The Rot Doctor


Subject: Wooden Spars and Teak Decks Restoration
Date: Tue, 06 Apr 1999

I have recently purchased a 1972 Cheoy Lee Offshore 33 as a project boat. I am having a hard time finding info on wooden spar care and maintenance. The mainmast was painted before and about half has peeled off. I believe it is made of sitka spruce. The mast also has some natural cracks. Should these cracks be filled and with what? Any other care suggestion are welcomed.

I assume that the natural cracks are fairly narrow, which is usual. I'd suggest pulling the mast, stripping it down to bare wood, giving it one coating of CPES (Clear Penetrating Epoxy Sealer), and then building up from there with a polyurethane marine varnish (which will have UV filters in it). I would apply at least 5 coats of the varnish, and 7 or 8 would be better.

This will protect your mast. The varnish and the CPES, being clear, will also allow you to keep your eye on the wood through the years and if you see darkening or discoloring later then you will know immediately that the area needs attention.

If the cracks are narrow and just natural wood shrinkage then I wouldn't worry about them. The CPES and the varnish will protect the wood inside.

Several of the teak deck planks are missing screws or some of the screws have pulled out of the fiberglass underdecking. What would be the best repair for this? I have heard of removing only the plank that are loose and covering the fiberglass with an epoxy and graphite. Then lay the planks in the wet epoxy mix as a bedding and not to use the screws other then some for temporary clamps. After curing remove the clamp screws and fill their holes with the epoxy and graphite mixture.
I am questioning the long term effects of this method.
Any help or advice you could give I would appreciate.


If only the screws are missing and otherwise the teak decking is okay, then I wouldn't mess with removing planks and re-bedding. It's a major hassle and not a solution anyone takes unless absolutely necessary. You could insert new screws and bung them over, using, if necessary, an all wood glue such as ours. Check the integrity of the fiberglass/core that the screws are going into. Loose/missing screws could be a sign of substrate deterioration.

The epoxy and graphite method is one I believe is suggested by West Systems, and so it probably works. You'd have to be absolutely sure that the glass sub-deck is very clean and dry, and roughed up a bit to give the epoxy something to grip. The alternative method is to re-bed in something like 3-M's 4200 or 5200 and then re-caulk with Thiokol or a similar bedding compound. Also a hassle. Don't mess with the deck planks unless you absolutely MUST!

Come back if you have more questions.