Hirobo HI2521112 Collar 3 x 5 x 11 RC shaft collar  [HI2521112]

Product overview

This is a small-scale RC shaft collar listed as HI2521112 from Hirobo, specified by its 3 x 5 x 11 dimension. The part functions as a locating and retaining collar for rotating shafts and small assemblies found in helicopter hardware, providing a straightforward mechanical stop or clamp point without altering primary components.

The collar's role is primarily positional: it secures shaft position, limits axial play, and helps keep linked components such as small gear stacks or bearing seats aligned. Because this item is a basic mechanical accessory, installers typically evaluate fit by comparing inner bore and axial length with the target shaft and adjacent parts before final assembly.

Installation notes: slide the collar onto the shaft to the required position, confirm alignment with mating parts, then apply the existing set screw or clamping method used on the model. For repeatable results, mark the shaft location and verify rotation clearance after tightening. During tuning, small adjustments to collar position can help fine-tune gear mesh or blade tracking without modifying larger components.