Hirobo HI2521122 RC Helicopter Shaft Collar 5 x 6.5 x 12.5  [HI2521122]

Helicopter shaft locator description

This Hirobo collar (HI2521122) serves as an RC-scale shaft collar for general helicopter parts and assemblies. Confirm the marked 5 x 6.5 x 12.5 dimensions before fitting to your model's shaft and component stack.

It functions as an axial locator and spacer within rotor linkages, swashplate stacks and other shafted subassemblies where limiting end-play is required. The simple profile is intended to work with the existing mounting hardware in the airframe rather than replace model-specific retainers.

Installation steps: check that the collar slides onto your shaft and aligns with adjacent components, position it, and secure using the retention method present on your helicopter (set screw, retaining clip or an existing collar). After installation verify rotational freedom and minimal axial movement prior to flight.

For tuning use the collar to tweak servo-to-rotor geometry and to lock axial positions after linkages and rotorheads are trimmed. Always conduct bench tests at low throttle and ensure there is no interference with blades, swashplate, or control linkages.

Note: this is an accessory for RC helicopter models and not intended for full-size or commercial applications.