On Mon, 21 Jan 2008 11:49:57 -0800 (PST), eljainc
wrote:

Hello,

I am determining the technique used to measure torque on a linear
motion system, using a stepper motor with an ACME lead screw attached
to it. I learned from one source that one could use a torque wrench
(preferably a digital one). Does anybody know the exact steps needed
to use one of these wrenches to measure torque? I know a fish scale
could be used also, but I need precise values. If there is any other
way other than these two, I would like to hear.

There are many ways to do this. You need to define what you mean by
"precise", along with what your constraints are regarding cost and
time spent and what resources and skills you have available to you.

It would also be useful for you to decide whether you want to measure
the torque required by the load or the torque available from a given
motor.