Torque Wrench Storage

[69XR7]

I was told that I should always dial my click type torque wrench back to it's lowest setting before storing.

I have a Harbor Freight torque wrench that is advertised as 20-150 ft-lbs, but the tool is actually marked starting at 10 ft-lbs

So for storage should I set it to 20 or 10?

 

[Balor]

Store at the lowest advertised torque, in this case 20 lbs. Your torque wrench uses a spring that should stay under tension for it too function properly.

rngr1

 

[Bagherra]

yep!

 

[Spacey_G]

Store at the lowest advertised torque, in this case 20 lbs. Your torque wrench uses a spring that should stay under tension for it too function properly.

rngr1

Why does the spring need to stay under tension to function properly?

 

[Tonyuk]

Springs can either tighten up or relax if they're not kept under a bit of tension over time.

I keep mine at the lowest setting when storing them.

 

[Spacey_G]

A spring that's compressed a lot may relax over time because of creep. That's the reason for lowering the torque wrench setting for storage.

What's the phenomenon that causes a spring to either tighten up or relax if it's not kept under any load? That seems like superstition, but maybe I'm uninformed here.

 

[Bluejoe]

Hello I had one of my 3/8” torque wrenches checked and calibrated thru Snapon. I never zeroed it out and left it at 50ft lbs. I was told it came back as a level one repair off by
1-5 ft lbs. Not sure if thats plus or minus. It appears they replace what looks like a small chip and returnd the original.

 

[6PTsocket]

Why does the spring need to stay under tension to function properly?

My feeling is the spring should be totally unloaded but not so far that the tool falls apart. When the tool was made, they started out with a spring that was under zero tension, installed it and calibrated the tool. I recreate that by taking all tension off the spring. In practice, I suspect that the difference between lowest usable and lowest serting makes little or no difference. Failing to exercise the tool a few times to redistribute the lubricant, after it has sat for a while leads to bigger inaccuries. Some tools only go to the lowest usable setting which is generally 20% of full scale for a spring type clicker.

Sent from my SM-G900V using Tapatalk

 

[tarmy]

Mine all came with clear instructions on how to set for storage...which is at the lowest indicated setting...not totally unloaded...

 

[Fender1325]

Wow mine stays at 100 ft lb for lugnuts it's whole life.....it's probably way out now haha

 

[M_George]

I read that the HF torque adapter can be used to check and calibrate a torque wrench.
https://www.harborfreight.com/12-in-drive-digital-torque-adapter-68283.html

 

[Spacey_G]

My feeling is the spring should be totally unloaded but not so far that the tool falls apart. When the tool was made, they started out with a spring that was under zero tension, installed it and calibrated the tool. I recreate that by taking all tension off the spring. In practice, I suspect that the difference between lowest usable and lowest serting makes little or no difference. Failing to exercise the tool a few times to redistribute the lubricant, after it has sat for a while leads to bigger inaccuries. Some tools only go to the lowest usable setting which is generally 20% of full scale for a spring type clicker.

Sent from my SM-G900V using Tapatalk

This is my feeling too. Instructions that say to store on the lowest setting rather than with the spring totally unloaded are written that way to keep the tool together, not to prevent some inexplicable spring relaxation.

 

[glentre]

Wow! Never even gave it a thought and always put the wrench away at the last setting it was used. From now on, I'll unload the tension as suggested. Makes sense.

Glen

 

[NYBODYMAN]

I always put mine to 0. I have heard many different ways to do it and have yet to hear the correct verified answer.

 

[3baygarage]

At school they taught to zero them out.

 

[pilotmotor]

If your "click type " has a tube shaft where you tig
hten the handle to raise the setting then yes store it at the lowest advertised setting. If it has a small knob on the side , dial and a flat rectangle cross section shaft then it can stay at any setting because its not preloading a spring.

 

[BDT/NWMN]

I have always stored Mine on the lowest setting. PROTO says to store them at 1/3 of the highest rating.. for a 150 foot pound torque wrench, that would be 50.. To think that I have been doing it wrong since 1970, and My 150 foot pound torque wrench is still within two foot pounds in accuracy?? I must be a lucky, ignorant old coot.

 

[BillK]

I have always turned mine out all the way until there is no pressure on the spring. I have 4 different Snap On wrenches and they get sent in every few years to recalibrate. None of them have ever needed a thing.

 

[gearhead1]

The higher the torque value it is set to, the more compression in the spring. The spring can relax when under high compression for a long time, which could cause incorrect torque. This is why it should be set to its lowest setting.
http://www.rockfordspring.com/relaxation-of-springs

The components in the torque wrench may become separated (specifically the pawl from the cam) if it is set below it’s lowest value. The spring has a tiny bit of compression when set to its lowest value. But if you go to zero (below the lowest setting) there’s no guarantee the components line back up when you start increasing the torque value. This is why you should not go below the lowest value.
http://www.srtorque.com/error-proof...may-be-quietly-sabotaging-your-quality-score/

Look at the blue part hitting the body. That’s the click you hear. See how the pawl rocks.
https://www.thoughtco.com/how-to-use-a-torque-wrench-4150394

 

[dnschmidt]

I think about 20% of full scale would be about right. To me people fret too much about this but certainly storing them at high torque could be a problem and storing them below minimum torque I think would be worse as it completely unloads the system. Store them at a low setting and don't worry about it.