Fiberglass delamination or hydrolysis or what?

[Tuxie]

I had pretty eventful solo sail that lasted few nights last summer. I had (unforecasted) crazy 2-3 meter waves for 12-16 hours of the trip. My bow was crashing through the waves and eventually my anchor worked itself loose and banged the bow for quite a while until I heard and realized what was happening. And yepp I definately need better system to hold my anchor...

Anyways initially the damage did not look that bad but when inspecting closer I found out that there was an old repair job in the bow. Today I got some photos from the fiberglass guys after they had been grinding the fiberglass to open it up. They also said that some of the old fixes had been just done with gelcoat alone.

To me that does not look healthy laminate and there seems to be surprising amount of delamination going on.
I'd appreciate any hints and comments on how to continue with the repair? To me it seems a lot more of the laminate needs to be removed to get to healthy fiberglass and then fix it properly after that. I'm just surprised how much delamination there is...

Could this happen by just moisture ingress into the laminate and over the years moisture would have delaminated the lamimnate?

[Pete7]

I would suggest someone in the past has crunched a pontoon going a bit too fast.

A nice piece of curved stainless steel would cover the repair and prevent future anchor rash.

Will the anchor go in the anchor locker? one of the reasons we keep ours there.

Pete

[Benz]

Looks like fiberglass that's been whanged on a whole lot. That separation into plates is common with that sort of injury. I'd be inclined to grind a bigger area so I could scarph bigger patches in there without getting a bulge, though Pete's idea is good, especially with such fine bows.
It's going to be an expensive thing to fix so it looks good: sorry it happened to you.

[wingssail]

Originally Posted by Benz

Looks like fiberglass that's been whanged on a whole lot. That separation into plates is common with that sort of injury. I'd be inclined to grind a bigger area so I could scarph bigger patches in there without getting a bulge, though Pete's idea is good, especially with such fine bows.
It's going to be an expensive thing to fix so it looks good: sorry it happened to you.

No, I disagree that this is going to be expensive or even complicated.

You can do this yourself.

Grind it back to a slightly bigger area than is showing with gently tapered sides.

Lay up with mat or roving layers and epoxy until it is generally flush, but not quite. Use small pieces first. Fair it with thickened epoxy (or even polyester filler, if you must) then sand as smooth as you can and hire a painter to match the gel coat.

She'll be right mate.

[guyrj33]

Originally Posted by wingssail

No, I disagree that this is going to be expensive or even complicated.

You can do this yourself.

Grind it back to a slightly bigger area than is showing with gently tapered sides.

Lay up with mat or roving layers and epoxy until it is generally flush, but not quite. Use small pieces first. Fair it with thickened epoxy (or even polyester filler, if you must) then sand as smooth as you can and hire a painter to match the gel coat.

She'll be right mate.

Gel coat is as easy to apply as paint and it's more durable. There is probably a specific protocol to follow when applying gel coat over epoxy.

[C420sailor]

Just let the epoxy cure fully, then give it a good washdown with warm water to get rid of the amine blush. Sand, then wash down again. Then gelcoat to your heart’s content.

Matching isn’t bad either. Just takes patience, trial and error. Start with far less pigment than you think and you’ll be fine. Get the color nailed, THEN add the MEK.

This isn’t a hard repair, and I’m slightly above a novice.

[CF32907]

CaptVR here,
Here's your story. An anchor did not cause the delam problem, my guess would be a concrete dock that someone hit years ago, done a partial repair and lots of gelcoat. The delam was from a cold joint from the factory where they stopped layups for the day and finished off in the morning. Normally the cold joint won't effect much unless you hit something solid. After building six boats and inspecting 1000's over 60 years, don't worry about it, just don't hit anything really hard and stationary.
Your cutouts and tapers look good, I would probably make them a bit larger by a little shallower taper. This will spread any future loading over a bit more area and reduce pressure point impact to lessen chance of more damage. I would use alternating layers of mat and roving. Definitely use epoxy. Definitely sand epoxy so no glossy spots are seen, this also gives some tooth so gelcoat will stick. Give it a couple days to gas off before doing gelcoat. You can do your own gelcoat with a 4 - 5" roller. After curing, long board and polish as needed.
Doing damage surveys for 55 years, I would bet a good 30% of the boats out there have some delam, some where in them. Some from manufacturer, some from grounding, some from lighting, etc. Most owners will never know until something like this happens.
At any rate, simple fix, make it look perfect, and some jerky surveyor like me will never know it happened. Hope I relieved some of your anxiety, take a deep breath and relax.
Happy sailing to all. Capt Vince Rakstis, Ret.MS

[C420sailor]

Is there epoxy friendly CSM?

[Benz]

Originally Posted by C420sailor

Is there epoxy friendly CSM?

CSM will eventually soak up epoxy, but you have to give it time.
I would do the repair with vinylester, a layer of CSM to start with, then some 1708, finished with two plies of 10oz boat cloth.
Fair with vinylester fairing compound (essentially marine Bondo, catalized the same way), then gelcoat.
It's expensive in that matching gelcoat requires skill and patience that if you don't have, you'll have to pay for.
It's not a hard repair for someone who knows their stuff--but folk who know their stuff don't work cheap.

[Spot]

Make sure it's MEKP and not MEK for polyester and vinylester resin.
You want the peroxide, not the paint stripper...

[Tuxie]

Thanks for the ideas all. I agree the repair is not that hard to do, the main problem is that there are few thousand kilometers between me and the boat right now and when I finally get to the boat I need to get it on water pretty quick. Hence I have a local fiberglass guy working on it. Just need to make sure he takes the right steps. Also the price didn't sound too bad.. Closer to 600€ for the project.

Also good to hear about others thinking that more sanding/grinding needs to be done. I wasn't sure if I was a bit too sensitive about those flaky layers but sounds like I had roughly the right idea.

[nortonscove]

That's definitely the result of impact. Any delam is the result of impact. The stress would be from the forestay and therefore at the furthest point forward. I would grind until there was no delam and then build up. A little more extended bevel might be required. A piece of stainless wrapped around there as recommended previously would be advisable.