Hirobo HI2521075 Collar 3 x 7 x 7 - Shaft Locator for Hirobo Models  [HI2521075]

Notes for rotorhead and linkage setup

Listed among general Hirobo helicopter parts, this small collar functions as a shaft locating and retention component on model rotorcraft. The 3 x 7 x 7 figure in the name indicates the collar sizing used to determine suitability for a given shaft or linkage interface.

In everyday use the collar is a compact method to hold axial position of shafts and linkages while you adjust geometry or perform balancing. Installation normally uses the model's existing clamp or fastener arrangement; always check axial clearance and alignment before making the fit permanent to avoid binding or slop.

For tuning purposes the collar can act as a mechanical stop or spacer to help achieve repeatable blade pitch settings, swash alignment, and rotor head indexing when used together with the model's original hardware. Keep the area free from debris and monitor wear to ensure reliable results.