The Rot Doctor


Subject: Dry Rot In Mahogany Keelson
Date: Thu, 06 Feb 2003

I have a 17' Thistle sailboat constructed entirely of mahogany and built around 1960. The hull is 5-ply mahogany while all structural members are solid mahogany. I recently discovered some dry rot on the interior keelson near the centerboard trunk. The boat is well restored and does not leak. On the exterior below the waterline is an epoxy over fiberglass system which has been painted with 2-part epoxy paint. On the interior keelson is West System and varnish. There is also a fillet joining the centerboard trunk. The entire boat is finished bright with 12 coats of Epifanes varnish. Prior to visiting your webpage I would remove all the dry-rot until I reached competent material, rebuild with mahogany and West System. How would your CPES product be applied here? Does all the dry-rot still need to be removed? What will the color/appearance be since the rest of the boat is bright?

Thanks in advance for any assistance you can offer.

Mike R

Unlike the West system repair, with CPES it is not necessary to remove the rotted wood if you don't want to. It does need to be dry, and thoroughly soaked with the CPES. Any missing wood does need to be filled in with a thicker epoxy.

Typically we remove all the loose crumbly rot and saturate the rest with CPES. To treat in place you brush the CPES onto thinner rot (1" deep or less), and drill holes in the wood to saturate deeper rot. Finished bright, the repair will be visible. How visible is dependent on how rotted the wood was, how much filler might be used to fill any voids, etc. The best way to get a close cosmetic match would be to scarf in a veneer piece of closely matching wood. Done carefully, with thin sawtooth fingers where end grain meets, the repair is invisible to all but the closest inspection.

Please let me know if you have any further questions.