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Re: Torque Amp

MAC, thanks to you I've learned that remembering the formula isn't necessary. Again, multiply the displayed torque times the length (5.25') multiplied times 0.8. Somewhere back in this post you did some math showing 0.8xxxxxx. I don't know how you came up with it but it works.

When I needed this torque amp, I needed close to 600 lbs of torque. As I mentioned, I broke my previous tool using at max of 150 ft/lbs so backed the replacement off to near mid range witch was 132ft/lbs. I did the math and got around 556ft/lbs. I then increased the rotational force a couple degrees ( tangenital haha) to get in the ballpark of 600 ft/lbs needed. In the original post I said I forgot the math and said I used 100 ft/lbs but as I said I forgot the math. All that was important to me was the 556ft/lbs.

Tool length of extension plus torque tool times 0.8 provides a good approximate torque.

5.25 feet times 132.38 ft/lbs times 0.80 = 556 ft/lbs.

Re: Torque Amp

It is funny but the original poster's example shows that he should have 139 pounds of tangential force on the four-foot extension to turn it. The 50-year-old formula converts it into a single lever equation and says that you only need approximately 105 pounds on the torque wrench handle if it was a single lever 5.25 feet long. And then just calculates that the torque wrench will read 132 approximately to get that 139 pounds of tangential force at that 4-foot point on the 5.25-foot lever. It throws out any rotational torque applied at the joint. Which we know the rotational force is a one to one force.

Sincerely,

Wiliam McCormick

Re: Torque Amp

Originally Posted by farmersammm

I know I'm late to the party, and math isn't my strong suit.........

Attachment 1719956

Without comparing the torque wrench reading to a known standard, I don't see how you can extrapolate a linear relationship between the straight line force applied to the torque wrench, and the actual torque applied to the fastener. The torque wrench depends on deflection between the handle, and the fastener(the middle of your joined wrenches).

You can apply force to a lever to create torque, then take that torque and convert it into straight line force.......................gears. But the direction changes at the point of conversion

For some duration of time, and amplitude of force...............the torque wrench head is soaking up energy before it transfers your pull on the handle. It's attempting to rotate its head in the opposite direction of the direction you actually want the force applied. You're essentially working with a spring loaded hinge.

I just don't see how you can read that torque wrench with any degree of certainty. Anyways.........the shop ought to be warm by now, and my noodle is getting tired

For a week in math class back in the day when you just didn't run out and by a couple of torque wrenches we had this on the chalkboard. And every day we looked at all the forces and came to the conclusion that if you used a socket extension into a crow's foot from the torque wrench it becomes a one-to-one torque reading to the torque applied to the bolt. So without a torque wrench or a scale or two torque wrenches to test with, we could not swallow that the rotational force the reading on the torque wrench could be dismissed. The lever-action created by the added lever length of torque wrench when it was in line with the crow's foot and not separated by a 12" socket extension would seem to have to compound or add to the total torque applied to the bolt. I have still not been able to build anything because I really do not want to waste material and time just to get a larger mystery. I can say from just fiddling that there is a difference from the standard 50-year-old formula but not as much of a difference as I suspected and tried to calculate for. I have to finish a root canal today so I probably will not get around to it. But from fiddling first with no crow's foot, both wrenches on the bolt, the two wrenches check out and the scale confirms it. When I add the crow's foot the torque output is higher than what it should be but not as high as I suspected. So there must be some other ratio going on there.



Sincerely,

William McCormick

Re: Torque Amp

I have a couple of those Proto and an SK 3/4" drive wrenches, but I prefer this one. It's a bit longer than most of them. Attachment 1719977

Re: Torque Amp

I was thinking about torque wrenches out in the shop................

This got me to wondering as I watched stuff spinning round and round........................I'm not sure where the second torque wrench came from. It might have been just a duplicate buy for some reason, not real sure. Goes back to somewhere around 2010-2012.

Re: Torque Amp

I know I'm late to the party, and math isn't my strong suit.........

Attachment 1719956

Without comparing the torque wrench reading to a known standard, I don't see how you can extrapolate a linear relationship between the straight line force applied to the torque wrench, and the actual torque applied to the fastener. The torque wrench depends on deflection between the handle, and the fastener(the middle of your joined wrenches).

You can apply force to a lever to create torque, then take that torque and convert it into straight line force.......................gears. But the direction changes at the point of conversion

For some duration of time, and amplitude of force...............the torque wrench head is soaking up energy before it transfers your pull on the handle. It's attempting to rotate its head in the opposite direction of the direction you actually want the force applied. You're essentially working with a spring loaded hinge.

I just don't see how you can read that torque wrench with any degree of certainty. Anyways.........the shop ought to be warm by now, and my noodle is getting tired

Re: Torque Amp

I'm really afraid that you're gonna have to bite the bullet, and get something made for higher torque application/measurement.

Attachment 1719950

Attachment 1719951 I don't like the readout on this one. It was a wasn't-anybody-looking auction buy. I guess it's handy for a backup, and to check the other wrench with.

Attachment 1719952 This is the go-to. I like a Vernier scale..........more accurate with finer graduations.

Re: Torque Amp

Put a torque wrench on the crowsfoot, and you're messing with The Universe. The torque wrench only measures torque around ITS HEAD. Without taking direct readings at the fastener, I highly doubt that you can get a satisfactory conversion to apply to your observed torque wrench reading.

Simple thought would be to add the entire rig up, and come out with your beam length. But.........the calibration on the torque wrench is based on deflection when applying torque to the wrench head...............not straight line force applied though your now longer beam to the fastener.

BTW............the crowsfoot, and the torque wrench, have different characteristics when it comes to deflection.

Re: Torque Amp

I can apply torque to anything. It's virtually unlimited. Length of the lever thing.

The only question relevant to designers, is the value at which something radically changes the material to which the torque is applied. Torque is torque.

Re: Torque Amp

This is why the Chinese, and just about everyone else in the World, are kicking our butts

A straight line force creating potential rotational movement

Attachment 1719947

The force imparted to the end of the beam..................Torque

Attachment 1719948

https://www.school-for-champions.com...m#.X76R9emSnIU

You put your socket on the round thingy, and pull/push on the long bar thingy, and ya gots torque applied to the round thingy. The ultimate question, which is uppermost in our pointy lil' heads......................just how much torque can ya apply to the round thingy before it breaks..........or when it reaches maximum clamping force without breaking.

Re: Torque Amp

I only have one steel lever to work with, and I don't want to mess it up. I found some 3/4" stainless steel nuts I couldn't find any 3/4' steel nuts. I have one hex socket and one 12 point socket that size, I can use the 12 point socket on the delivery torque wrench. I might Everdure them to the steel lever if I cannot find steel ones today in my travels. They should be more than big enough to take the force. Even half-inch bolts shear off when we use the Milwaukee Fuel impact wrench, and they stretch when tightening so I figured 3/4" would be perfect. I am going to put a shaft onto the cantilever point on the lever and overhang that point by one foot where I want to make a spot to attach the scale, so I can check the torque wrenches and measure higher torque. There will be a big nut over the cantilever point and then a couple of nuts mounted up and down the lever to see what the different sized levers cause. I kept changing my plan and getting too tired to start a project after dinner, mostly because I am not sure of my plan or available materials. But I am almost there. I should make short work of it once I get started.

I also have a really nice long solid aluminum bar but I do not have any sane way to mount steel nuts to the lever. I was thinking of a custom made steel rectangular box tubing that I could weld up out of quarter inch steel, and then weld a large nut to it and use that, and have a set screw to hold it in place. But then the torque wrench is sitting way above the bar and would cause it to twist. Then I was thinking maybe I could cut off a piece of aluminum by the cantilver and then weld it and bolt it back to the lever under that cantilever or folcrum point so that the wrench was more inline with the spot and nut over the fulcrum point. This way I could just adjust my single nut to any position up and down the bar. And the scale would pull at a point more inline with the wrench.

Sincerely,

William McCormick

Re: Torque Amp

I was up at 4:00 am yesterday, loaded up the truck and on the road by 5:00, drove for over two hours on the way up there and over two ours back, I got home just after 12:00 am today so I did not get a chance to build my lever. But I am working on it. It was a productive day though we decided to take on an extra project. I went to a plumbing supply house, and the Milwaukee truck was there. He gave out $15 meal vouchers to a local restaurant so we had a free lunch. My friend bought the big Milwaukee Impact Wrench and that big extension light and got a free battery. We could have just got the free meal vouchers, but we love tools.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by MinnesotaDave

She is a distraction to be sure

I used substitution of:
Lt = Lc + Lw

Where Lt is combined length therefore:
Lc = length of crows foot
Lw = length of torque wrench

My distraction

Attachment 1719550

Attachment 1719551

Attachment 1719552

Certianly an understandable distraction, I wish I had.

I only started fiddling with the torque wrenches tonight. And I have to be up at 4:00am so I am already past my bedtime. All I was able to prove is that torque is one to one when you use an extension between the torque wrench and a crows foot. Angle of torque wrench does not matter at all.

My own personal observation of a quick attempt is that our formulas is it. I tried a torque I could easily develop and hold and at first I thought the standard formula might be right or pretty close. But when I ran the numbers through our formula darn it was dead on. The problem is that the difference is only like two pounds so I cannot call it. When I finish building my lever with multiple places to try out the wrench it should be very obvious. With the lever I can also measure with a scale at one foot out to get foot pounds. I can also check the calibration of the torque wrenches against the scale I think it well prove worthwhile. Hopefully I can get in and get out tomorrow and get home early and build my test lever.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by William McCormick

I know what happened there Dave, your wife came into the room and whispered Y over X on the square mattress, haha.

Sincerely,

William McCormick

She is a distraction to be sure

I used substitution of:
Lt = Lc + Lw

Where Lt is combined length therefore:
Lc = length of crows foot
Lw = length of torque wrench

My distraction

Attachment 1719550

Attachment 1719551

Attachment 1719552

Re: Torque Amp

Originally Posted by William McCormick

I think there is something with the checking that goes off the rails but the formula is amazing.

Attachment 1719549

Sincerely,


William McCormick

I know what happened there Dave, your wife came into the room and whispered Y over X on the square mattress, haha.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by William McCormick

I am going to use those formulas, to test against them in the real world and see how they stand up to reality.

Here is how I checked your formula, it is the same way I checked out my cumbersome formula.

For a one-foot crow's foot, and a two-foot torque wrench scenario that wishes to achieve 100-foot pounds of torque on a bolt. Both formulae spit out 40 pounds of torque, which means there are 20 pounds of tangential force on the wrench handle to achieve that. 20 times the overall length of the torque wrench and crow's foot is 3, 3 times 20 achieves 60 ft. pounds of lever force on the bolt. Then there are the additional 40 pounds of rotational force calculated by the formula that gives us 100-foot pounds of torque on the bolt combined. These are the tests I plan to do with both wrenches and the scale.

The standard formula says that we need 66.66666666666666666666 foot-pounds of torque at the wrench to achieve 100 foot-pounds on the bolt, divided by two gives us 33.333333333333333333333 pounds of tangential force on the handle of the torque wrench. 33.333333333333333333333 times 3 equals 100 pounds f lever force calculated at the bolt. But we have an extra 66.66666666666666666666 of accumulated torque in the head of the torque wrench on top of the 100 pounds of lever force which should yield 166.666666666666666 ft. pounds of torque to the bolt.

I want to get a large two handle tap handle and add rotational force to the torque wrench head as well just to demonstrate the rotational force's involvement at a rotating joint in a lever.

Sincerely,

William McCormick

I still say that "the new formula" is incorrect.

If the crows foot is clipped directly to the torque wrench, it is being turned by rotational force.
Just so happens both swing in an arc together that is easy to see.

When the crows foot is on the end of a socket extention, it is still being turned by the same force.

Your other hand just balances the torque wrench head. Which should result in a negligible error.

I could be wrong, but I'm going with it

If I'm wrong, then the original time tested formula should include the disclaimer that the longer the socket extension, the less accurate the result. Then that can be tested and a correction for error determined, and an error calculation included.

I would find all of that quite interesting.

Re: Torque Amp

I think there is something with the checking that goes off the rails but the formula is amazing.

Attachment 1719549

Sincerely,


William McCormick

Re: Torque Amp

Originally Posted by William McCormick

Dave this part of your formula works well and it looks neat and easy.

(TD X LW) / (LT + LW) = TS

That is a beautiful thing there.

And it works out for the numbers I tried.

Sincerely,

William McCormick

I am going to use those formulas, to test against them in the real world and see how they stand up to reality.

Here is how I checked your formula, it is the same way I checked out my cumbersome formula.

For a one-foot crow's foot, and a two-foot torque wrench scenario that wishes to achieve 100-foot pounds of torque on a bolt. Both formulae spit out 40 pounds of torque, which means there are 20 pounds of tangential force on the wrench handle to achieve that. 20 times the overall length of the torque wrench and crow's foot is 3, 3 times 20 achieves 60 ft. pounds of lever force on the bolt. Then there are the additional 40 pounds of rotational force calculated by the formula that gives us 100-foot pounds of torque on the bolt combined. These are the tests I plan to do with both wrenches and the scale.

The standard formula says that we need 66.66666666666666666666 foot-pounds of torque at the wrench to achieve 100 foot-pounds on the bolt, divided by two gives us 33.333333333333333333333 pounds of tangential force on the handle of the torque wrench. 33.333333333333333333333 times 3 equals 100 pounds f lever force calculated at the bolt. But we have an extra 66.66666666666666666666 of accumulated torque in the head of the torque wrench on top of the 100 pounds of lever force which should yield 166.666666666666666 ft. pounds of torque to the bolt.

I want to get a large two handle tap handle and add rotational force to the torque wrench head as well just to demonstrate the rotational force's involvement at a rotating joint in a lever.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by MinnesotaDave

Did some moving around for you.

Got rid of "Over Torque" because I don't like it.

Attachment 1719509
Attachment 1719510

btw, Lc is the length of the crows foot.

Attachment 1719511

An example with numbers would seem to indicate your original assumptions are not accurate.
Attachment 1719512

Dave this part of your formula works well and it looks neat and easy.

(TD X LW) / (LT + LW) = TS

That is a beautiful thing there.

And it works out for the numbers I tried.

Sincerely,

William McCormick

Re: Torque Amp

The new wrenches are here the new wrenches are here! And the new scale is here!

Attachment 1719523


I didn't expect them till tomorrow.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by MinnesotaDave

The "new formula" is not any good.

After running through it to make the equivalent functions, using numbers in the example shows it doesn't work.

I highly doubt that there will be so much error (wasted energy) that 325 ft.lbs., minus the error, is actually valid.

I ran the numbers through our new formula and something did not come out right I think. But I am still checking.

Then I ran them through this thing and it seems ok but it does not look organized pretty or easy.

Attachment 1719521

The numbers you put through our new formula, I put through the old formula and it came out and checked out.

I multiplied 150 by (18/21) and got 128.571428571428571 what the standard formula outputs for torque. I then multiplied 128.571428571428571 by (150 / (150 + 128.571428571428571)) which equals 69.230769230769231 the TS or torque wrench setting.

To check" if you take 69.230769230769231 and divide it by 1.5 the torque wrench length you get 46.153846153846154 pounds of tangential force on the torque handle, if you multiply that by the length of the whole lever 1.75 feet you get 80.769230769230769 pounds of foot torque created to the nut, then if you add that to 69.230769230769231 the TS or Torque Wrench Setting you get 150




Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by William McCormick

You have to remember the boxed common formula is only calculating a single one piece lever, the amount of force needed on the handle or the break point between torque wrench and crow's foot, and then reverse engineering to get the torque reading on the torque wrench needed to create that force, but never adding in the rotational ft. lbs. created at the joint, before reaching the force necessary on the torque wrench handle. So you will be snapping some bolts unless you use a socket extension and the exact torque setting that you wish applied to the bolt. Or our new formula in an inline setup.

Sincerely,

William McCormick

The "new formula" is not any good.

After running through it to make the equivalent functions, using numbers in the example shows it doesn't work.

I highly doubt that there will be so much error (wasted energy) that 325 ft.lbs., minus the error, is actually valid.

Re: Torque Amp

Originally Posted by William McCormick

Genius Dave! Together there is nothing we couldn't do.

Sincerely,

William McCormick

You have to remember the boxed common formula is only calculating a single one piece lever, the amount of force needed on the handle or the break point between torque wrench and crow's foot, and then reverse engineering to get the torque reading on the torque wrench needed to create that force, but never adding in the rotational ft. lbs. created at the joint, before reaching the force necessary on the torque wrench handle. So you will be snapping some bolts unless you use a socket extension and the exact torque setting that you wish applied to the bolt. Or our new formula in an inline setup.

Sincerely,

William McCormick

Re: Torque Amp

Originally Posted by MinnesotaDave

Did some moving around for you.

Got rid of "Over Torque" because I don't like it.

Attachment 1719509
Attachment 1719510

btw, Lc is the length of the crows foot.

Attachment 1719511

An example with numbers would seem to indicate your original assumptions are not accurate.
Attachment 1719512

Genius Dave! Together there is nothing we couldn't do.

Sincerely,

William McCormick

Re: Torque Amp

Did some moving around for you.

Got rid of "Over Torque" because I don't like it.

Attachment 1719509
Attachment 1719510

btw, Lc is the length of the crows foot.

Attachment 1719511

An example with numbers would seem to indicate your original assumptions are not accurate.
Attachment 1719512