Hirobo HI2506065 flat washer 4.1 x 5.1 x 0.1T thin spacer for RC helicopter assemblies  [HI2506065]

Flat washer for helicopter assemblies

This Hirobo HI2506065 flat washer is an RC-scale thin spacer intended for use in helicopter and general parts assemblies. The stamped designation 4.1 x 5.1 x 0.1T describes the inner diameter, outer diameter and nominal thickness, which makes it suitable where minimal material thickness is required to adjust clearances or tweak alignment between mating components.

In practical maintenance and tuning the washer functions as a micro shim: adding or removing a single 0.1T washer can change shaft endplay, bearing preload, or gear mesh by a small but measurable amount. Because the part is a flat washer it’s best applied where uniform contact is needed across a bearing seat or fastener head to keep loads even and reduce lateral play.

Installation notes: handle the washer as an RC-scale spacing component, confirm orientation where applicable, and stack washers only when specified by the assembly tolerances. If a tighter fit is required, small incremental changes are preferred over larger thickness jumps to preserve drivetrain balance and component alignment.