Hirobo HI2521093 collar 2.6 x 4 x 9F shaft collar for RC helicopters  [HI2521093]

Shaft collar for model helicopters

This Hirobo HI2521093 collar is an RC-scale shaft collar intended for use in model helicopter assemblies where a compact retention or alignment solution is needed. The part name encodes its sizing reference, and the collar functions as a mechanical stop or locator on shafts used in rotor and drivetrain subassemblies.

Installers typically position the collar on the shaft at the required axial location and secure it using the collar's set-screw or clamping feature. For reliable performance, verify axial clearance and rotational runout before final tightening, and use the appropriate hex driver and controlled torque. Thread locker may be applied sparingly if the application requires added vibration resistance.

As an RC accessory, the collar helps maintain component alignment, reduces lateral play in shaft assemblies, and supports predictable control linkages or rotor geometry during setup and tuning. Confirm fit against the shaft diameter indicated by the part code and the mating components on your model before installation.