The foot of the mast is frequently standing in water trapped in the mast step. If the varnish is not renewed frequently then water will penetrate the end grain and the wood will rot and split. In this case the lower 3cm of the mast has become rotten (soft and black) and has split badly. Left untreated the splits will migrate up the mast followed by the wet rot.

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The base of the mast showing split and blackened wood. The wood is soft and beyond repair. The only remedy is to cut back to sound wood and rebuild the base with Epoxy Filler

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The rotten wood was sawn off. The exposed wood was then coated with epoxy resin and immediately followed (whilst uncured) by a very stiff mixture of West Epoxy Resin 105 plus high-density filler 404. This was moulded into a rough plug to replace the wood that had been removed and left to cure. After curing, the plug was sanded to shape and, with the rest of the mast, covered with three coats of Epoxy resin (overcoating without sanding within a time limit of 12 hours between each coat). This tough inert base to the mast has effectively sealed the vulnerable end grain so that further deterioration cannot occur. The treatment is completed by sanding the Epoxy coating smooth and applying several coats of polyurethane varnish, lightly sanding between each coat. This protects the Epoxy from attack by the ultra violet component of sunlight.

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