Use of Extension Bars with Torque Wrenches

[Lionelgee]

Hello All,

Is using an extension bar on torque wrenches an acceptable practise?

I just torqued up the pressure plate bolts one of my Series III. To clear the pressure plate I had to use a 75 mm long 1/4 inch drive extension bar on the torque wrench. The torque is noted as between 22-25 lbf ft or 3-3.5 Kgf m according to the Green Bible (p. 33-1).

If the whole concept of a torque wrench is accuracy - does using an extension bar effect its accuracy? Or is the difference so minimal with or without an extension bar that it is nothing to consider?

Kind regards
Lionel

[Blknight.aus]

so long as the head is inline with the bolt the reading is accurate.

it might take a little more rotation due to flex in the extension.

if you're doing torque to angle stuff you need to make the allowance for the twist.

[Lionelgee]

Thanks for the reply Dave, it is much appreciated.

I went to use my ratchet torque wrench and found out that its lowest setting is 40 Nm. I went back to the shed and found my beam style torque wrench. I remembered your advice about how time consuming they can be when compared to the ratchet style. You were dead right. This is compounded when you are leaning over the bottom of the door frame and crouching over the chassis rails.

Best of luck with the job hunt!

Kind regards
Lionel