u/atheistinabiblebelt

Help me understand how to repair fiberglass please

I have a 1979 sunfish that's been through it. She leaks badly and needs some work. Thankfully she already had inspection ports installed and sat in a dry garage for the last decade and is thoroughly dried. I weighed her in at 135# which by my understanding is just about perfect for a 70s sunfish hull.

I'm trying to research how to go about it but I'd really like if some of you more experienced folks could proof my understanding...

The boat definitely has some old repairs on it and I'm not sure what was used for them but it's pretty evident they've failed as there are pieces flaking/cracking off and I tested for leaks (by sailing her!). Anyway, in 30 minutes of water time she took on almost 15 cups of water.

Today I took my orbital sander with 80 grit to the hull. I did about half of the bottom, doing the edges and keel by hand. The entire bottom is scratches, gouges, and dings. Some expose the fiberglass, others are aesthetic. I sanded down as many as I could and stopped just short of going all the way through the gel coat on the worst of them. The ones that I couldn't sand out will be addressed another way.

Now I havent removed the two repairs with the failed material yet. They are in awkward places so I plan to use a Dremel to get the old material off and see what I'm working with fully.

I can partially see the damage so I'm expecting that removing the old repairs will expose more fiberglass.

So here's the plan:

  1. Completely sand the bottom with 80 grit to remove as many cosmetic imperfections as possible while simultaneously revealing any other small dings that may show up (I've found a few dime sized repairs doing this so far that failed when I contacted them).

  2. Use a Dremel/hand to remove the failed repair materials in all locations I've found.

  3. Use total boat fairing compound to repair the exposed fiberglass damages and deep gouges, sand to smooth/feather into the hull. Finish sand to 80-120 and wash in prep for gelcoat

  4. Apply 1 or more layers of waxless gelcoat to achieve full coverage. Apply another layer of waxed gelcoat.

So here are my questions...

  1. Does this sound like im on the right track?

  2. Can/should the waxless gelcoat layer be sanded between layers and/or before the waxed layer? The goal is a slippery smooth finish.

  3. Am I more likely to have success in getting that smooth finish by rolling/tipping/sanding or spraying the gelcoat?

I understand how much work this is, that is not a deterrent. This is not my first rodeo in boat restoration but it is my first fiberglass hull.

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u/atheistinabiblebelt — 8 days ago

Tested my project fish tonight, to no one's surprise, it leaks!

Tomorrow I'll do a proper leak test to find where to make the repairs.

It leaked 14 cups of water in 30 minutes lol!

u/atheistinabiblebelt — 9 days ago

Thanks to all for the transport tips yesterday!

Hull is supported in as many places as I could scrounge scrap lumber for and there are pieces of pool noodle at all contact points. Managed to make a little plank structure to strap the mast and spars to. The sail is well lashed down as well. Nothing wiggles at all, very solid. I'll be checking frequently on the drive tomorrow and once I get home I get to start the project! Can't wait for the next steps...weighing her first, then drying if needed, followed by a good leak test. Definitely some old repairs visible, the leak test will determine what steps come after with those. Then refinishing the rudder and db. I'm so excited now!

u/atheistinabiblebelt — 15 days ago

Transportation tips please

My dad gave me his old sunfish, she's a little rough and needs some tlc so cosmetic damage isn't too much of a concern. Anyway, this is the little trailer I have to haul her home, the drive is 400 miles. I've got 2x4s wedged under her so the hull can't rock at all, it feels really solid on the trailer. Anyone see any concerns?

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Also, I could strap the mast/spars down sticking out of the truck bed but would it be better to strap them along the keel of the hull? I tested it but it seems like the mast will bend. I wish the trailer was 8" wider so they'd fit next to the hull but I have about 1" between the hull and the fenders on both sides.

u/atheistinabiblebelt — 17 days ago