I needed a way to cut steel, aluminum, brass, and wood with my band saw which is an older tool I have had for 30 years. The Delta is a good saw but to fast for steel. I added a 19:1 gear reducer and a 2:1 pulley setup to match up with my 6000 rpm variable speed tread mill motor. So now I have a saw that cuts just about anything you can get a blade for at just about any speed you require.
My first attempt was to use the tread mill motor with just the smallest pulley I could fit on it and use the existing drive pulley on the lower band saw wheel. The rpm reduction was not enough. I actually "threw" a tire due to over speed. The other thing was the lack of torque using the tread mill motor.
This new setup with the 19:1 ratio gear box solved both problems.