bandsawing steel stock - what am I doing wrong?

Like they said, step pulley's, or why not maybe say a 2" pulley at the motor, and maybe a 8" pulley at the bandsaw.
That would allow you to crank up the speed a little at the motor, and maybe get a little more torque.
Although they do say the torque is good on these at any speed.
Then some guys say your better off with a little more speed.
i just got a 1/2 HP for my lathe. So I will see how that goes.
My experience on these DC motors is limited.
It is this motor. Although It is really TEFC, not TENV.
http://www.amazon.com/gp/product/B00KA2R7TA/ref=od_aui_detailpages00?ie=UTF8&psc=1

I have been following this thread and it got me to thinking about working on my Powermatic 14" wood cutting bandsaw (Model 141). I have been looking for a while for a stand alone vertical metal cutting bandsaw and nothing ever seems to become available. I then thought of trying to find a drive system for a Powermatic Model 143, metal cutting bandsaw. Now this idea of using a 90volt DC 1725 RPM motor with SCR speed controller really seems like the smart and economical way be able to lower the blade speed for metal (changing the blade, of course) while still being able to increase to the max for cutting wood.
I did a bit of math to calculate how slow I would need to turn the drive pulley to get the saw blade to be moving at 75 FPM. (This would me the slowest I would expect to have to turn for cutting steel.) I found that the motor would have to be turning at 40 RPM. Here is how I figured this.
Motor speed =X
Drive pulley dia.= 3"
Driven pulley dia.= 6"
Dia. of bandsaw wheels= 14"
Driven wheel speed= Y RPM
Speed of blade = 75 Feet per minute(FPM)
75=Y*circumference of band saw wheels / 12
75=Y* 43.9/12
Y= 20 RPM
20 RPM= X * Drive pulley dia./driven pulley dia.
20 =X * 3"/6"
X= 40 RPM
Now if this correct what I am wondering is would the motor have sufficient torque at this reduced speed to be able to be effective at cutting steel. Assuming correct blade and appropriate feed pressure?
Thanks for all your help,
David
 
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