force required to spin vaccuum fan

[Bruceb]

What kind of devices have a 2 stage vac?
Bruce

[martin417]

Originally Posted by Bruceb

What kind of devices have a 2 stage vac?
Bruce

Ours came from a shop vac, but my old Rainbow at home has a 2 stage impeller also.

[Bruceb]

Martin, what belts did you use. Is the cheapest o.k.?
Bruce

[DonRotolo]

Originally Posted by Bruceb

Is the cheapest o.k.?

Cheapest is always just that: Cheapest. Over the years we have found that Best tends to work better and last longer. Build using the highest quality components you can afford.

Of course, for prototypes, cheap is usually fine.

[martin417]

Originally Posted by Bruceb

Martin, what belts did you use. Is the cheapest o.k.?
Bruce

Avoid "shade tree engineering"! Don't just guess and try it, the build season is too short!

Belt manufacturers publish data on capacity of belts, advantages of construction and materials, etc. The data is often in the form of a graph, plotting belt capacity (in horsepower) against the speed (in RPM) of the fastest pulley. do not exceed the spec.

You should also look at the max torque. You will probably have to ramp up up the speed of the motor to avoid slipping the belt or the pulley.