Using torque extension bars with a break bar?

[twr7cx]

Does anyone know if I can use a torque extension bar with a breaker bar in order to torque a nut up to the correct torque?

e.g. if I didn't have a torque wrench handy, but do have a set of these and a breaker bar will it work:

[Tank]

I'm not sure, I think they are designed to work an air/electric Impact wrench, never seen one used with a breaker bar, Regards Frank.

[roverrescue]

I believe the concept is that once the specified torque is applied, the shank of the "torque bar" then rotational flexes such that further torque is not applied to the nut.

When in use with a rattle gun, the applied torque over and above the specified value is essentially absorbed by the rotational flexing.

I guess, theoretically with a breaker bar the same principle would apply and you would stop tightening when the bar flexes instead of rotationg the nut.

Both these and torque wrenches are still relatively rough methods of achieving repeatable bolt tightening - cue Bush65

But a torque wrench is damn handy to have around when working on a landy?

I have been meaning to get one for wheel nuts but instead just use the rattler with judicious application. And besides with onboard air I have the rattle to take em off trackside anyways!

S

[Blknight.aus]

Yep put as long a breaker bar on em as you like, they have a slip. Clutch in them that prevents you from going too tight, I would use them other than for wheel nuts as they generally go +/- 10% which is outside the normal +/- 5% for Spannering.

[roverrescue]

You sure about the clutch in them purdy coloured ones dave?
Im guessing they are just the shanked down twisty jobs?
See how the green one is real skinny ie will twist early with not much torque whilst the light blue one is
a little more "rotationally enhanced in the transverse plane" higher torque before it twists and abdorbs the impacts from the rattler.

S

[Blknight.aus]

The ones that I've looked at (5 in a box at common wheel nut type tensions) have a slip clutch in the head end that you stick the driver into.

I wouldnt want to be relying on one that just flexes through the shank to stop it from ticking over any further, how the hell would you check it off for calibration?

[twr7cx]

You sure about the clutch in them purdy coloured ones dave?
Im guessing they are just the shanked down twisty jobs?
See how the green one is real skinny ie will twist early with not much torque whilst the light blue one is
a little more "rotationally enhanced in the transverse plane" higher torque before it twists and abdorbs the impacts from the rattler.

S

I believe the above description is correct. I have not seen these with a slip clutch.

[Blknight.aus]

These are the ones I thought we were talking about

HSUTECH ENTERPRISE CO., LTD., Professional & Industrial air tools, Pneumatic tools Taiwan, Innovation Air tools Taiwan, New Patented Air Tools Taiwan

[twr7cx]

These are the ones I thought we were talking about

HSUTECH ENTERPRISE CO., LTD., Professional & Industrial air tools, Pneumatic tools Taiwan, Innovation Air tools Taiwan, New Patented Air Tools Taiwan

Ok, they are cool, but the slip clutch in the socket, not the extension.
The issue with them though is that they are all set at 100nm torque which is too low - the Land Rover Discovery 2 torque setting is 140nm and my Ford Falcon is 150nm!

The way the torque extensions I posted above work is that they flex when over the specified torque level instead of applying the torque to the nuts. They're generally used on rattle guns.

[Blknight.aus]

they also snap if your rattle gun has had its wheat bix....

one of the appies at 382 was given a set by his missus as a birthday present he took em in to work to use on his ricer and the one that was supposedly right for his vehicle snapped while on the last wheel. The rest were in the bin and he told his missus they got stolen.