Re: Marine Tex (good or bad idea)?
With all due respect 109 - I love to disagree with those who disagree - - er does that make it disagree squared? - - MarineTex is one of the "must" products every boater should have in his/her garage. It applies like putty and dries like steel. It can be used most anywhere. Keep in mind that it is not a substitute for good glass work for large areas but for this job me thinks Marine Tex is ideal.
I would use some waxz paper and cardboard to stop the MarineTex from sagging as it dries. When dry you will need a power sander or grinder to smooth it out - it is that strong.
No offense taken. MarinTex is a good product for the right applications. I said I have used it. However, the engineering specs don't lie. MarineTex has a tensile strength of 4,000 psi from their own website. Typical plain epoxy resins by themselves have a tensile strength of around 8 to 10,000 psi. Sot MarineTex has a lower tensile strength that plain old epoxy. not surprising to me though. Despite what you want to believe, marintex is not strong. The strength of a fiberglass laminate, whether epoxy/fiberglass or polyester/fiberglass comes from the matrix which includes the glass fibers. The same epoxies with fiberglass fibers can have tensile strengths to 40,000 psi, 60,000 psi or even higher if the fiber directions are carefully controlled. Epoxy by itself is also brittle. Don't believe me. Well pour an 1/8" thick layer of epoxy in a waxed cup and let it cure. Then remove this coin after full cure and throw it down on a concrete sidewalk. It will break. Layup a 1/8" thick laminate with the same epoxy and glass cloth and you won't be able to break it without using tools.
The original poster stated that the hull was worn almost all the way through. His picture I looked at looks like his description is accurate. How is this NOT structural???? We are not talking about simply being worn through the gel coat here. If it is structural, the repair MUST include glass fibers to compete the composite matrix. Even Ondarvr came to this conclusion and he is one of the most respected on this site with regard to composite repair.
Can MarinTex be used for a "permanent hull repair" as they say in their literature. Heck yes if it is the right kind of repair. I've used it to plug screw holes in fiberglass boats and a small tear in an aluminum hull and it worked great and I would consider those repairs permanent. But those repairs were not structural, they were only leak plugs. Big difference.
The are in question is right next to the bow eye. To say ther is no load there is ridiculous as there are going to be loads applied any time the winch is hooked to it. Also don't forget that this is the area where the bow stop rests on the boat. No load????????????
I stand by what I said. For this specific repair I 100% disagree that marinetex can be used alone.
