To convert from 2 blades to 3 blades you want to decrease the
total blade area and increase the angle of attack (or pitch) to
overcome the increased drag of the third blade.
The general rule is to DECREASE propeller diameter by 1-2”,
and DECREASE by 1-2” the propeller pitch. It is all right to keep
the same pitch when going from 2 blades to 3. As always, check your performance with a meter to make sure that you are not over powering the motor.
Prop hole size - Most Master Airscrew Propellers have two hole sizes because
they are piloted in the back of the propeller to facilitate reaming
should you need to enlarge the hole. The first number is the
hole size; second number is the pilot size.
6” through 7”: 1/8” and 3/16”
8”: 3/16” and 1/4”
9” through 13”: 1/4” and 5/16”
14” through 16”: 5/16” and 3/8”
Except where noted, these propellers are for electric motors or gas/glow engines.
Prices, product specifications, and product availability are subject to change without notice.