122 replies to this topic

[Dusky]

If using an open end spanner/wrench, you can get a decent torque near enough by first practicing with a double nut using a bench vice and your existing torque wrench....hold one end of double nut with the torque wrench, other with the open end and learn what the 60-70 ft-lbs feels like. Repeat on the ball joint.

There are also tricks like taking an open end or combo open end/closed end spanner and using a suitable nut on the other end to then connect the torque wrench to. If you keep it at 90 degrees to the ball joint then the length of the spanner does not change the effective torque at the torque wrench end. Here's a snazzy Motion Pro tool for this:


https://www.motionpr...dapter-08-0380/

Hold your horse right there.
It WILL require an adjusted torque setting as stated in the picture.
You're creating extra leverage. Without any adjustments you ll be overtorqueing it by a lot.

Actually, it states NO ADJUSTMENT needed if held at 90 Deg....and adjustments needed if not at 90 Deg. That's the whole point of the adapter part. As I said, this can also be done with a homemade adapter or even using a double up pair of nuts locked to a bolt....then one end in the combo wrench end and one end in the torque wrench/socket. Held to 90 deg and no adjustments needed.

That's a physical impossibility.
You can state whatever you want, you will increase leverage in the real world.

[Tremelune]

I...I posted a video with proof. Here's more:

 

http://www.fordservi...ula_main_en.asp

 

You don't need to adjust torque when the adapter is at 90° because of geometry and the tangential direction of the force applied.

[Ethel]

You could say the lever is longer, effectively the hypotenuse, but the turning moment that "clicks" the wrench isn't perpendicular to the hypotenuse either.

 

Or you could just imagine you had a parallelogram with a hinge at each corner with the actual and your "virtual" torque wrenches making up parallel sides. You can see the 2 wrenches would behave identically  even though the hinges wouldn't allow you to transmit any torque between them.

 

Then, if the torque range is as wide as stated, just rig it up so you stand on yer bathroom scales and pull the spanner upwards.

[Pete649]

After watching the linked video in Tremelune's post above I had to find out what was going on mathematically as this was bugging me.

 

I did some vector calcs (and the hypotenuse does come into it) using maths I last used 40 years ago and it does work. The force is exactly the same regardless of the length of the extension if at 90 degrees.

 

All I have a a bunch of scribble on an A4 sheet though. It just shows the forces are the same, it is not a proof as such.

[Pete649]

You could say the lever is longer, effectively the hypotenuse, but the turning moment that "clicks" the wrench isn't perpendicular to the hypotenuse either.

 

 

That is exactly it, the lever is longer via the hypotenuse but the force to the 'effectively longer lever' is now vectored thus reducing the actual force being seen by the longer lever. The more you increase the length of the extension the more the vectoring reduces the actual force being seen by the longer lever and one compensates the other.

[nicklouse]

interesting

http://www.fordservi...ula_main_en.asp

 

[nicklouse]

and if you like moving pictures (some of his words are not right at the start about the grip position though)

https://youtu.be/4dsAvFNVGRE

 

[Ethel]

 

You could say the lever is longer, effectively the hypotenuse, but the turning moment that "clicks" the wrench isn't perpendicular to the hypotenuse either.

 

 

That is exactly it, the lever is longer via the hypotenuse but the force to the 'effectively longer lever' is now vectored thus reducing the actual force being seen by the longer lever. The more you increase the length of the extension the more the vectoring reduces the actual force being seen by the longer lever and one compensates the other.

 

 

You can avoid any trig, we've got  3 right angled triangles with 2 bisecting bisecting the right angle of the other, so they're all similar.

[IronmanG]

Just try it. Put a bolt in a vice and put a nut on, torque to 50 with the torque wrench then put the spanner at right angles and torque it again. Dont need scribbles and paper. It's easy to replicate

[nicklouse]

Just try it. Put a bolt in a vice and put a nut on, torque to 50 with the torque wrench then put the spanner at right angles and torque it again. Dont need scribbles and paper. It's easy to replicate

Or watch the video above.

[IronmanG]

Ye didnt do that. What happens

[nicklouse]

it proves that at 90 the result is correct.

 

he set a torque wrench and test it on a torque reader. and then does some tests.

 

watch it.

[IronmanG]

Dont need to now? Like I said easy to replicate

[Pete649]

Dont need to now

 

I do

[Ethel]

Just try it. Put a bolt in a vice and put a nut on, torque to 50 with the torque wrench then put the spanner at right angles and torque it again. Dont need scribbles and paper. It's easy to replicate

Actually, that wouldn't quite be a fair test because of the difference between static & dynamic friction. To be really accurate you'd need to slacken & retighten it & go off the angular position, better still repeat several times.