Hi,

In my opinion, it is worth fixing if you are doing it for yourself as a personal project, and you can make use of the boat. If it was my project, I would proceed as follows.

Use only epoxy and glass cloth for the structural work, and epoxy gipe for fairing - it bonds much better than polyester. Do the structural stuff inside where possible, but if an inside repair is not feasible, an outside one will be equally strong, you will just have to spend a bit more effort fairing it before painting. I would not separate the hull and deck, it should not be necessary. If the kevlar cloth is bent and delaminated but not ripped at the damage, the patching will be stronger than it would otherwise. When you are doing the repair, take care to work epoxy well into any delaminated kevlar cloth before covering it with glass cloth. Doing this will recover at least a bit of the stiffness and strength of the original layup. Do not try to grind through the kevlar in an attempt to feather repair edges, you will just make a mess as the kevlar is nearly grind proof.

You do not have to apply huge amounts of glass to effect a sufficient repair. Keep in mind that the original layup is quite thin, and this means that your glass cloth patch does not need to be very wide to obtain sufficient strength. Also, in its thickest part, the patch does not need to be much thicker than the original laminate. Maybe a bit thicker since the original is Kevlar, but not much. At the standard ratio of ~12:1, your patch would only extend about an inch on either side of the damage. Since the laminate is thin, you can go wider than that, but there is no need to pile on glass six inches from your damage. If it was me, I would taper my glass application out to a maximum of about 3" from the damage, and at that distance there would only be the last single layer of glass. I would start the initial glass strip at about 1"or so wide, and feather them out from there to end up with the number of layers you want by the time the repair edge is about 3" from the damage. As mentioned earlier, check out the repair instructions put out by West System., the web address of the pdf is shown below.

I think that you should end up with a boat that is only a few pounds heavier than the original, certainly still lighter than the glass composite version of the same design. If you do the job properly with careful surface prep under the reinforcements, the boat will be more or less as strong as the original was. As others suggested, I would paint the exterior, not gel coat it. If you want it to look spiffy, you could use two part polyurethane, in which case, how it looks will depend on your fairing efforts. If you just want it to paddle, use whatever you like to protect the external epoxy fairing from UV.

Let us know how you make out.

Cheers,

Allan Edie

http://www.westsystem.com/ss/assets/HowTo-Publications/Fiberglass-Boat-Repair-and-Maintenance.pdf