RC Helicopter Shaft Collar 2.6 x 4 x 9F Hirobo HI2521093  [HI2521093]

Precision collar for rotor shafts

This Hirobo HI2521093 collar functions as a compact shaft stop used in model helicopter rotor and drivetrain assemblies, providing a defined axial location for rotating parts. The part code indicates the nominal sizing for shaft compatibility.

To fit the collar, place it at the required axial point on the shaft and tighten the set-screw or clamping mechanism. Confirm alignment with neighbouring components, use the correct hex driver and torque, and inspect rotation and clearance after securing the part. Thread locker applied sparingly can improve resistance to vibration where needed.

The collar is useful for preserving alignment, reducing play in shafts, and supporting consistent control geometry while tuning models. Always double-check the collar dimensions against your shaft and mating parts listed by the supplier before installation.