Is CPES the answer

[TomMcKinney]

I recently acquired a sabot (So Cal's answer to the Optimist pram) that has a small area of softness in the topsides about 2 inches by 2 inches right at the rail. Rather than cutting it out and patching the plywood- not sure I have the skill) I was thinking of using CPES to harden it up. The product supposedly makes rotted wood strong again. The boat will then be glassed inside and out 3oz fabric set in epoxy) and then painted.

Boat is stiff, straight and fair, but currently ugly as almost all the a paint is peeling off her plywood sides, hopeflly a diamond in the rough. I was thinking of building a pram, and doubt I could do as good a building job so the $150 price tag seemed good.

Any thoughts or comments on the CPES solution?
Thanks

[Wild Wassa]

I've lost a race in a performance dinghy to a little Sabot, in an open handicap. The two boats that I keep my eye on in open handicaps, are Sabots and Mirrors. I've seen sailors in hot expensive Olympic Class boats, say, "who won?, a Sabot?, again?"

Warren.

[ 01-11-2004, 09:43 PM: Message edited by: Wild Wassa ]

[JimD]

Never used the stuff, Tom, but I doubt its a very practical solution for your problem. I had a few inches of rot on a plywood kayay a couple years ago, cut it out and replaced it with new wood. Now the patch is the best part of the boat smile.gif

[Wild Wassa]

The way CPES works is that it chases into the area where rot is and into those areas where the tendrils of the fungus will advance to, and starves the rot. CPES forms an epoxy matrix, and stops the advancement of the rot. CPES is not glue, it is a very thin epoxy, the solvents are xylene and toluylene. The solvents evaporate leaving a porus matrix. It soaks into rotten timber (that which you can't remove) as if you had soaked the area in water. Remove all soft rotten timber before applying CPES, I should say remove all that you can. If you miss some, tough, CPES will get it.

I observe, that spongy areas become hard and brittle, which means every aspect of the rotten loose material has been coated with the CPES. Again from what I've observed, the epoxy that I've applied, after CPES'ing, disappeared into the previously rotten areas, not just under the delaminating ply faces, but into the sponge. I found that I ended up with blocks of epoxy, in the voids. That were previously spongy.

This is how I would tackle the problem. I'd put a circular wire brush in a drill and like a dentist, remove all rot. Then paint the CPES on or form a reservoir (preferred) and fill with CPES. Allow to cure following the manufacturer's recommendations. Essential for the evaporation of the solvents.

I'd then paint on a thinned epoxy (thinned using a denatured alcohol, BoatCraft Pacific users, only thin with a TPRDA, denatured alcohol is not a reactive agent with BC P's epoxy and will only weaken their epoxy), and allow this to cure. Next, followed by a 'normal' epoxy, and allow to cure. Finally, I'd fill the remaining void with an epoxy with a compression strength filler added, or Smith and Co's compression strength filler, Fill-It, if still needed. The resulting area will be stronger than the wood it has replaced, ... if that wood was good.

Warren.

ps, Is CPES the answer? I'm waiting for something better too, along these lines,... but I'll use CPES until then.

[ 01-11-2004, 09:46 PM: Message edited by: Wild Wassa ]