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Apparently. :rofl:
Torquing Wheel Hub Assembly
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I still assert that a cheater bar should not be used on a beam or click type torque wrench and doing so will affect it's accuracy.
My explanation before may have not been as accurate as I would have liked, I was going off old memory.
The subject came up when I was in the Air Force and a PMEL technician explained the reason why. We also went back to our shop and researched it on the internet and found a source that gave a clear explanation and confirmed it. I cannot find it now.
Just about any beam or click torque wrench manufacturer's instruction manual will tell you this...
"Use of a "cheater bar" will result in an inaccurate reading and can possibly damage the wrench"
"A “cheater bar” should NEVER be used on a torque wrench to
apply excess leverage."
Also...
"As most torque wrenches are length specific, always grasp the torque wrench in the center of the
handle. If two hands need to be used, place one hand on top of the other."
"Always grasp handle firmly in the center of the grip"
If you think about it, if you're pulling from farther away from the pivot point it's easier to pull. So isn't easier for that "click" to occur also?
But they are your bolts so I guess you can believe and do what you want.
I will continue using my calibrated tools as they are intended to be used.
My explanation before may have not been as accurate as I would have liked, I was going off old memory.
The subject came up when I was in the Air Force and a PMEL technician explained the reason why. We also went back to our shop and researched it on the internet and found a source that gave a clear explanation and confirmed it. I cannot find it now.
Just about any beam or click torque wrench manufacturer's instruction manual will tell you this...
"Use of a "cheater bar" will result in an inaccurate reading and can possibly damage the wrench"
"A “cheater bar” should NEVER be used on a torque wrench to
apply excess leverage."
Also...
"As most torque wrenches are length specific, always grasp the torque wrench in the center of the
handle. If two hands need to be used, place one hand on top of the other."
"Always grasp handle firmly in the center of the grip"
If you think about it, if you're pulling from farther away from the pivot point it's easier to pull. So isn't easier for that "click" to occur also?
But they are your bolts so I guess you can believe and do what you want.
I will continue using my calibrated tools as they are intended to be used.
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10,572 Posts
geroux, What you wrote makes no sense.. But if you like it go with it.. But its wrong...
The rotational force at the fastener does not care if you use a 1 foot wrench or a 10foot wrench to reach the load. And the wrench is calibrated for the end with the socket .....
Where you put your hands is your business. But on high load or high torque I am putting them out as far as I can on the wrench. And if need be I am going to put a cheater pipe on it..
And I am done with this as those that can not get it, will not try... And those that do have already said it... So reread what was posted and I am out of here...
The rotational force at the fastener does not care if you use a 1 foot wrench or a 10foot wrench to reach the load. And the wrench is calibrated for the end with the socket .....
Where you put your hands is your business. But on high load or high torque I am putting them out as far as I can on the wrench. And if need be I am going to put a cheater pipe on it..
And I am done with this as those that can not get it, will not try... And those that do have already said it... So reread what was posted and I am out of here...
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1,490 Posts
With a beam type torque wrench you would only be able to cover the pivoting handle and then keep the pivoting handle in the centered neutral position, otherwise the reading would be inaccurate. That would be a difficult task.
You cant slide a breaker bar halfway down a beam type torque wrench and expect any accuracy, they measure by beam deflection.
As for the micrometer type torque wrench I dunno, obviously I see what everyone is saying and can wrap my head around it and there is logic to what you are all saying, but in Geroux's defense the literature included with mic type torque wrenches do say cheater bars affect accuracy.
I'd like to know why.
You cant slide a breaker bar halfway down a beam type torque wrench and expect any accuracy, they measure by beam deflection.
As for the micrometer type torque wrench I dunno, obviously I see what everyone is saying and can wrap my head around it and there is logic to what you are all saying, but in Geroux's defense the literature included with mic type torque wrenches do say cheater bars affect accuracy.
I'd like to know why.
Like I said, it was explained to me by a PMEL technician back in 2006 and was verified by something we found on the internet. Just can't find it right now.
Just trying to help but if no one cares to believe me so be it. It's your bolts.
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That's a reasonable description of what is being applied to the effort of torqueing a fastener with a torque wrench.
I agree with your description...
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I'm not closed minded and maybe there is more to it. I did some searching and can't come to a concrete conclusion that I would be willing to present as fact.
Most of what I find is people on internet forums assuring that you can put a breaker bar on a torque wrench.
The other thing I see is just about every manufacturer of torque wrench's saying using a breaker bar on a torque wrench will affect accuracy.
Maybe it does affect accuracy by a very small margin, maybe an inconsequential margin for our needs...I don't know.
I guess the question is if you want to believe "people on internet forums" or "just about every manufacturer of torque wrench's"?
I believe the latter and the PMEL guy I talked too. As I said, I'll continue using my calibrated tools as they were intended to be used. You can use them how you want. They are your bolts.
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1,490 Posts
This is what Charles in Georgia has to say. I believe this to be accurate.
06-29-2009, 09:57 PM
Several years ago I spent most of a morning at work with the guy who then calibrated all of the hundreds of torque wrenches the airline I work for, owns. One of my arguments was that a micrometer type clicker torque wrench was a rigid tool for all intent and purposes and you could pull anywhere on it and it was still going to click at the proper set torque, just that you would exert more force if you pulled half way down the handle vs pulling on the proper grip. He proved I was wrong. The tubular shaft of the micrometer type torque wrench flexes as you pull on it, and this is built into the calibration of the tool. He demonstrated this to me by taking a 600 lb/ft 3/4 drive Proto clicker and putting it on the calibration equipment. The calibration equipment pulls on the handle just like your hand does, using a very fine thread hand wheel and screw and mechanism. He set to pull near the end of the handgrip, then at the inner most part of the handgrip, then part way down the tube of the torque wrench. What I saw were very different torque readings when it clicked. Even changing where on the grip you pulled, made a difference, but pulling on the shaft of the tool below the grip made a huge difference. We took the torque wrench to a full 600 lb/ft and I was surprised to see that the shaft looked like a banana. Apparently when we are pulling that kind of torque using the tool, it happens so quickly and we just are not watching the torque wrench, I had never noticed before.
This is not to say that all micrometer clicker torque wrenches are like I have described, but you have no way of knowing without experimenting on calibration equipment like I did.
I have a Norbar 3/4 drive "clicker" of a unique design. Its max torque is 1100 lb/ft and it is 60 inches long, but it comes with a special designed "cheater bar" handle extension that locks on to the hand grip and adds an additional two feet to the length.
Charles
06-29-2009, 09:57 PM
Several years ago I spent most of a morning at work with the guy who then calibrated all of the hundreds of torque wrenches the airline I work for, owns. One of my arguments was that a micrometer type clicker torque wrench was a rigid tool for all intent and purposes and you could pull anywhere on it and it was still going to click at the proper set torque, just that you would exert more force if you pulled half way down the handle vs pulling on the proper grip. He proved I was wrong. The tubular shaft of the micrometer type torque wrench flexes as you pull on it, and this is built into the calibration of the tool. He demonstrated this to me by taking a 600 lb/ft 3/4 drive Proto clicker and putting it on the calibration equipment. The calibration equipment pulls on the handle just like your hand does, using a very fine thread hand wheel and screw and mechanism. He set to pull near the end of the handgrip, then at the inner most part of the handgrip, then part way down the tube of the torque wrench. What I saw were very different torque readings when it clicked. Even changing where on the grip you pulled, made a difference, but pulling on the shaft of the tool below the grip made a huge difference. We took the torque wrench to a full 600 lb/ft and I was surprised to see that the shaft looked like a banana. Apparently when we are pulling that kind of torque using the tool, it happens so quickly and we just are not watching the torque wrench, I had never noticed before.
This is not to say that all micrometer clicker torque wrenches are like I have described, but you have no way of knowing without experimenting on calibration equipment like I did.
I have a Norbar 3/4 drive "clicker" of a unique design. Its max torque is 1100 lb/ft and it is 60 inches long, but it comes with a special designed "cheater bar" handle extension that locks on to the hand grip and adds an additional two feet to the length.
Charles
I think I found the reference you refer to in a maintenance manual titled "Aviation Unit Maintenance Manual for 20-mm Automatic Gun Helicopter Armament" which you can find here:
https://books.google.com/books?id=U...ncentric attachments to torque wrench&f=false
Look at page F11 and note that they talk about the point of force and how it matters even to a "click type" torque wrench...
But, also note that all of this is concerned with the effects of adding a non-concentric attachment where the lengths of the attachment and the point of force with reference to the end of the torque wrench matter.
If you are using a "click type" torque wrench without an attachment then the point of force location is not a factor.
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The click type doesn't know how long the handle is and never will. The reaction to the force being exerted takes place in the pivot portion of the head and that will not change with regard to handle length.
The beam style if that is what you are calling the ones with the needle and scale that depend on the bending of the beam to indicate torque will be the same as long as the cheater is only on the handle and not on the portion of the beam that deflects to indicate force.
You could easily prove us wrong with a simple test using two torque wrenches.
Or a weight, a tape measure, and a cheater.We're not talking about using a cheater to achieve a certain torque value, but why would you? We're talking about taking say a 150 ftlb max torque wrench and putting a cheater bar on the end of it and applying 300 or 400 or more pounds of torque on the wrench to remove a nut or bolt. Torque well beyond the range of the wrench. People on this thread have repeatedly stated that this is how they use their torque wrenches, unless I'm reading it wrong. There should be no reason to put a cheater on a torque wrench. If you can't click a 150 ftlb torque wrench without a cheater get your wife to do it for you.
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1,593 Posts
Amen.
+/- Accuracy is pretty important when you're putting heads on a 6.0 power joke. Or a jeep, or whatever. Harbor freight is cool for the DIY guy, but let's not kid ourselves here, if you were using it everyday or even a couple times a week like I do, your opinion of it would change.Jerry Bransford said:
I have a snap on 50-250 half inch, and 10-100 3/8's. Both are great, and I don't trust any other torque wrenches based off of my experiences.
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