Looking at the documentation from most of the quality manufacturers of torque wrenchs (Proto, Snap-on, Norbar, etc..) I see that I can increase the "range" of a torque wrench by putting an "in-line" extension on the *drive* end(not the handle end. By scaling the reading/click setting accoring to a formula which accounts for the length of the extension, one can apply a torque that is greater than the wrench would do if there was no extension. (Just so I'm clear, this is not the typical sort of extension that goes perpendicular to the wrench, but is instead in line with the axis of the wrench.)
Now - I've searched far and wide and cannot find anyone who actually makes or sells a simple extension that I can buy. I'm looking for one that has a 1/2" square female socket on one end (where the drive end of the torque wrench fits) with a 1/2" male square drive on the other end. I've seen ones where the drive ends are open-ended spanners, box ends, etc, but can't find a simple square-square adapter.
Here'a a link to a guy who's built a homemade version:
Anybody have a source for such a thing?
-Dave