Hirobo HI2521049 5 x 8 x 1.5mm Shaft Collar  [HI2521049]

Shaft Collar — 5 x 8 x 1.5mm Overview

This compact shaft collar is an RC-scale accessory intended for use in helicopter assemblies and other small rotary components. The 5 x 8 x 1.5mm measurements specify bore, outer diameter and thickness, making it useful where short axial spacing or a fixed stop on a shaft is required.

Serves as a mechanical stop and provides repeatable positioning for shafts and linkages. In assembly it helps maintain consistent stack-up between gears, bearings, spacers and rotor head parts, supporting predictable play and preload during setup.

Installation is simple: slide the collar onto the shaft at the chosen position and secure it following your model's standard method. When adjusting rotorhead geometry or setting bearing preload, use the collar as a reference and verify axial movement and clearance after final tightening.

Hobby notes: ensure the collar bore matches your shaft diameter before fitting, check mating surfaces for burrs, and re-check alignment after initial test runs. This description applies to RC-scale model use only.