Hirobo HI2539012 M3 x 50 Shaft Screw — General Helicopter Part  [HI2539012]

Product summary and fitting notes

This Hirobo HI2539012 shaft screw is an RC-scale replacement fastener listed as a general helicopter part, supplied for common repair and maintenance tasks on model helicopters. The designation M3 x 50 identifies the thread size and nominal length used where longer shaft engagement is required.

Use this screw to secure shafts and linkages in the helicopter drivetrain; it serves a mechanical fastening role rather than an alignment or bearing function. When installing, verify thread engagement and side clearance in the neighbouring components, and apply moderate torque that matches the receiving material to avoid stripping.

For routine tuning and maintenance, check the screw for looseness after initial flights and after any hard landings. If thread locking is desired, use a low-strength threadlocker compatible with model-grade metals and allow full cure before flight operations.