Hirobo HI2521144 Collar 2.6 x 3 x 2.9 for Shaft Alignment  [HI2521144]

Precision collar for rotor shaft alignment

This collar is an RC-scale replacement part intended for use in Hirobo helicopter general parts assemblies. It functions as a locating and retention component where tight dimensional fit is required along shafts or inside hubs. Consider this item a small mechanical spacer used during assembly and setup rather than a primary load-bearing member.

Fitting is straightforward for hobby technicians experienced with rotor-head and tail-rotor subassemblies: slide the collar into its seat on the shaft or into the mating bore, check axial alignment, and then tighten the surrounding fasteners following the original equipment practice. After installation, confirm free rotation and verify endplay to ensure the collar is seated correctly.

During rotor tuning, this collar helps keep shaft position consistent which supports trim repeatability and easier part interchange. As with all RC helicopter servicing, inspect fit before flight and check the collar regularly for wear during routine maintenance.