The Rot Doctor


Subject: Wood rot on boats (glycols & CPES)
Date: Wed, 18 Apr 2001

Dear Sir,

Are you aware of the use of glycol antifreeze in the treatment of rot? In your opinion would this be a good pre-treatment to your products?

We are very much aware of the use of ethylene glycol as a treatment for rot. We don't like it for several reasons: 1) While it does stop the rotting process, it adds nothing in the way of strength to the wood. If the wood is at all deteriorated, then why put something on it that is only going to stop the fungi -- you're still left with deteriorated wood. Our CPES (Clear Penetrating Epoxy Sealer) will also stop the rotting process, and additionally it restores strength to the wood. 2) All glycols eventually will leach away with moisture exposure. CPES is an epoxy and bonds "forever" with the wood. 3) Glycols penetrate the wood and will interfere with the ability of other chemistry, such as epoxies and polyurethanes, to bond with the wood. There is no adhesive or polymer manufacturer who will condone the treatment of wood with glycols prior to the application of the bonding material.

Don't use it. It's only advantage is that it's cheap.

In an all wood boat, need to treat parts of the mahogany hull and "allegedly" teak plywood on cabin sides. In this case would the THEA be used before the clear sealer? If this is the case wouldn't the THEA block the penetration of the sealer?

The THEA should be used for bonding by itself, and then the CPES applied for additional protection. Yes, the THEA blocks the penetration of the CPES, but the THEA is being applied to good wood and itself forms a barrier that doesn't allow the entrance of fungi or bacteria. Sometimes THEA is used on top of deteriorated wood that has been treated with CPES/L&L Resin and it bonds quite well, so the issue is not a critical one. It's just all things being equal, we prefer to have the THEA do its own thing when bonding good wood, then CPES applied afterwards.

Thank You,
Bob W.


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