us a city, someone here might tell you where the local one is relevant to you.

It's a waste of time and money sending junk into a cal shop.

 

[Mechtech]

Considering that the recommended interval on most torque wrenches was 90 days or 6 months during my time in the AF and that I could make any wrench read whatever I wanted just by the way it was held and applied. I would say that calibrating a occasional use personal wrench to be a waste of time/money and effort.

 

[justanengineer]

It's a waste of time and money sending junk into a cal shop.

I agree wholeheartedly, especially considering the expense, but didnt want to start a flame war about the quality of the OP's wrench.

 

[RKA]

Buy one of the electronic torque sensors that are widely available (I believe even HF has one for about $25). They are configured to receive a square drive, and utilize a strain gage bridge for sensing an applied torque. This will give you some degree of comfort that the wrench is not malfunctioning, and is reading approximately correct.

2nd this. In all likelihood that new wrench works just fine, you just need something to confirm it, and that HF torque adaptor will do just that. I bought one the other week to check a 20 year old craftsman wrench. I did a dozen pulls with the wrench set at 75 ft lbs. All the readings were within 1 ft lb of one another centered around 74 ft lbs on the adapter. I don't care about absolute precision, just repeatability and some reassurance it's where it should be after 20 years. Just for kicks I did the same with my nearly new PI split beam. It had a little more variability with the readings centered around 73 ft lbs according to the torque adapter. That's good enough for my needs.

 

[cmandp]

I bought the 1/2" drive one just last weekend. I opened and tried adjusting about 5 of them in store before I found one that was somewhat smooth or wouldn't freeze up once it got to a certain point. Tried testing it with a Craftsman beam type wrench but it was hard to tell where it clicked; it seemed to be about 5 ft*lb low from 50 - 100 ft*lb. I think I'm going to try using weights a set distance from the square drive axis of rotation next, just because I can.

 

[SMKS]

I bought the 1/2" drive one just last weekend. I opened and tried adjusting about 5 of them in store before I found one that was somewhat smooth or wouldn't freeze up once it got to a certain point.

That's because you need to adjust the bottom nut that locks it during the tightening process. If you are making a big adjustment you'll have to adjust the lock nut partway through the process. At least, that's how mine works.

 

[mr.speaker]

I've never had a problem with my harbor freight torque wrenches. I also have some older beam style craftsman torque wrenches.

I have been calibrating the harbor freight torque wrenches once a year though, dirt cheap at a school local to me


http://www.hotrod.com/how-to/additional-how-to/ccrp-1304-torque-wrench-testing/

 

[Bagherra]

My elbow has a DA Label 80 (points for anybody who knows what that is!)

 

[bmwpowere36m3]

Holy dead thread... if you pay for calibration/checking then the HF is not worth it. Some places won't calibrate it. But if you have access to a calibrated digital checker (strain-type), then go for it. I don't mean the HF one either.

If you have a LOT of time, patience and precision then weights can be used. However their only as good as your measuremtns (weight and distance). Otherwise send them out for ~$50-100 to angle repair or team torque to be checked and/or calibrated if needed every so often.

 

[G_P]

It's a $9.99 torque wrench. It will cost a hell of a lot more than that to have a shop calibrate and certify it.

 

[guy48065]

Some o youse guys miss the point that IF that $9.99 wrench can be adjusted to specs you end up with a $9.99 calibrated wrench that's as good as a $249 calibrated wrench. The cost to cal is the same--so "not worth it" doesn't play into the equation.

CALIBRATION LEVELS THE PLAYING FIELD