Drone: a grinding motor or a broken arm, before it falls out of the sky
On take-off one of the motors whines or grinds. The drone still flies, but a motor stopping in flight means a certain fall.
A drone's motors spin at several thousand rpm on tiny bearings. Sand, a wrapped blade of grass, a knock on the shaft, or simply wear, and the motor starts rubbing. The controller compensates for a while, then the motor stalls.
The signs to take seriously
- One motor louder than the others, or a high-pitched whine.
- A motor that turns less freely by hand (drone off).
- An arm cracked at the folding hinge, or with play.
- Drift in flight, the drone “pulling” to one side.
- A motor or ESC error message in the app.
The repair
We replace the motor (soldered on the arm, with its wires running through the hinge), or the complete arm with its motor when the hinge is damaged. On some models the motor controller (ESC) on the main board can be affected after a stall; that is a component-level repair.
Then: check of all four motors, balancing of new propellers, calibration, test flight.
Prevention
Inspect the motors after every landing in grass or sand, spin them by hand, and never persist with a grinding motor. “From” prices per model are on the prices page.
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