Drone repair is crash-driven: bent arms, shattered props, cracked shells, bad IMUs, camera gimbal hits, and batteries that no longer balance. Consumer and prosumer quadcopters share patterns — frame damage, motor/ESC faults, vision sensor misalignment, and firmware that refuses to arm after an impact. Always power down and remove batteries before repairs. Balance props and check motor smoothness after any crash. Calibrate compass/IMU only with the manufacturer procedure after mechanical work. Counterfeit batteries are a fire risk; stick to known-good packs. DIY-friendly work includes prop and guard swaps, arm replacements on modular frames, shell clips, and many gimbal dampener fixes. Leave flight controller board-level work and sealed waterproof units to specialists if you lack microsoldering gear. Browse Drone guides by brand and model for crash-repair sequences and calibration notes that match your aircraft.