At 04:40 PM 1/6/2001, Joe Romas wrote:
>     I did draw a line on a pencil and flipping it end for end does indeed
>reverse the rotation therefore putting stress on the opposite surface!

Ah...I didn't explain well enough.   Let's say the pencil is the left-side
axle, therefore your right hand is the drive and your left hand is the
wheel.  Use your right hand to torque the shaft forward against your left
hand, and draw arrows on each end of the pencil opposite to the direction
of torque  against the shaft (so arrow on right end will be pointing back
toward you, and on left end will be pointing forward).  Now flip the shaft
and guess what -- the arrows are pointing the same way.  Now leaving the
arrows as they are, pretend your left hand is the drive and your right hand
is the wheel.  Voila -- arrows are now pointing in the same direction as
the torque you're exerting on the shaft, showing that the shaft (and hence
joints) are being torqued in the opposite direction.

cheers
david
ps -- I myself have flipped shafts end-for-end in my time...and told Larry
Hamm he was full of it...until I took the Hamm test myself.

David Beierl - dbeierl@attglobal.net