Aluminium and carbon dinghy masts can both be highly developed racing spars, but they achieve their stiffness, weight and bend characteristics in different ways. The right choice depends on the class rules and the specific mast options approved for that boat.
Key differences
Weight distribution
Carbon construction can reduce spar weight and allows material to be placed strategically, but the actual class-approved mast should be compared rather than assuming every carbon spar is lighter.
Bend characteristics
Both aluminium section geometry and carbon laminate design are used to control fore-and-aft and sideways stiffness.
Repair approach
Damage assessment and repair methods differ between aluminium extrusions and composite spars. Do not treat one material's repair practice as suitable for the other.
Class rules
Many one-design classes tightly control mast construction, section and manufacturer options. The class rules come before personal preference.
Aluminium mast characteristics
Aluminium dinghy spars use extrusion shape, wall thickness and alloy properties to produce the required stiffness. Seldén's published aluminium section data shows that sections with similar dimensions can still have different weights and stiffness values.
Carbon mast characteristics
Carbon spars use laminate design and fibre orientation to achieve the required stiffness and bend profile. A carbon mast should be selected as a complete approved spar specification rather than by outside diameter alone.
Crew weight and mast choice
Where a class offers more than one approved mast option, crew weight can be part of the selection. The aim is to match the mast, sail and tuning range rather than simply choosing the stiffest or lightest spar.
Which should you choose?
Start with the class data and the mast options designed for the boat. If replacing an existing mast, record the current section and discuss whether the goal is like-for-like replacement or a deliberate tuning change.
Choosing between dinghy mast options?
Tell us the class, current mast, crew weight and whether you are replacing damage or changing the rig setup.