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So I've ways had this love / hate relationship with click style torque wrenches. I've never really trusted them, especially "cheap" ones.

So I bought a digital torque gauge, which can be used to turn any wrench into a torque wrench and also test torque wrenches.

I set the digital torque gauge to show max torque reached.

Torque wrench #1 set to 35lbs, it clicked at 30lbs max on the digital guage. Retested it 4 times with exact same results.

With the torque wrench set at 40lbs, it clicked at 35lbs on the digital guage. Again repeated 4 times.

On torque wrench #2, set to 35lbs, it didn't click until 51lbs, again repeated 4 times. Which mean if I had used it, I would have over torqued that bolt.

I am sure a higher end torque wrench would yield better results, but cheap ones are for sure all over the map.

I guess I'll be using a regular socket wrench with the digital guage from now on.

You are presuming that the digital is correct?

Hear your Torquemada concern loud and clear, BK. A licensed aero/auto mechanic/machinist pilot friend owned both a micrometer type click torque wrench and drive beam type. A couple years ago I bought a Craftsman micrometer click 3/8" rated 20-100 ft. lb. reasoning that was the most likely range needed at home. It came embossed w/ serial number and test results.

My old unstinting, perfectionist friend taught me to always set such wrenches down to three or four lbs. before putting them away, never leave them stored torqued.

Am sure the Cliff Clavens will weigh in, but have used it several times since.

Like to remind new Packard owners, and that is certainly not you, that part of a complete tune up in the day was checking head and manifold torque engine warm (unless aluminum head) with accurate torque wrench, and not overdoing it. You want the manifold snug per shop manual listing but still able to freely expand and contract.

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It came with it's own certification. I also check it with my buddies known good high end torque wrench and also an ancient beam style wrench. It matched on both of those.

The one that read 51 instead of 35 is currently in the trash can.

At work (power plant) we would have all the click and digital torque wrenches calibrated yearly. In fact, if you look at the paperwork on most torque wrenches, I wouldn't be surprised if they don't recommend yearly calibration. I've got a couple of click wrenches, but trust my old beam torque wrenches more for critical jobs.

I know that the aircraft grease monkeys send them out to be calibrated. They usually ship them. This disturbs my sense of order and what causes problems. I'd prefer to put it in the truck and take it for a ride to someplace local. Talked to a wrench and he said that's not what they do at the airport.

If they get much use or get dropped, they can need to be recalibrated and perhaps cleaned and lubricated. Any precision device that uses springs will probably drift off spec over time, since springs seem to lose tension with time and use.
I always leave my Bonney Tool & Forge clicker type on a very low torque setting to avoid stretching the spring.
A person might make up a simple test rig with a weight and lever. I'd test at about the mid-range of the torque wrench. For instance, a known 40 lb weight at 3 ft would yield 120 ft lbs, 60 ft lbs at 1.5 ft, and so forth. You could test for accuracy and repeatability.

So is the consensus that the older beam type are the most accurate? Or the new digital ones?

I have a HF click type and I don't trust it. I need to replace it with something that I do trust.

-Kevin

Both the torque wrenches that off were both the same model of HF wrench.

Because of the physical properties of steel, the beam style will stay accurate. They are just more of a pain to use.