Brushless Motor Thrust Stand
π Overview
Testing thrust before you build is an old rule in RC and drone work. This project builds a bench thrust stand around a load cell and an Arduino: bolt on a motor, ESC, and propeller and it shows thrust, current, power, and efficiency in real time - real numbers you can use when choosing a propeller.
A 16x2 LCD shows the data live, the base is 3D printed, and the whole rig costs just a few tens of dollars.
π§° What you need
- Load cell (beam type)
- Arduino board x1 + 16x2 LCD display
- Motor under test + ESC + propeller
- Current sensor (ACS712 or similar)
- Buzzer, 2-pin/3-pin screw terminals, potentiometer
- 3D-printed base and brackets (STLs provided by the author)
π§ Step by step
Gather the parts
Pick the load cell range to suit your motors - don't exceed it
The potentiometer is used for calibration and fine adjustment
Build the circuit
Wire the load cell signal to an Arduino analog pin and the LCD over I2C or in parallel
Make sure the ESC signal line shares a common ground
Solder and assemble
Fix the load cell to the base and mount the motor bracket on its free end
The load cell must be loaded exactly along the thrust direction
Fit the base
The printed base must be rigid - motors vibrate hard during tests
Add anti-slip pads or ballast underneath
Flash the code
The firmware reads the load cell and current sensor and computes power and efficiency
Calibrate the zero point on power-up, then verify the reading with a known weight
Test it
Increase throttle gradually and record the thrust curve at each step
Watch motor and ESC temperature; holding full throttle for a long time will overheat them
Wrap-up
The data guides propeller choice, motor choice, and endurance estimates
Swap props on the same motor and the efficiency difference is obvious
π‘ Tips
- Calibration matters: record the no-load zero first, then set the scale factor with a known weight
- Keep the propeller well away from people and anything flammable, and use a guard
- Logging voltage and current to compute efficiency is far more useful than thrust alone