How did you get inside there? Is the already an inspection port or do you have an endoscope? If it’s the former, then see response #1 above. If it’s the latter, then install inspection port and then seeFriend gave me a sunfish, said it leaked a bit. Took it out yesterday and noticed water draining from the bottom when the boat was back on the boat lift. Inspection revealed the hull was half full of water. Inspecting it I see a hull gap right in front of the centerboard and about a 1/4 inch hole clean through. Looks like the patch from an earlier repair came out. This is just a fun boat so a perfectly faired hull repair is not needed however I have not done any fiberglass work and would like advice on what to get; how to do it, and particular advice on the location since it is so close to the centerboard trunk and widening the hole needs care. Thanks in advance
many thanks to all for the tips -Easy fix. Photos look like the damage extends to the trunk interior. This is a common oops from grounding the board at speed.
REF Below is taken from a previous post of mine.
Your port give you excellent access to lay up a proper glass-epoxy patch and reinforcement.
use painter tape all around the openings to keep the epoxy off the hull
scarify the interior to get a good bond.
I use only US Composite 635 THIN resin. On line purchase. Buy the dispensing/measuring pumps. Excellent wet-out, slow cure, long working time, zero blush so multiple layers are easy. soap and scrub clean up but wear gloves. I get 9 mill pro gloves at Harbor Freight, durable and affordable.
for your repair I would apply serious layers inside and a pretty large area. Use a 1” throw away chip brush for mixing and applying. Use the brush to smooth out the patch and to exclude the air. Pre-wet the surface before the first layer. Pre-cut all planned patches before starting.
when the inside is done, flip the hull, grind a tapered depth into the broken old fibers maybe 2 inches either side of the crack. Fill with glass mat and epoxy. You can promote a smooth finish by pressing a thin polyethylene film sheet onto the surface. Stretch the film flat and painter tape the edges to make the film stay flat. If you do this carefully the surface will be nearly glossy when the film is pulled and near net shape. Work the air out. Later, If you need fairing, mix in 3-M micro balloons from US Composites to a stiff creamy consistency. Easy to long-board.
cure time on the resin is 2-3 days for sanding. I said it was slow. Working time is 2-6 hours depending on temperature.
I checked out the US Composites site for the resin you posted and that site looks great - I see they have both fiberglass cloth and fiberglass mat. Any downside to using the cloth rather than mat? the cloth looks like it may be easier to work with (saw a video of a repair with mat and it seemed harder to cut and handle).Get a SMALL right angle grinder and use the overlapping flap wheel. There are very affordable grinders at Harbor Freight.
I would cut strips of glass. Start by laying them against the hull and up the trunk. Strips around 1-2” wide are easy to form on curved surfaces. Us the packs of woven glass found at hardware stores such as Home Depot. Use the bent SS medical scissors for cutting. These are excellent with the single serrated edge. Wrap the next layer of strips around the trunk overlapping the flat sides by 5 inches. If usually have trouble making them stay in contact then cut polyethylene film to wrap and cover the entire wet work. Use long strips of painter tape to hold it tightly in place. Next layer is large pre-cut patches against the hull and cut out around the trunk. These several layers should all be progressively larger as they extend into the flat of the hull. Repeat the process until you are satisfied with the thickness and integrity, about 3/16 inch, 4-5 layers.
I also use a Harbor Freight high speed die grinder and carbide burrs for detailed cutting and fairing. I don’t think you need this unless you are a tool hound. The deck joint is a possibility as well but the trunk needs fixing. There is a tutorial with photos on this site for how to attack the deck joint. Basically, drill out the pop rivets and remove the aluminum trim. Spread the joint and clean. Apply suitable replacement bonding material. I’d use 3-M 5200. Permanent and flexible. Wear throw away clothing and gloves.