The Rot Doctor


Date: Fri, 28 Mar 2003
Subject: CPES question (on an RV)

Attached are some pics of the window. I took off part of the window frame to see under the fabric, and it was still wet from the last rain. It is really gross crumbling wood- no structure to it at all for about 2" in from the window, up the side along the window for about 12" and around the top of the underside for about 3". The wood appears to be about 3/8" thick, but its hard to tell with the expansion of it. I need to get another wrench to get the rest of the frame off before I can get the upholstery pulled back. Can you tell anything from these photos??
Julie B.


What you are seeing is fairly typical, and thanks for sending the jpeg images.

To repair you're going to have to allow the wood to become reasonably dry (this may take a little time) and then once dried you will have to saturate it with our CPES (Clear Penetrating Epoxy Sealer). This will stop the rotting/delamination process completely, and harden some of the loose wood. CPES can be applied by brush or spray (using an insecticide spray bottle -- we sell them or you can get your own).

After about a week (keeping everything dry), you will start pumping in a soft mix of our Layup & Laminating Resin and sawdust. This is a mix you make yourself by first mixing the L&L Resin, and then adding sawdust until you get the consistency you want. If it's fairly soft, it will tend to flow down into the vacant areas; if it's thicker it will hang. You may want a soft mix for the lower areas and a stiffer mix for the overhead areas. The L&L Resin mix will bond with the CPES-treated wood and make a structural repair. It will cure hard in 24 hours. You can finish off the surface next to the framing with a stiff, bladeable mix of the resin/sawdust combination.

We do sell empty 10 oz caulking tubes (3 for $6.95) that you can use in a standard caulking gun if you think these would be helpful.

The L&L Resin/sawdust mix is almost as hard as steel when it is cured, so make the finish as smooth as possible. If you need to drill into it, serial a pilot hole first.

What will you need? I would estimate a 2-quart unit of the CPES, and probably a 2-quart unit of the L&L Resin. If you need sawdust, I'd suggest our 5# bag, but you can use your own sawdust.

Okay? And feel free to come back if you have additional questions.


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