Mechanical Power Calculations

I am running a spread sheet on some Jameco motors. The catalog gives gm-cm and rpm. How do you calculate the mechanical power output in watts?
Thanks
b r a d @ a i v i s i o n . c o m
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Brad Smallridge wrote:

P=2*pi*n*T P=power pi=3.1415....... n=rpm T=Torque
This is from memory so someone correct me if I'm wrong.
Matthew
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Matthew Gunn wrote:

Hmm, I'm working from memory, too, but the units don't look right... The OP had gm.cm, so to get to SI there's a division by 10^5 And watts are Nm/s, so there's a g=9.81, and a 60 for the RPM to seconds. So I'd say:
watts = gm.cm.RPM x (2*pi*9.81)/(60*10^5)
and that seems to jibe with a quick turn around my Evershed & Vignoles "PowerRotor" circular calculator...
Anybody with a crib-sheet?
Geoff.
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Geoff wrote:

Yep, I should have mentioned T must be in Nm.
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There is also the issue of what is listed in the Jameco catalogs. Running torque or stall torque. Also an issue I suppose. Just looking for an easy answer.
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