Torque Amp

[MinnesotaDave]

Dave going through a hole as you have drawn will not work as the the crows foot length creates an arc that the drive of the torque wrench needs to be able to move along as the bolt rotates.

You are correct as to it won't work for the normal formula.
But a crows foot would turn as long as there is sufficient "wobble" available in the hole. The handle end of the torque wrench will go up and down though.

[leightrepairs]

So you are saying that this is constructed of the crows foot, then a lever then the torque wrench? This would all be basically in the same plane as each other correct? By extension I envisioned a standard extension that you would use to reach between a ratchet and socket to reach into a hole? If this is the case then no the formula would not apply as there is an additional lever to account for.

[MinnesotaDave]

So you are saying that this is constructed of the crows foot, then a lever then the torque wrench? This would all be basically in the same plane as each other correct? By extension I envisioned a standard extension that you would use to reach between a ratchet and socket to reach into a hole? If this is the case then no the formula would not apply as there is an additional lever to account for.

That is the extension I think William is referring to. A standard socket extension basically through a hole like I've sort of drawn.

Crows foot on the end.

[leightrepairs]

So we are talking about a configuration like this? The carboard represents the bulkhead in your drawing, if this is what we are talking about I am sticking with my statement that it will not work because the extension will travel in an arc.

[ronsii]

Needs a u-joint between the crowsfoot and extension that ought to make it more complicated

[William McCormick]

I'm pretty sure this is the scenario he is suggesting though. With a large enough hole for some "wobble" the system should be able to turn (with a crows foot), but not be accurate using the common formula.

I am saying that by just applying rotational force no lever force through a socket extension, the crow's foot still turns from the rotational force. Meaning that there is no lever force anymore, you get the same power no matter the angle of the torque wrench, the rotational torque makes the crow's foot turn. That is what I want to check out. Because when I put the torque wrench straight out and parallel to the crow's foot, I should still have rotational torque as well as lever force. Now it could be the actuality is that the lever force is all that matters but I cannot see how that is. Where did the rotational force go?

Sincerely,

William McCormick

[ronsii]

I am saying that by just applying rotational force no lever force through a socket extension, the crow's foot still turns from the rotational force. Meaning that there is no lever force anymore, you get the same power no matter the angle of the torque wrench, the rotational torque makes the crow's foot turn. That is what I want to check out. Because when I put the torque wrench straight out and parallel to the crow's foot, I should still have rotational torque as well as lever force. Now it could be the actuality is that the lever force is all that matters but I cannot see how that is. Where did the rotational force go?

Sincerely,

William McCormick

yes... I think rotational force would be fixed and then when the crows foot gets it you simply adjust for the 'crow leverage'... right....

[William McCormick]

If you guys get a chance put a 12" socket extension on a crow's foot and turn it with a ratchet wrench. It is the weirdest movement. It looks like a gear-movement. You have to keep repositioning the head of the ratchet wrench as the crow's foot turns, or else the socket extension would be on an angle. it is a freaky movement you should try it. I do it all the time, I never put a torque wrench to it though, but the more I thought about it, the angle of the ratchet wrench made no difference at all, it could not make a difference because the power is driveshaft power, not lever power.


Sincerely,

William McCormick

[William McCormick]

yes... I think rotational force would be fixed and then when the crows foot gets it you simply adjust for the 'crow leverage'... right....

It is hard to talk about this with sanity. You have to say things like when the 12" socket extension is used between the crows foot and torque wrench you get only the rotational force drive shaft force. But when you do not use the 12" socket extension and put the torque wrench in line and parallel to the crow's foot, with the torque wrench sticking out and away from the crow's foot you should still have rotational force as well as lever force. If the formula is correct I want to figure out how it could be, with both rotational and lever force being applied.

Sincerely,

William McCormick

[ronsii]

I think they still 'basically' cancel each other out..... or add to each other... however you want to look at it

[William McCormick]

I think they still 'basically' cancel each other out..... or add to each other... however you want to look at it

It may be true, I just do not have any way to explain it and I cannot find an explanation here that fulfills my logical side. That is why I ordered the two torque wrenches. This was a topic once 45 years ago in school and the teacher that was teaching about it still had issues of his own but kind of left it like well there is nothing other than trying it yourself or using the formula. Which left me with an empty feeling. And he kept flip-flopping back and forth so I really never took it in as "understood done deal" either way he explained it or felt about it. I cannot remember the rather complex explanation he put forth about it to back up the formula but it was convincing even if he and I weren't convinced without proof. He got into the bowing of the shafts, the angle of forces it was pretty deep and mind altering.

It has been on my bucket list.

Sincerely,

William McCormick

[leightrepairs]

It is hard to talk about this with sanity. You have to say things like when the 12" socket extension is used between the crows foot and torque wrench you get only the rotational force drive shaft force. But when you do not use the 12" socket extension and put the torque wrench in line and parallel to the crow's foot, with the torque wrench sticking out and away from the crow's foot you should still have rotational force as well as lever force. If the formula is correct I want to figure out how it could be, with both rotational and lever force being applied.

Sincerely,

William McCormick

William when you reference an extension are you talking about an extension like in the picture I posted or are you talking about an extension to lengthen to crows foot?

[leightrepairs]

If it is as my picture shows minus the cardboard, then as you change the angle of the crows foot to the centerline of the torque wrench the value does change. When at 0 degrees the value you need to set the torque wrench is lower then the desired torque, as you change the angle the value you set the torque wrench to increases. When you reach 90 degrees the set value and the actual value are equal. The set value continues to increase after you pass 90 degrees. This is all due to the fact that you are changing the length of the lever. I, like you was once unsure of this so I had to do as you are talking about and tested this and found it to be true. If this is what you are questioning I would be happy to replicate this test and take pictures to document, especially if it will save you the money of purchasing torque wrenches just to test.

[William McCormick]

William when you reference an extension are you talking about an extension like in the picture I posted or are you talking about an extension to lengthen to crows foot?

Yes but no cardboard, just your hand to allow you to build torque. If you had a two handle torque wrench it would not cause an imbalance, you would not have to put a hand on it or need the cardboard, and it would not matter which angle you are at with the wrench.

Sincerely,

William McCormick

[ronsii]

Yes but no cardboard, just your hand to allow you to build torque. If you had a two handle torque wrench it would not cause an imbalance, you would not have to put a hand on it or need the cardboard, and it would not matter which angle you are at with the wrench.

Sincerely,

William McCormick

Hmmmmm... do they make a two handed torque wrench???

[ronsii]

I know they make adjustables so you don't have to crowsfoot a regular one when top access is limited...

[leightrepairs]

You can also get a torque wrench with interchangeable wrench bits for it, but this won' help if the extension is needed. Here is an example.

https://www.zoro.com/snap-on-industr...B&gclsrc=aw.ds

[ronsii]

You can also get a torque wrench with interchangeable wrench bits for it, but this won' help if the extension is needed. Here is an example.

https://www.zoro.com/snap-on-industr...B&gclsrc=aw.ds

Yeah, have seen those too... if only I had unlimited money for the tool fund

[leightrepairs]

Well the limit is in effect here also, that is why I use crows feet and a little math.

[12V71]

Hmmmmm... do they make a two handed torque wrench???

Snap On does make "T" handle dial types,

[William McCormick]

Hmmmmm... do they make a two handed torque wrench???

I do not know but a lot is coming back to me about when I learned about it.

If you put a torque wrench on the end of a 4-foot lever and put 556 pounds of torque on it with the wrench, you get 139 pounds of tangential force at the other end of the lever. This makes sense because we know we need 139 pounds of tangential force on the lever at four feet to create 556 pounds of torque on the bolt we want to tighten to 556-foot pounds. So if you were to put 556 foot-pounds of torque alone to the end of a 4-foot crows foot that will create 139 pounds of tangential force, on the end of the lever powered by the torque wrench, and create 556 pounds of torque on the bolt. The lever becomes a one to one torque to torque device. Now with our 1.25-foot torque wrench, we will never see 556-foot pounds of torque while it is outputting 132-foot pounds of torque. However, the lever created by the addition of an inline and parallel torque wrench at 132 pounds creates 139 pounds of lever force upon the end of the four-foot crow's foot. But does not account for the 132-foot pounds of torque above and beyond the lever force it is applying. I would bet that 132/556 which equals 0.2374100 is the amount of over-torque you get. Which comes to 132-foot pounds of added torque. It appears the answer to the formula is also the error in the formula.

William McCormick

[William McCormick]

I do not know but a lot is coming back to me about when I learned about it.

If you put a torque wrench on the end of a 4-foot lever and put 556 pounds of torque on it with the wrench, you get 139 pounds of tangential force at the other end of the lever. This makes sense because we know we need 139 pounds of tangential force on the lever at four feet to create 556 pounds of torque on the bolt we want to tighten to 556-foot pounds. So if you were to put 556 foot-pounds of torque alone to the end of a 4-foot crows foot that will create 139 pounds of tangential force, on the end of the lever powered by the torque wrench, and create 556 pounds of torque on the bolt. The lever becomes a one to one torque to torque device. Now with our 1.25-foot torque wrench, we will never see 556-foot pounds of torque while it is outputting 132-foot pounds of torque. However, the lever created by the addition of an inline and parallel torque wrench at 132 pounds creates 139 pounds of lever force upon the end of the four-foot crow's foot. But does not account for the 132-foot pounds of torque above and beyond the lever force it is applying. I would bet that 132/556 which equals 0.2374100 is the amount of over-torque you get. Which comes to 132-foot pounds of added torque. It appears the answer to the formula is also the error in the formula.

William McCormick

If Dave concurs with my position and can come up with a formula to compensate, I wish to be anointed the mad welding forum torque master, haha.


Sincerely,

William McCormick

[ronsii]

Torque Monster ... oh master

[William McCormick]

I think I got it figured out.

If you take 556 and add 132 to it you get 688 my proposed actual torque on the bolt. if you then divide 556 by 688 you get 0.8081395348837209, that is the ratio I claim the formula is off by. Now if you take 556 divided by 5.25 you get 105.9047619047619048 the amount of tangential force in pounds you need on a single lever 5.25 feet long. If you take 105.9047619047619048 pounds and multiply it by 0.8081395348837209 you get 85.5858250276854928 pounds of force needed from your hand on the 1.25-foot long torque wrench attached inline and parallel to the 4-foot long crow's foot. If you then multiply 85.5858250276854928 by 1.25 you get 106.982281284606866-foot-pounds of torque reading on the torque wrench and applied to the crow's foot.

To check that you multiply 85.5858250276854928 times 5.25 and you get 449.3255813953488383 pounds of pure lever force. Then you add 449.3255813953488383 plus 106.982281284606866 and you get 556.307862679955704 foot pounds of torque applied to the bolt. But I will check this out easily with the two wrenches I have coming. I think they get here Thursday.

Sincerely,

William McCormick

[William McCormick]

I think I got it figured out.

If you take 556 and add 132 to it you get 688 my proposed actual torque on the bolt. if you then divide 556 by 688 you get 0.8081395348837209, that is the ratio I claim the formula is off by. Now if you take 556 divided by 5.25 you get 105.9047619047619048 the amount of tangential force in pounds you need on a single lever 5.25 feet long. If you take 105.9047619047619048 pounds and multiply it by 0.8081395348837209 you get 85.5858250276854928 pounds of force needed from your hand on the 1.25-foot long torque wrench attached inline and parallel to the 4-foot long crow's foot. If you then multiply 85.5858250276854928 by 1.25 you get 106.982281284606866-foot-pounds of torque reading on the torque wrench and applied to the crow's foot.

To check that you multiply 85.5858250276854928 times 5.25 and you get 449.3255813953488383 pounds of pure lever force. Then you add 449.3255813953488383 plus 106.982281284606866 and you get 556.307862679955704 foot pounds of torque applied to the bolt. But I will check this out easily with the two wrenches I have coming. I think they get here Thursday.

Sincerely,

William McCormick

Here is the same thing but instead of 132 that we have been throwing around I used the actual number which is 132.380952380952381 now everything balances out.

If you take 556 and add 132.380952380952381 to it you get 688.380952380952381 my proposed actual torque on the bolt. if you then divide 556 by 688.380952380952381 you get 0.8076923076923077 that is the ratio I claim the formula is off by. Now if you take 556 divided by 5.25 you get 105.9047619047619048 the amount of tangential force in pounds you need on a single lever 5.25 feet long. If you take 105.9047619047619048 pounds and multiply it by 0.8076923076923077 you get 85.538461538461538 pounds of force needed from your hand on the 1.25-foot long torque wrench attached inline and parallel to the 4-foot long crow's foot. If you then multiply 85.538461538461538 by 1.25 you get 106.9230769230769231 foot-pounds of torque reading on the torque wrench and applied to the crow's foot.

To check that you multiply 85.538461538461538 times 5.25 and you get 449.076923076923075 pounds of pure lever force. Then you add 449.076923076923075 plus 106.9230769230769231 and you get 556 foot-pounds of torque applied to the bolt.

But again I will check this out easily with the two wrenches I have coming. I think they get here Thursday.