swivel adapters/extensions + torque wrench

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Going to be doing some suspension work and if possible would be nice to torque the fasteners back in to spec. I am however a bit confused here.

I've heard that an extension bar will cause an overtorque situation if you don't compensate for it. But what about a swivel adapter? Does that affect the picture as well?

I've googled and can't find a straight answer that my math challenged brain can understand.
 
More likely will cause a UNDERtorque, as it will twist somewhat. Though the amount is probably so low as to be almost negligible. This is how those 'torque sticks' work that tire shops use on impact guns. They twist and dump torque when it gets near its rating.
 
I would worry more about the swivel adapter. The extension would be negligible.

Sometimes you just can't really get to something to torque it. Torque by feel the best you can......
 
I have some impact extensions. According to the torque wrench's manual:

Quote:
Regular socket extensions which extend directly under the drive head along the axis of rotation of the ratchet do not affect the calibration of the torque wrench.


So just a straight extension should be no problem.

Which leaves the issue of the swivel adapters. I was afraid that would complicate matters.
 
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A straight extension won't affect torque. An angle drive adapter will, though. You'd need a constant velocity joint to ensure the torque on both ends was the same.

A swivel adapter will transmit different amounts of torque and rotation depending on where the two pins are relative to the angle. You can see this for yourself by sticking two extensions into the adapter, bending it about 70 degrees, and slowly rotating the two extensions. With a small angle the error is not too large but as the angle increases the errors increase.

You can also measure torque with a conventional wrench and a spring scale. You have to determine the distance from the center of the fastener to the attachment point of the scale and be sure that the scale is pulling at a right angle to the wrench.
Simple math tells you that (1 foot/distance along wrench)x force on wrench will give you the torque delivered to the fastener.


Using a crowfoot adapter with a torque wrench will make your torque reading lower than the actual torque if its opening is opposite the wrench handle.

The torque sticks used on impact guns rely on the fact that the impact gun rotates a certain number of degrees per impact. Twisting the torque stick that number of degrees will result in the desired torque at the socket end of the stick. Used in a steady state situation (as with a manual torque wrench) they will have no effect on the torque delivered for a given reading on the torque wrench.
 
Sounds like using the swivel adapters is gonna be a PITA then. I don't think the angle is always going to be a nice 45/90 degrees. It'll be odd numbers and changing depending on how I have to orient things to fit up and in there on the fastener.

Bummer.
 
Originally Posted By: mahansm
The torque sticks used on impact guns rely on the fact that the impact gun rotates a certain number of degrees per impact. Twisting the torque stick that number of degrees will result in the desired torque at the socket end of the stick. Used in a steady state situation (as with a manual torque wrench) they will have no effect on the torque delivered for a given reading on the torque wrench.


Interesting! Didn't know that was how torque sticks worked.

So, the torque stick will be inaccurate if the impact gun has a different number of impacts per rev than the torque stick was designed for. Makes me wonder about twin-hammer vs jumbo single hammer etc. Or do all guns have the same number of impacts per rev of the gun?
 
Originally Posted By: George7941
Originally Posted By: mahansm
The torque sticks used on impact guns rely on the fact that the impact gun rotates a certain number of degrees per impact. Twisting the torque stick that number of degrees will result in the desired torque at the socket end of the stick. Used in a steady state situation (as with a manual torque wrench) they will have no effect on the torque delivered for a given reading on the torque wrench.


Interesting! Didn't know that was how torque sticks worked.

So, the torque stick will be inaccurate if the impact gun has a different number of impacts per rev than the torque stick was designed for. Makes me wonder about twin-hammer vs jumbo single hammer etc. Or do all guns have the same number of impacts per rev of the gun?


I don't think that matters. Sometimes if I can torque another fastener the same size I will then go to the other fastener that I could not access and go by the feel of the previous fastener.
 
When you get a torque stick or new gun you actually have to test the gun and stick together to see what kind of torque you are getting.

For instance most Inger 231 you just crank it all the way up and good to go.

My Matco/inger Ti you have to run it on LOW or it will over torque the nut.

Must test it!!!

As for the Torque wrench if you are under 6" on the extension forget it. If you have to use longer and it is not super delicate like engine heads forget it too. Engine's I would look up the correction factors. try not to use Swivels but a mild angle should not be too far off try to go as straight as possible or even with a Crows Foot (correction factors available here too).
 
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