Torque Wrench

[ShadowsPapa]

Unfortunately, I do. Steel rules are subject to misuse and impact which can shorten the rule by as much as a 64th. Tape measures can also require calibration. They are only intended for "guesstimates", and the "calibration" is the amount of slop in the hook. They're built with a slotted rivet to obtain "accurate" inside or outside measurements. The slop should be equal to the thickness of the hook. This slop increases over time as the rivet stretches the slot.
In both cases, they're either right or they're trashed.

I get the tape measure thing - and I have a really nice Starrett tape measure I keep for my most accurate longer than a few inches measuring needs, and my more worn tape measures I use for initial rough cuts or "close enough" measure like height of the truck, for example.

But to me, a steel rule, and what I was taught in machine shop classes, are what's in this picture, second from right. These are the tools my father used when he was chief inspector in the factory he worked in. Taper gauges, multiple steel rules and so on. (and these aren't all that he had - his pockets must have been full some days!)
So, given that these are steel rules, how do you calibrate these?

I have my measuring tools in a metal drawer away from things that can bang or scratch them, or cause them to get bent. I have my originals from HS and college shop classes and later machine shop classes (I'm no expert, but wish I knew more and was better at it than I am)

My "guess" is that taper gauges, if they get worn or dinged, they are trash.
I have more micrometers than I'll ever use! This one is Dad's, and I've got at least 3 decent 0-1" and a number of others I use for measuring crankshafts, pistons and more.

So, these in the second pouch from the right - how would you calibrate these? Not trying to be smart, I really would like to know!
Some of these are not cheapies as his job and the quality of the stuff they made at the plant depended on their accuracy as well as his. He had a lot of Starrett stuff.

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[IamAlan]

I get the tape measure thing - and I have a really nice Starrett tape measure I keep for my most accurate longer than a few inches measuring needs, and my more worn tape measures I use for initial rough cuts or "close enough" measure like height of the truck, for example.

But to me, a steel rule, and what I was taught in machine shop classes, are what's in this picture, second from right. These are the tools my father used when he was chief inspector in the factory he worked in. Taper gauges, multiple steel rules and so on. (and these aren't all that he had - his pockets must have been full some days!)
So, given that these are steel rules, how do you calibrate these?

I have my measuring tools in a metal drawer away from things that can bang or scratch them, or cause them to get bent. I have my originals from HS and college shop classes and later machine shop classes (I'm no expert, but wish I knew more and was better at it than I am)

My "guess" is that taper gauges, if they get worn or dinged, they are trash.
I have more micrometers than I'll ever use! This one is Dad's, and I've got at least 3 decent 0-1" and a number of others I use for measuring crankshafts, pistons and more.

So, these in the second pouch from the right - how would you calibrate these? Not trying to be smart, I really would like to know!
Some of these are not cheapies as his job and the quality of the stuff they made at the plant depended on their accuracy as well as his. He had a lot of Starrett stuff.

That is an impressive array of measuring equipment. As to calibration of steel rules, obviously there is no adjustment that can be made. It's only an accuracy check as measured against a previously calibrated instrument, and an opportunity to make certain they have not been abused.. Go-no go, so to speak. A waste of time? Probably, but then the boss said all instruments were required to be calibrated annually, he meant ALL instruments.

 

[ShadowsPapa]

That is an impressive array of measuring equipment. As to calibration of steel rules, obviously there is no adjustment that can be made. It's only an accuracy check as measured against a previously calibrated instrument, and an opportunity to make certain they have not been abused.. Go-no go, so to speak. A waste of time? Probably, but then the boss said all instruments were required to be calibrated annually, he meant ALL instruments.

Thanks - that's a fraction of what I have. I had a pretty good selection before my father died - I went to clean out his stuff and grabbed all of his good measuring instruments.
I can understand the accuracy check - and if you make a measurement with one tool and then go to another bench or area and use a different one - things can turn south real fast.

 

[Hootbro]

Please tell me how you can compare the two? If you tighten something with one, the second one will not necessarily tell you anything g if the first one was out of calibration and over tightened the bolt.
Testing a torque wrench for proper calibration require more than another torques wrench.

If you have a appropriate sized 8 point socket and a beam style Torque Wrench, you can do a poor mans calibration check of a clicker torque wrench against the beam torque wrench.

I have done this method for years and work fine for anything I am not sending to the moon. Video below shows the basic principle.

 

[ShadowsPapa]

If you have a appropriate sized 8 point socket and a beam style Torque Wrench, you can do a poor mans calibration check of a clicker torque wrench against the beam torque wrench.

I have done this method for years and work fine for anything I am not sending to the moon. Video below shows the basic principle.

I did that test just for kicks. I have a beam type 1/2" drive that goes to 100. Put in a batch of parts to plate, another to strip the zinc off to prep and set up the torque wrench test.
I started with my Proto torque wrench. I set it on clockwise/tighten, set it to 50 and secured it similar to the video and used my Craftsman beam wrench.
I then pulled..... 40, 50, 55, between 55 and 60 finally- CLICK. OK not bad but not great either.
I changed the Proto to counter-clockwise/loosen for most right hand thread fasteners.
Same test - 40, 50, 60, 70........ NO CLICK so I stopped. Ouch. No use going farther - do NOT use this wrench to torque a left hand thread fastener!
Next up - the NAPA torque wrench. I got it from my former boss when he was forced to retire. It says it's calibrated clockwise only. Interesting.
My beam type is older, the scale isn't marked beyond 5 ft/lb points, the 10s are very clearly marked, the 5s in between quite visible as well, shorter lines, so I didn't expect to get closer than 5.
I did the same test on the NAPA wrench and it clicked roughly around the time I saw the pointer on the beam hit 55 - both directions.
I know it's way beyond time to get those calibrated so this has prompted me to do something about it if nothing else.
Is there a date code on any of these?
The Proto has a 7 over 72 on it. It looks about like that era. (7/72)
The NAPA says on the case it's made for NAPA by K-D and has 06 98 above the "Made in USA" on the handle.
If that's the date then my former boss bought it like a couple of years before he quit.

 

[Hootbro]

I did that test just for kicks. I have a beam type 1/2" drive that goes to 100. Put in a batch of parts to plate, another to strip the zinc off to prep and set up the torque wrench test.
I started with my Proto torque wrench. I set it on clockwise/tighten, set it to 50 and secured it similar to the video and used my Craftsman beam wrench.
I then pulled..... 40, 50, 55, between 55 and 60 finally- CLICK. OK not bad but not great either.
I changed the Proto to counter-clockwise/loosen for most right hand thread fasteners.
Same test - 40, 50, 60, 70........ NO CLICK so I stopped. Ouch. No use going farther - do NOT use this wrench to torque a left hand thread fastener!
Next up - the NAPA torque wrench. I got it from my former boss when he was forced to retire. It says it's calibrated clockwise only. Interesting.
My beam type is older, the scale isn't marked beyond 5 ft/lb points, the 10s are very clearly marked, the 5s in between quite visible as well, shorter lines, so I didn't expect to get closer than 5.
I did the same test on the NAPA wrench and it clicked roughly around the time I saw the pointer on the beam hit 55 - both directions.
I know it's way beyond time to get those calibrated so this has prompted me to do something about it if nothing else.
Is there a date code on any of these?
The Proto has a 7 over 72 on it. It looks about like that era. (7/72)
The NAPA says on the case it's made for NAPA by K-D and has 06 98 above the "Made in USA" on the handle.
If that's the date then my former boss bought it like a couple of years before he quit.

Most of those clicker head torque wrenches use a thread torsion bar design and unless stored at the lowest setting for extended storage , go out of calibration quite often because the thread torsion bar inside takes a seat on the tension. That is why I never recommend buying or getting a used clicker torque wrench unless it has a current calibration cert or can be verified at time of purchase.

Also if you decide to send yours in for a "calibration", most precision calibration service companies will actually charge you for two fees. One fee is to actually check the calibration with the second fee to do any repair or adjustment to bring the calibration into spec. You are probably going find both fees will exceed the cost of a new wrench.

 

[ShadowsPapa]

Most of those clicker head torque wrenches use a thread torsion bar design and unless stored at the lowest setting for extended storage , go out of calibration quite off because the thread torsion bar inside takes a seat on the tension. That is why I never recommend buying or getting a used clicker torque wrench unless it has a current calibration cert or can be verified at time of purchase.

Also if you decide to send yours in for a "calibration", most precision calibration service companies will actually charge you for two fees. One fee is to actually check the calibration with the second fee to do any repair or adjustment to bring the calibration into spec. You are probably going find both fees will exceed the cost of a new wrench.

Yeah, I checked the current local fees a few days ago..........
May as well toss the Proto that's so far off and go buy a new torque wrench. The NAPA is pretty good - it's consistent, too. No real problem with that.
I know my boss didn't have it long and it was backed clear off and put back in the case when he was done. It it was from the era where his son worked for him, or even his other employees, I'd question things - a lot. But it was later in his life and just him. And I found it totally relaxed in the case.
Have no idea of the history of the Proto and if those are date codes, that thing is older than many forum members.

 

[jbehrn]

Just swapped out my 3 or 4 year old HF Pittsburg Pro torque wrench under warranty this afternoon, it quit working. The store clerk was impressed that I had kept all the original paper work including the paper box cover. Fortunately the swap was super easy!

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