I came across this nifty bit of software for converting measurements whilst looking at stepper motors. was having fun comparing the holding torques as some were in metric some in imperial. it converts length, force, torque and many many more. I don't know if your already sorted out for this but take a look at
best of all its free to use and pass on. all the author asks is to be dropped a line letting him know what you found it useful for.
Surely a good tool to have in your set?
Best Regards,
Simon