Carbon fiber and other questions.

[Serpent67]

Hi all. I have a had a boat for a couple years now. It was a gen I got off CL for a good deal, but because of work I shelved it and just getting to mess with it now. The previous owner had upgraded it some and it moves pretty good on 6s. I dinged the front left point up shoring it and would like to fix it. What would be a good fiberglass filler to do that? It also has a couple little chips here and there that need attention. I figured since I was doing that, I would just go all out and makeover the whole cat. When laying carbon in the bottom, how many layers are used to stiffen the hull and how far in, and up the sides? Also, what resins? I've never done stuff like this before. Any other upgrades to the hull you all could suggest, I am all ears. I want to get this boat as good as can be and then get a empty mono hull and build one of those from scratch. I'm pretty good at stuff once I know what to do. Thanks for any info.

[Heath M]

I recently took the tip of my Carbon fiber mono, lucky for me it was a solid tip so I just used Builders bog to fill it in and reshape it. Has held up well since.
Normally 1 layer of CF is good enough to stiffen the hull and most the guys on your side of the world use West Systems laminating epoxy. There are some good threads around on how to lay up a hull, just do a search.
Good luck and don't forget to post pics :)

[Serpent67]

Thank you Heath.

[lt130th]

For filling deep gouges in fiberglass you may want to use an epoxy with fiberglass filler (chopped up fiberglass cloth or microbeads). If the gouge is only through the gel coat (which is an epoxy), you can fill that with a $20 bathtub repair kit from Lowes/Home Depot. Doing a fiber composite layup on the interior of the hull is open to whatever you have the means and patience for. You can do a few layers of fiberglass cloth and basic slow-setting epoxy/resin for just building up the strength. On the other hand, you can do a single layer of carbon fiber (3k-12k & whatever weave you want, depending on how much patience you have to work with the varying stiffness) or carbon Kevlar cloth, and something like West Systems 105/207 epoxy/resin for a strong, aesthetically pleasing finish. My approach to an inlay is to cover as much of the interior as I can reach because it serves a couple of purposes. The first thing it gives you is rigidity/stability. The second thing is sort of uniting the upper and lower hull halves, and preventing the seam from separating in a high-speed flip. The third thing, is supporting the deck around the opening of the canopy. So I try to run the carbon fiber all the way up the walls of the sponsons and up under the deck around the hatch opening. I flipped a Pro Boat Miss Geico 29 on its way through the 60 mph range and the results showed exactly what I'm talking about.

134408134409134410134411134412

That crack is where the air pressure inside the hull blew out the seam when the boat hit the water after airing itself out. The crack stops right at the carbon fiber layup, inside. I can still repair that hull, but who knows how much worse the damage would have been without the carbon fiber layer bonded to the interior.

Michael P.