Seldén replacement sheaves for dinghy mast heels, masthead fittings, boom end fittings and sheave boxes, available in composite, Acetal and stainless steel ball bearing versions across three diameters to suit specific spar sections and fitting positions.
How to choose
Sheaves are precision components. The correct replacement must match the original in outer diameter, bore diameter and width. All sheaves in this collection are referenced to specific Seldén fitting positions like mast heel, masthead, boom outboard end or sheave box. Before ordering, identify exactly where the sheave sits in your spar and confirm the fitting it belongs to.
Material choice follows the application. Stainless steel ball bearing sheaves are the highest performance option, suited to positions where the line or wire runs frequently and friction must be kept low, such as mast heels and boom outboard ends under regular use. Composite and Acetal sheaves are lighter and suit positions where load is lower or movement less frequent, including masthead applications and boom section end fittings.
All sheaves in this collection are compatible with both line and wire ropes unless noted otherwise.
What's in this collection
The ø21/4-9 stainless steel ball bearing sheave (504-109) is used in boom outboard end fittings and sheave boxes. It can also be fitted as an upgrade in the forward position of sheaved dinghy mast heels and works with both line and wire.
The ø35/8-10 stainless steel ball bearing sheave (504-216-01) is used in mast heels, boom outboard end fittings and sheave boxes, working with both line and wire.
The ø35/8-10 composite sheave (504-362) is used in boom ends, keelboat mast heels and single-line reef systems. For dinghies it is used in boom outboard end fittings and sheave boxes, and specifically in the central aft two positions in all six-sheave mast heels and all aft positions in five-sheave versions. Works with both line and wire.
The ø28/5-8 Acetal sheave (504-363) is used primarily in masthead applications and works with both line and wire.
The ø21/4.2-9 composite sheave (504-364) is the correct replacement sheave for standard headboxes fitted to carbon S1 section and aluminium 2420 section dinghy spars.
The ø21/4.2-9 composite sheave (504-367) is used in 2420 and 2632 boom section end fittings and works with both line and wire.
