Composite Materials/rudder/keel ?


Can you explain the construction of the boat to keel, and rudder?

hi Roy,
on pleasure craft, rudders are usually made of a fibre glass skin over a foam core, which in turn is around the main steel or chrome-moly shaft.  on race boats, the rudder is sometimes solid composite, typically carbon fibre, made in carefully CAD-CAM conditions.  on much older boats, the ruder is sometimes wooden, but can include a structural shaft (much like an aircraft spar Roy).

keels are different again, sometimes the boat is completely finished, then the keel through-bolted and faired in.  sometimes, especially when steel or tungsten is used, the boat is manufactured with the keel hollow, then later filled.  Most boats that I have worked on have lead keels cast separately, then attached to the hull.

I hope this helps,

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andy mackay


Composite fabrication and testing, plug and mould design & build, surfacing materials, gelcoats, resins (epoxy, polyester, BMI, urethane) GRP, FRP, carbon, aircraft and marine composites, infusion techniques, Light RTM methodology, troubleshooting materials and process engineering.


11 yrs experience with aeronautical, marine and bathroomware composites.

Royal New Zealand Air Force Advanced Composites Course BCA Victoria University, Wellington, 1995

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Aeronautical, marine and bathroom ware composite cmanufacturing.

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