Chemical etched encoder discs for drones are precision patterned metal rotary components manufactured by photochemical etching, designed for optical or magnetic encoders inside drone brushless motors and servo actuators. Common substrate materials include stainless steel, copper, nickel, and Kovar, with typical thickness ranging from 0.03mm to 0.2mm.

Manufacturing Process

1. Metal sheet degreasing and surface polishing to guarantee uniform surface quality.
2. Laminating photoresist dry film on both sides of the metal sheet.
3. UV exposure using custom optical pattern artwork with precise angular slots and index marks.
4. Developing process to wash away unexposed photoresist and expose the pre-designed pattern.
5. Double-sided chemical etching to cut through or partially etch the precise slot and window structures.
6. Photoresist stripping, precision cleaning, inspection, and optional surface passivation or plating.

Core Advantages

• Extreme angular accuracy: Consistent slot width and pitch to ensure stable speed and position feedback for drone motors.
• Stress-free and burr-free. No mechanical cutting force, so thin discs stay flat without warping, critical for high-speed drone rotation.
• Ultra-thin metal options, helping reduce overall motor weight and lower drone payload burden.
• Fast prototyping without costly hard tooling, ideal for drone R&D iteration and small-batch customized encoder patterns.
• High repeatability for mass production, maintaining tight tolerance across large batches of encoder discs.

Application Fields

• Brushless motor optical encoders for multi-rotor consumer and industrial drones
• UAV servo motor position feedback discs
• Drone gimbal stabilizer encoder components
• Small unmanned helicopter rotary position sensors
• Compact autonomous navigation rotary encoding modules

Design Notes

• The slot width and pitch must match the optical sensor resolution; tighter resolution requires finer etched features.
• Thin encoder discs need structural reinforcement where large open areas exist to avoid vibration deformation during high RPM operation.
• Symmetrical pattern design is essential to reduce mass imbalance and vibration during high-speed rotation of drone rotors.
• Material selection: stainless steel offers good rigidity, while copper provides better thermal conductivity; anti-corrosion treatment is recommended for outdoor drone applications.