In the flavour of this thread is there also a rule of thumb for maximum RPM expected out of motor or even maximum RPM where torque is still 90% of the 70% if you know what I mean

So you buy one of those high torque motors but can't get a torque to speed curve from the seller.
What can you "simply" do to generate a curve that would be "somewhat" indicative of preformance?

Now a stepper mounted in a fixture and it's shaft turned over a range of speeds ( verticaly in a vise and driven by a mill / drill press chuck) you could measure the voltage generated out of the wiring configuration and plot the speed to the generated voltage at say 24 volt output. Now I'm brain dead.............
RICH

Rich,

Not exactly what you wanted but have a look at this posting :-

http://www.machsupport.com/forum/index.php/topic,4764.0.html

Also, a helpful reply from Mariss Freimanis (The Gecko man) on the Yahoo group showing what you can achieve with steppers in this thread :-

http://finance.groups.yahoo.com/group/geckodrive/message/13626

Ian

Thanks Ian,
Torque gages and wrenches come in handy and have used them to check holding torque and more importantly to see outcome of table adjustments and required torque to move a table.  Need to think more about that other post.
The cloud over my head envisioned some formulas and general guidelines into an excell spread sheet.....and magic
.....there's a "ball park graph" for an unknown stepper!
RICH