The Rot Doctor


Subject: Ant damage to a bulkhead
Date: Mon, 11 Jan 1999

I have a 43' Egg Harbor sportfishing boat that has had ant damage to the top portion of the aft engine room bulkhead. I have gotten rid of the ants but need to repair the bulkhead. I have access to the bulkhead all along the top of the bulkhead and thought I would just pour an epoxy product into the plywood from the top and let it flow downward through the ant trails into the damaged area. The sides of the bulkhead are intact as the ants had just eaten out the center portion. I'd appreciate any thoughts as to whether this is a good idea and a recommendation as to product if you think it will work. By the way, I got rid of the ants by pouring cuprinol into the bulkhead to prevent the possibility of future rot and to kill the ants. It is dried out by now but I thought I'd mention it in case it made a difference. Thanks!!!

Ants! As if boat owners didn't have enough to think about....

Your plan is a good one, although the Cuprinol will retard the absorption of the epoxy into the wood, since it is a petroleum-based product. Still, you should treat additionally with an epoxy, because over time the Cuprinol will oxidize away and leave the wood vulnerable to ant re-infestation, not to mention rot fungi.

The best plan would be to use our Clear Penetrating Epoxy Sealer (CPES) as the initial treatment, applying it generously to the top edge and allowing it to be absorbed into the ply and any ant tunnels. The mixed CPES is about the consistency of diesel fuel, is slow setting and so it will penetrate a long way. Allow about a week for the carrier solvent fumes to evaporate away and the epoxy to set. If in an enclosed environment and without good cross ventilation, we suggest the use of a face mask capable of filtering organic fumes. A 2-quart unit would probably be sufficient, although end-grain ply will sometimes absorb a lot. It will only do the wood good.

Following that, I would suggest that you drip in our Layup & Laminating Resin, which is also a 1:1 mix, slow-setting and will have time to settle into the ant tunnels. It has a 24 hour hard-cure time. This is a tedious process. We drip off a thin stick, keeping handy a rag and a can of epoxy solvent for wipe-ups. Other people will use cooking basters to flow in the resin. No mask needed here. It will be difficult to fill the tunnels to the top, because the resin just keeps settling into the hollows of the ply. Still, it will plug a lot of the inside tunnels and coat everything with a hard epoxy shell. You could finish off the tunnel entrances with a few dabs of the Epoxy Filler, which becomes hard and dries just off-white, also within 24 hours.

Come back if you have additional questions.