Hirobo HI2506011 RC Helicopter Flat Washer 3.5 x 9 x 1T  [HI2506011]

Flat washer for radio-controlled helicopters

This flat washer is supplied as a standalone replacement for RC helicopter assemblies, with the part code HI2506011. The stamped size 3.5 x 9 x 1T indicates the internal diameter, external diameter and thickness so it can be matched to appropriate fasteners and fittings.

In use, this washer distributes clamping force beneath screw heads or nuts and helps mitigate lateral play in linkages and rotor fittings. Choosing the right diameter and thickness helps keep clearances accurate and avoids direct metal contact that increases wear.

Fitting guidance: make sure the central hole fits the intended shaft or pin, ensure the outer diameter does not foul neighbouring components, and place the washer in the assembly stack prior to final tightening to preserve spacing. Swap out any washer that displays visible distortion, rust or reduced thickness.

Adjustment note: washers are useful as thin shims when refining blade pitch control geometry, setting rotor head preload, or removing minor endplay; selecting the correct 1T thickness can tighten controls without changing permanent hardware.