Storing click torque wrenches(minimum setting)

[tool_fanatic]

I love this board and I'm proud that I am a member now! I'm a very serious DIYer/Mechanic wannabe.

Anyway, I bought some cheap torque wrenches at HF (I know, I know!) but I know someone who can check them and calibrate them when necessary. I bought two 1/4s and 3/8s for $15 and $12 each and they are both spot on, I figured one would not pass. The guy took out a $500 1/4" that someone just bought sent in for checking and the HF had very close performance.

I may keep both (They are worth it even if the end up as breaker bars!) but the guy who checked them said NEVER buy Craftsman torque wrenches because after 90 days Sears will tell you to get lost. He also believes that the HF is better unit if you check/calibrate it! I looked reviews for the Sears Torque Wrenches and they have many complaints. I was going to buy Craftsman but I didn't after he told me that.

He also said even expensive brands like Snap on have some bad apples, and without calibration no brand should be trusted! He also said care plays a big role too. A dropped $500 wrench could be turned into a breaker bar if dropped!

He told me to exercise the wrench at the 20% setting and 80% setting 3X before use. He also told me to store the wrench at 0 torque, but here is the issue...Also, he said get a feel for for various torques, and if you feel the wrench isn't working do not continue tightening!


The HF wrench documentation says to store at the lowest torque setting, and not to go below that. They are 5-80 ft/lbs and 20-200 in/lbs. It says in bold not to go below the lowest number. I did go below that number, close to 0 now I'm wondering if that could damage the mechanism.

What do you guys store your torque wrenches at? Could you damage the wrench by going below the lowest setting (not under 0 though).

Also, I know about quality tools but I'm thinking these are good for my occasional use. Does anyone think that these tools are total garbage and I should wait till I can purchase something better (not craftsman!)?

 

[forceyoda]

All the manuals of my torque wrenches, I have a CDI, an Armstrong, and a proto, say to store at the lowest indicated setting and NOT to go beyond that.

As i understand it, most click style torque wrenches have an internal spring that is compresed as you twist it up to higher ratings. If you go beyond the lowest setting it is possible to stretch the spring and ruin the torque wrench.

 

[TheGrooveking]

As to developing a feel for a given torque that is never a good thing to rely on. Another method is to use a scale, like a fish scale, connect to the handle and pull on the scale to pull on the torque wrench. Now I am not advocating this as method of calibration, but you could use to check to see if the unit is way off. Throw a bolt with a few washers threaded into a nut. Lock the nut in a vise and give it a go with the torque wrench, quick way to see if it is in the neighborhood Mr.Rodgers.

TheGrooveking

 

[tjmonsen5]

my torque wrench starts at 20 ft/lbs. ive always set it to the imaginary 0 when i put it away. looks like ill start leaving it at 20 .

 

[forceyoda]

Here is some usefull info strait from CDI's website-

All mechanical torque wrenches are calibrated from 20% to 100% of full scale, therefore, they should never be used below or above those limits

To determine which torque wrench capacity is best suited for an application, many factors must be considered. However, as a recommendation, use a torque wrench in the middle 50% of the overall capacity of the tool. This will result in longer tool life, ease of use for the operator and increased accuracy from "clicker" type torque wrenches


Always grasp handle firmly in the center of the grip


Approach final torque slowly and evenly


Stop pulling wrench immediately when target torque is reached


Never use a torque wrench to break fasteners loose


Should be cleaned and stored properly


Should always be stored at it’s lowest torque setting


Wrenches should be re-calibrated if dropped. Should never be used in excess of it’s capacity


Torque wrenches should be "exercised" a minimum of three times at 100% of full scale before use


The wrench selected should be calibrated in the same torque units that are specified


Use of a "cheater bar" will result in an inaccurate reading and can possibly damage the wrench


Torque wrenches will last longer if reasonable care is taken. Always unwind handle to the lowest setting after each use. Do not attempt to lubricate the internal torque mechanism. Clean torque wrench by wiping, do not immerse. The wrench should be sent to a qualified calibration lab once every year or every 5000 cycles for re-calibration

 

[tool_fanatic]

Thanks! This is great info and may help others too. Being that I did set it once to under the minimum setting, I will have it rechecked or maybe even exchange it. I did remember reading(wrongly) somewhere that they should be set to zero.

 

[Charles (in GA)]

The ones I've seen apart are not made in any way that you could stretch the spring and damage it if the adjustment is unscrewed too far (springs are compression only, with no hooks or other way to stretch the spring), however, some of the ones I've seen apart, will, if adjusted below the lower limit, allow a block or component of the clicker mechanism to shift out of place, requiring the tool be disassembled to get it repositioned and re calibrated.

Charles

 

[1stwarrior95]

I've alsways stored mine, (C-man BTW! LOL), at the lowest setting. I was just wondering the other day where I could get them calibrated.

Kinda sceptical about that fish scale idea. I'm thinkin that method wouldn't be anywhere near accurate, even to check one out, unless the torque wrench itself is 1 foot long? (1 lb ft requires 1lb of fiorce on a 1foot long lever, correct?) The fish scale wouldn't give a correct reading due to the length of the wrench handle or am I off base? I'd think it would work if you were to compare the fish scale reading on two, (same length), wrenches though.

 

[48548]

I have a snap on split beam and it doesn't matter where you leave it set at, it doesn't do anything to it, and they are supposed to have less moving parts or parts to wear out. I prefer the split beam because the click is really loud and can always hear it.

 

[MXtras]

I was just wondering the other day where I could get them calibrated.

A local instrument calibration service can do this for you. They charge around $25 for a standard 30-250FtLb torque wrench. All you get is a report of what the actual torque is at each torque setting in 5 Lb increments - they will not actually "calibrate" the wrench unless all of the readings are off by a uniform margin. Beyond this, the torque wrench requires repair, not just calibration.

(1 lb ft requires 1lb of fiorce on a 1foot long lever, correct?) The fish scale wouldn't give a correct reading due to the length of the wrench handle or am I off base? I'd think it would work if you were to compare the fish scale reading on two, (same length), wrenches though.

You can do the math on the torque arm length to make the method very accurate. The fish scale method is accurate (perhaps not too practical), but the fish scale itself might not be.

Scott

 

[MrMark]

Good info here!

I am wondering what "exercising" the torque wrench at the highest setting entails. I have never done this and it would be damn near impossible for me to find something to do it on. I never go up near the limit of the torque wrenches I have. What do they want you to do on this?

Is this exercising supposed to happen before every use? Or, is the exercising only when new.

I can almost guarantee that no one is exercising their torque wrenches before they pull them out. I've never even seen it done.

Anyone exercise their torque wrench?

 

[MrMark]

Also, if my torque wrench is from 20-80 nm, I can't use it on 25 nm fasteners? To get above the twenty percent point of the range, the wrench would not be usable until I hit 32 nm? This makes zero sense. I can see that it might not be calibrated to be at its most accurate until it was in the 20-100 percent range, but unusable?

 

[tool_fanatic]

The ones I've seen apart are not made in any way that you could stretch the spring and damage it if the adjustment is unscrewed too far (springs are compression only, with no hooks or other way to stretch the spring), however, some of the ones I've seen apart, will, if adjusted below the lower limit, allow a block or component of the clicker mechanism to shift out of place, requiring the tool be disassembled to get it repositioned and re calibrated.

Charles

Would that make the wrench obviously out of spec?

BTW, the HF wrenches came with a calibration certificate, a table of torque values, with a signature! Says NIST traceable with a serial #.

 

[michael murder]

I had one that said store at minimum setting but needed to be at like 35 lbs. or it wouldn't fit back in it's little case, go figure.

 

[Teikas Dad]

Wow, this thread answered a lot of questions for me. I was wondering about getting a torque wrench recalibrated. Unfortunately I loaned mine to my son and he had it for a year of so where it was left set at a high setting. It's a Craftsman, and I'm kind of curious why Sears won't guarantee them...also, if a spring needs to be replaced to bring it back into spec, who would do that? Sears or an instrument testing place?

 

[crewchief888]

I have a snap on split beam and it doesn't matter where you leave it set at, it doesn't do anything to it, and they are supposed to have less moving parts or parts to wear out. I prefer the split beam because the click is really loud and can always hear it.

i use SO split beam wrenches too. as you said they click LOUD, and you can feel "click".
3/8" and 1/2" dr flex heads, i also have a 3/8"dr micrometer type wrench that goes down to 5ft/lbs that i bought for my honda's when i was racing.

 

[Snappy]

I'd be scared to trust anything that has to do with precision from Horror Freight
The Snap-on guy told me to store mine at a low setting.

 

[1stwarrior95]

A local instrument calibration service can do this for you.

Scott

Hahaha! you obvoiusly live in a more populated area than I! LOL

Thanksfor the info though. I'll check out the cities next time I'm around one!

 

[caper]

By "exercising" I would imagine they mean turning it up to the highest torque and back to the lowest setting before going to the setting your looking for.This would tension and release the spring to make sure it's not sticking.

 

[MrMark]

By "exercising" I would imagine they mean turning it up to the highest torque and back to the lowest setting before going to the setting your looking for.This would tension and release the spring to make sure it's not sticking.

I was wondering if this might be what they mean by "exercising". I can't imagine anyone ever does this. EVER. And they say to do it 3 times!

Is this a bunch of bull or what?

 

[ukvauxtech]

I have a snap on techwrench 1/2dr, and it auto power's off am i meant to turn this down to the minimum torque setting?