the saga of the hull crack continues. thundercraft tri-hull.

Thought I would start a new thread here, got my digital camera charged, and took some pics.

Here's the front view of the boat, you can see where I have sanded and prepared the gelcoat area where the crack is...


Here's some close up images of the affected area.






And one with my hand in view to show size of area.


The fiberglass sheet or mat you see underneath there is rough woven and seems devoid of any resin. It's just dry. Is this normal?

So, here's my thinking. I just bought this boat, and would really love to be able to enjoy it this summer, so I bought a fiberglass repair kit from bondo. My "plan" is to go out there tonight, and fill that area I sanded in with a mixed resin, and tomorrow after it has hardened to go out and sand it smooth again, and put two additional layers on the outside with resin and cloth, covering about 3 inches from the outside of the cracked gelcoat area.. then sanding it smooth again and painting over the patch.

While it wont be really pretty, should this solution work for me until I can take everything apart and fix it this winter?

Am I nuts for thinking this would work?

Thanks for all of the help, I have been looking in many threads on here, and would never have had the guts to sand this hole in the gelcoat (since this started as a small crack) without seeing how many of you guys have tackled your issues by yourselves.

Re: the saga of the hull crack continues. thundercraft tri-hull.



Oops, here's the other side..

Thanks for the help!

Re: the saga of the hull crack continues. thundercraft tri-hull.

You might have to grind off a bit more of the gelcoat. You really want that patch fiberglass to fiberglass. It will work fine for the summer. So the woven fiberglass is dry? Then you are golden. If you can get at it from the other side that would be perfect but as long as it holds and does not leak.

Re: the saga of the hull crack continues. thundercraft tri-hull.


Here's a photo of the patch after applied last night.

I ran out of time after smoothing the first layer on, and had to wait an hour before applying the second with new batch of resin. It feels pretty strong today! I hope it gets me through this summer, and next winter, I can separate the top and bottom half of the boat, and go at it from the inside and do the gelcoat repair on the bottom. I will most likely sand and smooth the edges of the patch, but think i will leave it unpainted for now to make sure it is holding up.

Thanks for the advice. By the way, what about the mat or cloth being dry or devoid of resin under the gelcoat makes that a good thing?

-Pete

Re: the saga of the hull crack continues. thundercraft tri-hull.

First off, is that repair done with epoxy or poly resin? If epoxy it may last, but I doubt it if it is poly. You have the patch mostly adhered to the gel coat and it doesn't look like you feathered the area back much. I would have feathered the area back a lot mor and only put a patch on that was about the size of the exposed glass after feathering. I also see it is a cloth patch and it doesn't look like you have any mat under it. If it is poly, cloth only, and adhered to the gel coat, I would bet it can be pulled off pretty easily.

Yacht Dr. has a nice photobucket album showing a repar:

http://s699.photobucket.com/albums/vv352/YachtDr/Sun509/

This one has a hole and he used a "filler" first, but you get the idea of how it should be done.

Re: the saga of the hull crack continues. thundercraft tri-hull.

Well, I suppose if this fails I will just turn this into a "What not to do in case of your gelcoat cracking" thread. LOL.

Re: the saga of the hull crack continues. thundercraft tri-hull.

Bob_VT said:

If you can get at it from the other side that would be perfect but as long as it holds and does not leak.

Click to expand...

My thoughts exactly.

The Bondo kit uses poly resin just like most every boat is made with. Repairing a spot like yours with that is fine. With proper prep it would likely last for years. You really want to grind out all the bad and feather it back some. If you can do it from the back side you'll have less "finish" work to do on the outside.

Re: the saga of the hull crack continues. thundercraft tri-hull.

Its not faired anywhere near enough, there should be no step, looks like you did it by hand, thats tough to do. I would extend that out at least 6 inches, no gelcoat all around for 6 inches, so the area should be ground out about 14 inches wide.

The idea is to give the resin a greater glue area and reduce the depth of the repair to something more shallow, shallow means less heat, less shrinkage in the curing resin, less likelyhood of it coming loose.

The dry glass needs to be ground out from inside, then replaced with an inside patch. Thats why the exterior is failing.

Re: the saga of the hull crack continues. thundercraft tri-hull.

I started sanding by hand, and after about 2 hours in the heat, decided to go and get a little edge sander. It took another hour or so to do what I did. That gelcoat is some tough stuff! I am thinking the previous owner hit the dock or something at that level to cause the cracked gelcoat. I am going to take her back out tomorrow for a little ride and see how this patch is going to hold up. Luckily, it's above water level in anything but the most choppy water.

I am just looking for something temporary until I can separate the hull and get to it from the inside. I think from that point, I might have to enlist the help of someone who has done this kind of work before... at least to begin with. Having just bought her, I would hate to have to take the hull apart to repair it, and likely have to wait until next season to enjoy the water.

Looks like I bought, and got, a 1500 dollar boat

Re: the saga of the hull crack continues. thundercraft tri-hull.

Took her out today. The patch worked great!!!






Unfortunately, that's not where the water was coming in. I had to run the bilge a LOT. So, on a whim, I let it go as long as I felt comfortable, and then pulled her out of the water to see where water was coming out. Right before the transom on the bottom, the wood on the trailer had rotted, it looks like the previous owner had it jump up and down on the metal brace there, and it punched a nice 1" little hole right there.

So, tomorrow it looks like I will be pulling the boat off of the trailer and replacing those and putting another patch down there.

Re: the saga of the hull crack continues. thundercraft tri-hull.

I imagine your flotation may be water logged too If you are hauling around water soaked foam you are killing the performance too.

Re: the saga of the hull crack continues. thundercraft tri-hull.

Wow, I haven't really thought about that much. Performance seems pretty good. She planes out very quick, and tops out at 37mph. I'd hate to see it better

Tomorrow should be an interesting day. I am going to try to get it all finished with some help from a friend of mine, and back in the water by the 4th. Just got back from Home Despot.. bought the new 2x4's for the trailer, but they didnt have any stainless steel hex bolts for attaching them to the braces. Would galvanized be okay?

With a little luck, lots of cursing and some elbow grease, I think it is doable.

Re: the saga of the hull crack continues. thundercraft tri-hull.

Took the boat off of the trailer today, have it on 3 jackstands. Looks spooky as all get out.

Fixed the trailer. Sanded the hole, filled it with resin, and covered it with 4 layers of cloth and resin. I will post pics later, just too tired to do it now. LOL

I havent put it back on the trailer yet, I am waiting for the patch to cure.

I decided against putting carpet back on the wood on the trailer... if the wood hadnt been carpeted in the first place, I would have seen the damage as it happened. (if it happened during my first outings, that is)

Re: the saga of the hull crack continues. thundercraft tri-hull.

maybe u could only carpet the parts of the wood where the traler brakets r not , so there would b no carpet only on the traler braketed area of the wood just an idea had to say something i dont want the bare wood to grab or rubb ur new boat and create unesasery friction...

Re: the saga of the hull crack continues. thundercraft tri-hull.

Yr old thread, did the patch hold up we wonder?

Re: the saga of the hull crack continues. thundercraft tri-hull.

Capt-pete has not posted since Sept 2009, so I doubt he will see this thread and post the results.

There is the possibility that the reason he hasn't posted is because the patch didn't hold up and he is no longer among the living.

Re: the saga of the hull crack continues. thundercraft tri-hull.

This is a good "what not to do thread" I am a newbie at restoring my boat but even as I was reading this I was saying to myself "what"? No removal of the gelcoat, no filler, cloth only to glass up the hole, no carpet of the 2x4's, then cloth again on a 1 inch hole under the water line????

Mark42- you may be right