Can't Balance Propellers / Can't Achieve a Passing Grade
If you’re struggling to achieve a satisfactory balance grade on your propellers using the dynamic balancing software, try these troubleshooting steps:
1. Check your input values
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RPM input
Ensure that the RPM entered is very close to the RPM at which the propeller will actually operate in flight. If the test RPM is too low, the software will be unable to gather sufficient data to detect imbalances. -
Rotor mass / rotating mass value
Double-check that the mass you entered includes all rotating components: propeller, hub, screws and hardware, any adapters, and the motor's rotating parts (rotor). If your mass is incorrect, it will be challenging to calibrate the balancer. - Correction radius
Ensure that you are placing your correction weights as close to the indicated radius as possible. Placing the correction weight closer to the tip of the propeller blade will require less mass to achieve the same corrective effect. However, for aerodynamic or practical reasons, you may prefer to place correction weights closer to the hub. This is also possible but will require more mass to achieve the same correction.
2. Mechanical/setup integrity
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Secure the Flight Stand properly
The balancer detects vibration. If the stand is not well secured, the entire support structure can vibrate, corrupting the readings. Ideally, secure your stand to a solid foundation (ex. concrete or steel frame already secured in the ground) to minimize stray vibration. -
Correction placement
Confirm that you are putting the correction weight on the correct blade, as per the diagram or the software. A simple mis-assignment (ex. putting counterweight on the wrong blade or entering the wrong blade number in the software) will result in incorrect readings. - Pre-balance the motor / rotor assembly
If possible, balance the motor by itself first. This ensures that you start with the motor as well balanced as possible before adding the propeller.
3. Limitations of the balancing feature
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Single vs. multi-plane balancing
The Flight Stand balancer supports only single-plane balancing. If the root cause is a multi-plane imbalance (ex. imbalance distributed along the shaft length), then you likely won’t be able to correct it with this tool. In that case, you’ll need to rely on other fixes, such as reducing mechanical defects or pre-balancing components. - Reassess your target grade
If you’ve tried all of the above and still cannot achieve the quality grade you want, you may have to accept a higher balancing grade. Mechanical limitations, structural tolerances, and aerodynamic constraints can sometimes prevent further improvement.