Topic: Torque specs for Honda wheels

[Accordingly]

but now the original poster knows. Hey, he could have only 70 on them now.   

Oh yeah...you guys have really cleared it up for me 

[No H2O]

So 'hcrv'... you are saying, from industry/professional knowledge, that any solid socket extension (that holds the wrench further out from the wheel, and sits between the socket and the wrench), is NOT going to affect torque settings -- is this right?  It was my first assumption and I am hoping I'm right.

I work in the Electrical Standards labs...right next to the Mechanical Standards labs. I use their equipment to calibrate my torque wrenches.

You are right. Actually, we are right.

A torque is a rotational force. Some force applied 90° to the arm at some distance.

Who cares how long an extension is, as long as it is kept in line with the bolt or nut. And who cares if the extension twists; a bit or a lot. It will not alter the torque. Hell, you could even have a heavy duty spiral wound spring as an extension. A spring with a constant rotational force (torque) on it, has that force throughout the length of the spring...right down to the fastener.

Also, will adding a "breaker bar" to the end of a torque wrench (clicker-type or otherwise) require different settings, or will it simply make achieving the desired torque easier on your arm? IIRC the torquing mechanism in a torque wrench shouldn't be affected by a breaker-bar type extension because its reading the torque at the head of the wrench, not the handle portion, correct?

On a clicker-type, no, it won't change the applied torque. Whatever you set, when it "clicks", you've applied the selected torque. But I wouldn't want to put a crude pipe on the nice knurled handle of my Snap-On torque wrench. Besides, they are designed for the strength of your average person...the length is chosen accordingly. You could grab a clicker half way up the wrench if your name was Arnold. All the action is just short of the head of the clicker-type.

On a beam type, I don't believe you could add a breaker bar (pipe). You need to apply the force 90° to the wrench so that the plastic handle floats on the pivot point. That is how you use them to obtain accurate results, provided it is calibrated.

[dr_spock]

I did a quick test.

I torqued the lug with the 4" extension on until it clicked.

I took the extension off and torqued the lug again.   It clicked immediately.  There was no movement of the lug felt.



(In my Civic owner's manual, it says 80 fl/lb.)

[No H2O]

Steve, we're not even discussing impact guns and those sockets that limit torque.

The same exact principles applies.  That is the only reference I could locate.  You on the other hand provide nothing.

Steve, how do you figure an extension affects torque between a torque wrench and socket? Use some of your high school physics and prove it to me.

Pros don't use impact guns to tighten wheel nuts.

I never suggested that.     Although you're wrong.  Even the most diligent professionals seat the rim on the hub with an air gun and then use the hand wrench.  There are only so many minutes in a day.

Very funny...don't quit your day job.    So the final torque IS applied with a torque wrench. What I said.

Besides, when is the last time most users even had their torque wrench calibrated?

Never and never will.

So whats the point of using it. You can't tell me with any certainty that the torque wrench you are using torques fasteners to the indicated value. How could you, if it hasn't been calibrated.

Now I know why I do all my own maintenance, and plumbing, and wiring, and ...

Lets be clear; a $100 Sears or Crappy Tire clicker 1/2 wheel torquer is the same quality as a $40 Princess Auto or Deals unit.  The only difference is that ppl paid more at the brand stores. They all function, but the accuracy must be suspect and is usually lower than what's indicated.

I agree to an extent. You also cannot make that statement without knowing for sure, although I would tend to question the accuracy of an off shore/cheaper torque wrench. I know I'd never buy one. Ever crank up the handle...talk about a rough thread. I pays my bucks and own three Snap-On units.

You talk about the accuracy of cheaper wrenches, yet you've never had your wrench calibrated. Just becasue you may have a quality torque wrench doesn't nmean it doesn't need calibration. If after a few times, you note it hasn't changed, you can extend the calibration intervals. Calibration costs money...I thought that is what those over-priced hourly rates were for in shops.  

For the others:
Torque wrenches should be stored with no pressure on the spring and in a dry place. They shouldn't be used as a breaker bar by going beyond the click.

[No H2O]

I did a quick test.

I torqued the lug with the 4" extension on until it clicked.

I took the extension off and torqued the lug again.   It clicked immediately.  There was no movement of the lug felt.

Hang on. Not quite.

Preferably, a torque is applied in one motion till the end valve it reached. Yes, you can apply torque in stages, but the last stage should be a difference of say at least 25% of the final value.

If you stop short, say at 75 lbf.ft. on the way up to 80 lbf.ft. and then re-apply torque, it may click leading you to believe you have reached 80 lbf.ft. when in reality, the fastener is torqued to 75 lbf.ft.

When you come to a stop, it takes extra force to overcome static friction...how much will depend on the finish of the threads, the finish under the head of the bolt and adjacent surface.

Did you ever have to push a heavy box or crate along a floor. Didn't you have to give it a good shove to get it going, and once it was going, it was easier to push. Well there is your static versus sliding friction.

[HeliDriver]

Just for the record, I recently had my 7-year-old, $90 Craftsman torque wrench calibrated. I don't know to what tolerance it was tested to, just that it came back with a little sticker saying "Passed - next calibration due 11/08)".

A co-worker recently had his $250 Snap-On wrench calibrated. It failed. Snap-On said it wasn't repairable, and that he was out his $250. Apparently, their fabled lifetime warranty doesn't cover "precision instruments", or some such.

[articsteve]

Steve, how do you figure an extension affects torque between a torque wrench and socket? Use some of your high school physics and prove it to me.

I'm trying to.    My link to the air gun was one.  Others may buy into your BS about working next to a mechanical testing lab as proof that you are correct.  I think it's obvious as one extends the distance between the wrench and the fastener with 3rd party pieces then the torque is going to dissipate to some extent over flexing and slippage. 

 A torque wrench indirectly measures bolt tension. The technique suffers from inaccuracy due to inconsistent friction between the fastener and its mating hole.

The more pieces, the more inaccuracy. 

You talk about the accuracy of cheaper wrenches, yet you've never had your wrench calibrated. Just becasue you may have a quality torque wrench doesn't mean it doesn't need calibration

I have a cheapo wrench.  99.9 % of home users have a cheapo and nobody gets them calibrated and even if they do to what standards.   In others words, cheapo wrenches $100 and down give the home user a ball park value, particularly 1/2 inch units.  For ppl here to say that 80 ft./lbs is really 80ft./lbs at the fastener is internet babble. 

Measuring bolt tension (bolt stretch) is more accurate but most often torque is the only means of measurement possible.

For the others:
Torque wrenches should be stored with no pressure on the spring and in a dry place. They shouldn't be used as a breaker bar by going beyond the click.

For the others:   

For the click type, when not in use, the force acting on the spring should be removed by setting the scale to 20% of full scale in order to maintain the spring's strength. Never set a micrometer style torque wrench to zero as the internal mechanism requires a small amount of tension in order to prevent tool failure due to unwarranted tip block rotation. If a micrometer tool is has been stored with the setting above 20% the tool should be set to 50% of full scale and exercised at least 5 times before being used.

http://en.wikipedia.org/wiki/Torque_wrench

That is called a reference.  Try it sometime to support your assertions.    Working beside some place doesn't qualify with me. 

[articsteve]

I did a quick test.

I torqued the lug with the 4" extension on until it clicked.

I took the extension off and torqued the lug again.   It clicked immediately.  There was no movement of the lug felt.



(In my Civic owner's manual, it says 80 fl/lb.)

Meaningless.   

[No H2O]

Just for the record, I recently had my 7-year-old, $90 Craftsman torque wrench calibrated. I don't know to what tolerance it was tested to, just that it came back with a little sticker saying "Passed - next calibration due 11/08)".

Check with Craftsman and get the specs. Passed? They're not telling you much.

A co-worker recently had his $250 Snap-On wrench calibrated. It failed. Snap-On said it wasn't repairable, and that he was out his $250. Apparently, their fabled lifetime warranty doesn't cover "precision instruments", or some such.

It was obviously abused. And although it failed to meet say 4% of the indicated value, that doesn;t mean it can't be used. As long as it is repeatable (as I mentioned, the most important aspect), who cares what you have to set it to to get what you want. If the cal report says set it to 75 lbf.ft. to get 80 lbf.ft., its still usable with a cal report.

[No H2O]

Measuring bolt tension (bolt stretch) is more accurate but most often torque is the only means of measurement possible.

I know, even better than angle torquing. Care to tell me how to go about it as quickly as using a torque wrench.


"The more pieces, the more inaccuracy".

Care to explain how or what makes it more inaccurate? Tell me how an extension makes it more inaccurate? I'm listening.

[articsteve]

Measuring bolt tension (bolt stretch) is more accurate but most often torque is the only means of measurement possible.

I know, even better than angle torquing. Care to tell me how to go about it as quickly as using a torque wrench.


"The more pieces, the more inaccuracy".

Care to explain how or what makes it more inaccurate? Tell me how an extension makes it more inaccurate? I'm listening.

Measuring bolt tension (bolt stretch) is more accurate but most often torque is the only means of measurement possible.

I know, even better than angle torquing. Care to tell me how to go about it as quickly as using a torque

Never said otherwise.  You took that quote out of context.  I was explaining to the others that don't think when your wrench indicates 80 ft./lbs. it is actually 80 at the fastner.  see my quote below from previous post

In others words, cheapo wrenches $100 and down give the home user a ball park value, particularly 1/2 inch units.  For ppl here to say that 80 ft./lbs is really 80ft./lbs at the fastener is internet babble. 

 "The more pieces, the more inaccuracy".

When you add an extension you add another joint.  That adds more friction.  More friction equals more torque loss at the fastener, not the wrench.

When you add an extension you are changing the angle of rotation.  Not by much, but it does change because of the deflection caused by the slop in the joints. 

when you apply a force at an angle, you don't get the full force in the original direction; it's a (relatively) complicated formula. Keep in mind where you'd be at if you tried to use it at a right angle: the wrench would "click," but none of the torque would be applied to the bolt, at least not in the direction it turns; the force would all be applied perpendicular to the direction the bolt runs, alright, but not in the direction it turns. If you go look the complicated formula up, it's based on the angle; at such-and-such an angle, you get so-and-so percentage of the torque applied to the wrench applied in the direction the bolt turns, and the rest goes in this other perpendicular direction and doesn't go into tightening the bolt.

[articsteve]

Just for the record, I recently had my 7-year-old, $90 Craftsman torque wrench calibrated. I don't know to what tolerance it was tested to, just that it came back with a little sticker saying "Passed - next calibration due 11/08)".

A co-worker recently had his $250 Snap-On wrench calibrated. It failed. Snap-On said it wasn't repairable, and that he was out his $250. Apparently, their fabled lifetime warranty doesn't cover "precision instruments", or some such.

SIRC:

Try this one day when your bored. 

You can have the wrench calibrated now and then, usually expensively, or simply clamp the square drive working end in a vice, have the handle horizontal, and place a weight on a string hanging from the point-of-pressure at the handle (mid-point of handle), and calculate the foot pounds. Carefully done, this is fairly accurate.

[HeliDriver]

Check with Craftsman and get the specs. Passed? They're not telling you much.

Agreed, but it wasn't Craftsman that did the calibration, it was my employer (who did it for free, BTW  ). So I don't actually know how accurate it is, just that it's accurate enough to be used to torque critical fasteners on a helicopter. That's good enough for me & the lug nuts on the Civic.

It was obviously abused. And although it failed to meet say 4% of the indicated value, that doesn;t mean it can't be used. As long as it is repeatable (as I mentioned, the most important aspect), who cares what you have to set it to to get what you want. If the cal report says set it to 75 lbf.ft. to get 80 lbf.ft., its still usable with a cal report.

I don't know the details, just that the wrench didn't meet company standards (and/or couldn't be calibrated to meet company standards). As for abuse, I suppose the wrench could have been dropped or something, but most guys I've known who own expensive tools treat them with care. All the more so when those tools are used to earn your living.

[barrie1]

Any company that can do Torque spec checks on a torque wrench all generally comform to a particular ANSI calibration which is universal in exceptance. My last employer had a tool repair section as we had 100's of air and measurement tools to keep running all the time. The accuracy had to be constant and was kept up on a full time basis. This actually employs around 10 people or so in this office. 

[No H2O]

"The more pieces, the more inaccuracy".

Care to explain how or what makes it more inaccurate? Tell me how an extension makes it more inaccurate? I'm listening.

"The more pieces, the more inaccuracy".

When you add an extension you add another joint.  That adds more friction.  More friction equals more torque loss at the fastener, not the wrench.

When you add an extension you are changing the angle of rotation.  Not by much, but it does change because of the deflection caused by the slop in the joints.

Friction in the joints? What are you talking about? I already mentioned, you could have a coil spring in line with the fastener. How do you think that would affect the torque if kept perfectly "in line" with the axis of the fastener?

And anything I stated implies "in line" with the axis of the bolt of nut. If someone is using a long extension, it doesn't matter how long it is, as long as it is "in line", and the head of the torque wrench is held in place...as anyone would do with anything longer then a short socket on it. If you had a fixed steel plate at the far end of the extension where the torque wrench is that the extension could be fed through that kept the whole set-up in line, that would be the same as having no extension at all.

When you use a crowfoot wrench straight out from the torque wrench, then a calculation must be performed to torque the fastener correctly. That I understand and know.

Anyway Steve, for steel wheels on a street car -10% in torque isn't even worth talking about.

[No H2O]

Check with Craftsman and get the specs. Passed? They're not telling you much.

Agreed, but it wasn't Craftsman that did the calibration, it was my employer (who did it for free, BTW  ). So I don't actually know how accurate it is, just that it's accurate enough to be used to torque critical fasteners on a helicopter. That's good enough for me & the lug nuts on the Civic.

When a cal report states "Passed", then it means for the given make and model of torque wrench which has published accuracies.

[articsteve]

as long as it is "in line",

That's just it, they never are and never can be held "in line" because of the slop in the joints.  When one adds the third piece (the extension) it tilts one way or the other, but is never "in-line".

Anyway Steve, for steel wheels on a street car -10% in torque isn't even worth talking about

No argument from me on that provided one has compensated.