mag00,

As far as I can determine, the formula is correct as posted.

What I haven't explained as well as I should (not a very good teacher) and what you don't seem to yet grasp is this:

The torque wrench is calibrated with the center of rotation at the bolt center and a given force applied at a given distance along the handle.

When an extension is added, the square-drive end of the torque wrench is no longer operating in the same swing radius relative to the center of applied torque and the calibration of the wrench is now altered.

Furthermore, the extension has increased the total effective distance from applied force to the point of application and the relationship between the 2 changed factors must be resolved to regain accuracy.



The formula is not just "close enough for mechanics". Mechanics are the very folks who need, want and expect the most accuracy. The formula was developed to give mechanics the exact benefit of accuracy in work that most are proud to do and damned good at doing and no amount of math or trig comprehension will change the existing facts.

I'd suggest that you find someone who'll give you the answer you want to hear. Being a "perfectionist" is one thing, but it seems an exercise in futility to attempt to prove experts wrong at their own business.... but hey - if you can do it, go ahead.... you might find it "up there somewhere".

Now on the off-chance that I still haven't understood what you want to know, there are "other" factors that affect torque values - i.e. friction loading, thread pitch, etc. If the adjustment corrections you're looking for fall into those types of "perfectionist" areas, I can't help you - that's beyond my "need to know" or desire to understand - much less try to explain.

Frank <img src="/forums/images/graemlins/cheers.gif" alt="" />