Re: 1985 Ebbtide Montego project
Sooo, I guess you must have some sentimental attachment to the boat????
Water being absorbed through the gelcoat and fiberglass laminates in the hull causes blisters (Boat Pox). Gelcoat is not impervious to water, it will over time allow water to be absorbed through the gelcoat. The water absorbed reacts with the resins, which build up residues and finally raise blisters by increased pressure on voids between the laminate and the gelcoat when it was layed up at the factory. This is what you see on the hull. It occurs when boats are left in the water for long periods of time and happens more frequently in fresh water. Your first step is to open up the blisters to allow them to "bleed" the excess water. I'd recommend a Dremmel for this. Take a pocket knife or a sharp chisel to start the opening of each of the blisters and weeping areas and then grind down to solid laminate. Be warned they can Stink like the dickens. Once all the blisters have been ground to solid laminate and the entire void exposed, allow the hull to dry for as long as possible. This may require a month or two or more. You can help speed this up using a heat gun but don't ove do it and get the area to hot. Fans and heat lamps help too. Depending on how long they've been there will determine how long it take em to dry.
A good technique to test the hull for dryness is to tape a clear plastic sheet, about one foot by one foot, over the clean hull surface. Make sure all the edges are sealed with tape and adhere to the hull. After 24 hours, check to see if there is any condensation under the plastic. If not, you're good to go. Once everything is dry, you can grind and feather, lay some CSM and do the standard Gelcoat repair.
As for the major damage you will have to grind back the glass 6 " along the crack on both sides and feather it down to a razors edge in the center both inside and outside of the boat. I'd also recommend attempting to compress the crack back into place a bit. You will then lay alternating patches of CSM and 1708 Biaxial Cloth to build it back up to its original thicknes. Being on the Edge of the hull complicates it some because it has to be fair on the bottom or it can cause issues with the performance of the boat.
As EZ and I both stated, it really might be time to look for another boat.
Also, when working inside the boat, with no stringers or foam, should I use plywood to distribute my weight? Can the hull support 200+ Lbs?
