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Electric Flight Propeller

It is important to note that most Electric Flight Propellers in general do not come pre-balanced. In some cases they can be bought at a higher price if one does not wish to do the balancing by hand. The technique to do so after purchase will be described here.

Electric Flight Propeller Balancer

A prop balancer will be needed. One can purchase a prop balancer at their local hobby store. The most common type that will work for plane props, boat props and small car tires is the magnetic balancer type.
When the prop is properly placed on the balancer, the heavy tip will tend to drop to the bottom naturally by gravity. This will alert the user of which blade to remove material from to balance the prop. It is absolutely important to understand where to take material away from. Material should only be removed from prop side that does not affect pitch. When looking at a plane from the rear you are looking at the side which performs all the work and turns rotation in to thrust. This side must be left alone. Material on the blade that drops to the bottom while on the balancer, will be removed from the opposite face of the prop blade. This would be the face of the prop seen from viewing a plane from the front. It will be required to constantly check the balance of the prop as you do not want to take too much material away. Continue to remove material from the front face of the heaviest prop blade.  Once complete, the prop should be well balanced.

Selecting the proper Electric Flight Propeller

Choosing the right prop for an application is one of the hardest selections. Too little of a prop will not get the plane through the air while too large of a prop will certainly destroy electrical components.. It’s not voltage that destroys motors, it is current and maximum rotational velocity that destroys motors. Current is controlled by the load placed on the motor.

It is recommended to seek advice if one does not know what a conservative prop would be for their specific application. Every combination is different!

Knowing which prop would work best for each power system comes mostly from experience.  If you are unsure of which prop is best, please ask in the Radio Control Info Forum

A larger prop or higher prop pitch increases load. Increased Load will result in an increased current draw.
A smaller prop or a lower prop pitch will decrease load. Decreased load will result in a decrease of current..

An advantage to using a larger prop at slower RPM’s is thrust. Higher thrust is excellent for slower, heavier flying planes. Efficiency is also higher for larger props as there is less possible slippage.
The advantage for a smaller prop running at higher RPM’s is faster pitch speeds.  When higher top speeds are required or desired a setup using a smaller prop at higher speeds will be best suited. For this type of setup the plane tends to be sleek and light weight.
Advantages: 2 Blade vs. 3 / 4 Blade when diameter and pitch are equal.

2 Blade
- Higher Top Speed
- Less Load on motor
- Motor will turn higher RPM’s

3 / 4 Blade
- Higher thrust / Faster Acceleration
- More Scale Appearance