Busted fiberglass on deck

[Kuncicky]

Moving right along with trying to get my new old used boat back in some sort of shape, I notice that under the carpet on the deck there is some busted fiberglass. Looks like maybe something really heavy dropped on it at some point in the past. Not noticeable under the carpet, and doesn't give when you walk on it. But when you pick the carpet up it looks like jigsaw pieces which have put together.


My inclination is to just take the pieces up, spread some fiberglass resin with hardener on the deck, and put the pieces back down in it. And after a few days of curing, a light coat of resin and hardener brushed on top of the pieces.


Any thoughts? Comments? Criticisisms?


Thanks,
Bill

 

[STB]

Can you post a picture.?

The fibers of fiberglass usually interlock so the broken edge more often looks like the ragged edge of torn cloth than jigsaw pieces, at least if it breaks vs being cut.

I'm wondering if it might be a different substrate?

 

[Kuncicky]

Can you post a picture.?

The fibers of fiberglass usually interlock so the broken edge more often looks like the ragged edge of torn cloth than jigsaw pieces, at least if it breaks vs being cut.

I'm wondering if it might be a different substrate?

I think you are probably correct. After giving some thought to it, I think it would probably be the gelcoat rather than the underlying fiberglass. The original question is still the same, though -- is my suggested method for repairing it feasible?


Bill

 

[STB]

Can you post a photo?

In general, when one has bad gelcoat, the usual fix is to sand it down until down to a good substrate and then prime and paint, using a high-build primer, multiple coats of primer, or some thickened epoxy or other filter to fill and smooth, sanding as appropriate. There is little value yo gluing in old gelcoat.

But, I'd still really like a picture, or we could be talking about very different things.

 

[Kuncicky]

Can you post a photo?

In general, when one has bad gelcoat, the usual fix is to sand it down until down to a good substrate and then prime and paint, using a high-build primer, multiple coats of primer, or some thickened epoxy or other filter to fill and smooth, sanding as appropriate. There is little value yo gluing in old gelcoat.

But, I'd still really like a picture, or we could be talking about very different things.

I'll take a picture when I go down there Monday. I am up in Georgia, and the boat is at the dock of a friend down in Florida.



Bill

 

[FF]

"is my suggested method for repairing it feasible?"

Not if the deck is damaged. Resin has almost no strength , GRP is GLASS reinforced resin, not resin alone.

A simple but not attractive would be a few layers of glass in epoxy resin and leave the rug over it.

The damaged surface will need to be ground clean for even epoxy to stick.

 

[SoWhat]

I grind out all cracks with a dremel. Apply epoxy resin with filler. Sand and fair. finish with gelcoat. But you imply that pieces are loose which would suggest delamination. That would require a different approach. Yes to the photos.

 

[Alisske]

Just to jump in, i think folks don’t want to give answers is that they don’t want to give wrong advice.

Fiberglass repair is a “tricky beast” and details mean everything (hence why everyone wants a photo)

If its just gelcoat spider cracks, no structural damage, and does not leak,, then you would be amazed at the time and expense to fix something that is lore or less cosmetic. It actually as much work as damage that penetrates lol.

Once you post a pic, you will get a flood of responses, mostly good ones, lol

 

[Kuncicky]

"is my suggested method for repairing it feasible?"

Not if the deck is damaged. Resin has almost no strength , GRP is GLASS reinforced resin, not resin alone.

A simple but not attractive would be a few layers of glass in epoxy resin and leave the rug over it.

The damaged surface will need to be ground clean for even epoxy to stick.

The few layers of fiber in epoxy resin sounds like an excellent idea. I am not particularly worried about how attractive it is. As you say, just keep it covered. Plus she is an old lady anyway, and is always going to look like an old lady, no matter how much makeup is applied.


Sorry for the promised photos not yet appearing. Tropical Storm Claudette has brought a lot of rain to this area, and so I have not yet been able to drive down to the coast. Thunderstorms every single day.

 

[Comodave]

If you are not concerned about it looking good but just want structural integrity then it is pretty easy to do. I would grind out any damaged glass until you get to solid glass. Then lay in some 1708 glass, as many layers as needed, with epoxy resin, it is stronger. Then after you get it built back up almost level with the surface use some thickened epoxy to use as filler and make it smooth. Then paint it because epoxy isn’t UV stabilized usually. Done. Depending on how big an area it could be done in a couple of hours. I use Roloc sanding disks in a 90degree drill to grind out the old glass. But you could use other sanding methods. The 30 something grit Rolocs work pretty fast..

 

[Kuncicky]

Can you post a picture.?

Well, sigh, the situation is not what I thought it was. It is worse. I thought it was just the one spot on the deck. But I went down today, to get the photo, and did some more looking around. And there are lots of places on the deck which are like the photo. Cracked and crazed. So my thought about filling in the bad area with glass and resin won't work. I think now that the best thing to do would be to just sand it down and paint it. The areas will still be there, under the paint.

 

[Toadhall]

Well, sigh, the situation is not what I thought it was. It is worse. I thought it was just the one spot on the deck. But I went down today, to get the photo, and did some more looking around. And there are lots of places on the deck which are like the photo. Cracked and crazed. So my thought about filling in the bad area with glass and resin won't work. I think now that the best thing to do would be to just sand it down and paint it. The areas will still be there, under the paint.

Kinda looks like plywood that was glassed over then panted.
If so maybe all the structural strength is still there.

If so , fair and repaint??

 

[Comodave]

I would sand it and then lay on a couple of layers of 1708 and fair it a bit then paint with Kiwigrip.

 

[STB]

That doesn't look like glass or anything structural to me. It looks like gelcoat or some other type of surface treatment is crazing badly. How thick are the pieces?

Is the deck soft, mushy, saggy, or deflected?

Comodave's suggestion is a winner in my book.

My only thinking is that more glass might be optional. If the existing glass is good, you can sand, fair and/or prime for smoothness and consistency and kiwi grip. Kiwi grip is very forgiving, so perfect you won't need to be.

But, if any of the substrate is wet, it needs to be 100% dry before putting anything down.

 

[BruceK]

Hard with a photo but it looks like a cracked extra f/g layer added on top of the deck. See how it finishes with a change of surface on the inside? If so,probably not structural.

 

[Kuncicky]

That doesn't look like glass or anything structural to me. It looks like gelcoat or some other type of surface treatment is crazing badly. How thick are the pieces?

Is the deck soft, mushy, saggy, or deflected?

Comodave's suggestion is a winner in my book.

My only thinking is that more glass might be optional. If the existing glass is good, you can sand, fair and/or prime for smoothness and consistency and kiwi grip. Kiwi grip is very forgiving, so perfect you won't need to be.

But, if any of the substrate is wet, it needs to be 100% dry before putting anything down.

It appears to me to also be gelcoat or something like that. The pieces are probably 1/4" thick or less. The deck is solid -- not soft or deflected in the least bit. I am also thinking that more glass is not necessary, because of my planned usage of the boat. Just a day-tripper, strictly coastal, and no need to take out in bad weather. So a good sanding, priming and kiwi grip sounds like the perfect solution.


Thanks, guys, for all the good advice!


Bill

 

[Turtle Blues]

Your glass /resin layer has separated from the gelcoat layer. you need to remove the gelcoat layer completely before putting another layer down. if you encapsulate the existing surface it will continue to separate. Depending on how much still adheres to the substrate you may be better off making the first pass with an electric plane. This was problematic when fire retardants were first introduced into some resins. Have seen entire hulls shaved and then re-coated to stop blistering due to this issue.
As suggested above the most forgiving surface application is probably Kiwi Grip.
If you wanted to reproduce the diamond pattern you would need to go to a hard solid color 2 part resin or gelcoat and lay and then roll the pattern mat. It is available from Flexmold in Ft. Worth TX.

 

[Alisske]

I apologize to those in advance who feel the answer is obvious, but the picture is what you found under a carpet? (You did not work to it?)

That thing looks a mess, but maybe not something that needs to be addressed ASAP if its water tight and structurally sound.

If its solid and waterproof, you may just want to enjoy the boat for a season or two, then handle when you ready to get into the “deep end” of fiberglass repair.

Its nothing major to do, but do you want the headache in the middle of summer?

Just a thought. I totally understand that you want to deal with the issue etc…. But maybe enjoy yourself a bit if its under a carpet and you can handle towards the end of the season.

 

[FF]

"The pieces are probably 1/4" thick or less."

Gelcoat is never put on that thick, it would crack.

My guess is its fairing compound from an old repair.

Fairing compound has little strength.

Grind all the old crap off and lay up epoxy and glass to make a good repair.

There would be very little extra time or expense to doing it right.

 

[slowgoesit]

Not if the deck is damaged. Resin has almost no strength , GRP is GLASS reinforced resin, not resin alone.

Not trying to be picky, but GRP is glass reinforced PLASTIC, (hence the "P") The PLASTIC takes the form of various types of resin (could be polyester, epoxy, vinylester, or other type of resin).

 

[FF]

The PLASTIC takes the form of various types of resin (could be polyester, epoxy, vinylester, or other type of resin).

True but the plastic created by any form of resin has almost no structural strength.

Any resin simply holds the glass in place , some like epoxy does a better job of holding to the surface its laid on , so makes the best repair.

 

[sbman]

I would sand that down until all the cracked, loose and broken fillers and gel coat are removed. I'd then lay a couple layers of 1708 with epoxy to stabilize it and additional layers to build up areas where 1/4" of filler was needed, peel ply that and let it cure.

Then after it cures, peel the ply and apply fairing compound, but don't make it 1/4" thick, that won't survive that's why I'd add glass to build up thickness as needed. Fair as much as you want to get a surface smooth, then paint with your favorite marine paint and/or grip additive.

For the section you pictured, that's a few hours of work spread over a few days. There's many ways to approach this repair and it looks to be cosmetic in nature.