Stupid newb hull repair questions.

jinxd12

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New to this forum but not to tinkering on projects! I have a couple questions that I can't seem to get a zeroed in answer on. I've searched on here for pictures and 100 videos on youtube. So I signed up so I can learn from the great help on here.

I aquired a 70s Chrysler Bowrider with a 75hp Chrysler outboard, decent shape but the front hull has some damage I need to address.

My questions are I know how to layer the fiberglass but can I use large pieces of MAT and stack like the videos show, the damage is about 18"x 20". The damage isn't a hole....almost like the outer skin is peeled off (deeper than the gel coat)

Can I fix this with epoxy instead of fiberglass...I have read multiple points of view, but I know epoxy is strong as hell.

Opinions, pointers, help is appreciated! Trying to upload pics but won't let me.
 

Woodonglass

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Either resin will work IMHO polyester resin is easier to work with and more than adequate for what you're describing grind and feather the damaged area then use a few layers of CSM I'm assuming you don't have acces to this area from the inside
 

jinxd12

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The floor is still in very good condition, I'm in Arizona so I don't want to rip it up. What is CSM?
 

Baylinerchuck

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Chopped strand mat. It's what you use with poly resin. Layering this creates a very strong repair.
 

jinxd12

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Thanks! Is there a brand that stands out from the rest that I should use for the poly resin.
 

tpenfield

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:welcome:

If you can post some pictures of the area needing repair that would help with advice. I sort of understand what you need to do, but a picture or two would help.
 

jinxd12

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No Title

Looks like someone tried to fix it once, I know I have to grind it all off.
 

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gm280

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Seeing the pictures explains things a lot better. It really looks like the gel coat has separated from the fiberglass. And you have to first peel off everything you can and then grind the edges to feather them out so you can do any type repair. I would also grind the fiberglass to remove and iffy areas to get to good fiberglass so the new repair would adhere to it. Not going to be easy to do being underneath. But it is what it is. I would also use 435 laminating polyester resins with CSM (Chopped Strand Mat). A lot of guys on these forums like to use US Composites for their fiberglassing materials. But that depends on your location. JMHO
 

Baylinerchuck

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It actually looks to me like someone spread some Bondo short strand filler all over the bottom of the boat. That will definitely need to be ground down so you can see what your dealing with. As far as brands go, most folks get supplies from US Composites. There are others, perhaps even someone local to you. Just be sure you are using products intended for marine repairs and layups. Stay away from the products sold at home improvement stores or automotive parts retailers.
 

jinxd12

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Hey guys finally got to attack the bottom of the boat. Seems to be about 1/2-3/4" of Bondo on this sucker. I couldn't get the very bottom of the hull, trailer was in the way. I'll figure that out later. Is what I have so far look like I'm on the right track, maybe an easy fix? Opinions are always welcome!
 

gm280

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Hey guys finally got to attack the bottom of the boat. Seems to be about 1/2-3/4" of Bondo on this sucker. I couldn't get the very bottom of the hull, trailer was in the way. I'll figure that out later. Is what I have so far look like I'm on the right track, maybe an easy fix? Opinions are always welcome!

You can jack up the bow to allow you access to that area and then and everything off until you get to solid material again. Then post a picture or three for us to see what you have. If there are no serious hull issues, you could go back with fresh gel coat and finish it off hand sanding. But that remains to see at this point.

If you do decide to jack up the bow, use some 2 x 6 or even wider wood to spread the jacking load over a larger area. That way you won't be applying all the jack force in one small area. JMHO
 

jinxd12

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I'm not real sure how i would jack up the bow, I believe I have what they call a tri-hull/Chrysler cathedral. Plus I have the motor still mounted on the boat, trying to finish up the grinding this afternoon, if I can figure out how to jack it up will make it 100x easier!
 

jinxd12

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Ok guys, got the boat up enough to work on it, and went to town with the grinder. So some bad news is the Bondo concoction was hiding a decent size crack/hole about a foot long.

Crazy thing about this model boat is what I have researched is there isn't any stringers, just filled with foam. After poking around in the keep that I exposed there is just foam in there. Same look as the cockpit where I have begun to rip the floor out. I'll attach some pics please let me know what you think, and help on how to fix it.

I already have some Evercoat polyester resin THIX formula, and 5 yards of 1.5 ounce CSM, hopefully this is what's needed.
 

gm280

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Ok guys, got the boat up enough to work on it, and went to town with the grinder. So some bad news is the Bondo concoction was hiding a decent size crack/hole about a foot long.

Crazy thing about this model boat is what I have researched is there isn't any stringers, just filled with foam. After poking around in the keep that I exposed there is just foam in there. Same look as the cockpit where I have begun to rip the floor out. I'll attach some pics please let me know what you think, and help on how to fix it.

I already have some Evercoat polyester resin THIX formula, and 5 yards of 1.5 ounce CSM, hopefully this is what's needed.

First let me say this. You hole in the hull is fixable. I have a tri-hull boat I'm working on (for too long) and it too had a large hole in the hull much like yours. However, I repaired it and I now can't even see where that hole was. So don't worry about that.

Secondly, I used 435 laminating polyester resins with 1708 and CSM. It depends on what you are dealing with when you are making repairs what the better fiberglass material you could use.

While I never used Evercoat Polyester Resins THIX, it seem to be used for fiberglass hull repairs,so it will work for your application. I think you will more then 1.5oz Chopped Strand Matt material though. I would look for 1708 material. It is designed to give both a women material AND a CSM sewn together to make a stronger repair.

We need some pictures to see what you are dealing with. SO post them and we can offer the better way to attack your repair. But it can be repaired to work and look like new again. JMHO
 

jinxd12

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Hey gm280 I did post pics, i think I posted 5. Just have to click the link, the files wouldnt post on here so I had to use a link from my google account. The pics are very good quality to help everyone see.
 

gm280

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Okay I did look at them now. I would say you need to attack this repair fro both sides. And that does mean you will have to get to the top side of the hole to get it prepared and fixed. The end results will be great. But it will take some repair from the top as well as the bottom to make it solid again. But not to worry, we are here to help and assist with ideas, suggestions and techniques.

I suggest you read over some boat repair threads on here to get a idea and feel for what you have to do . You have to grind out any suspect material and feather it in preparation for the repair material. It is going to take a few applications to build up the thickness, but really not hard to do. JMHO
 

jinxd12

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Ok I think I feathered the bottom of the boat enough tonight. Pics attached. Also ripped up the floor and started removing the foam, what a Pain in the ass. I'll finish the removal tomorrow. Let me know what you think of my removal of junk around the keel.
 

jinxd12

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I got the top of the hole exposed, what do you think now? I've seen multiple ways to fix from the top, best I've seen is put tape loosely on the bottom and lay a few layers of mat on the top. Then once it's dry, sand the outside down and repeat the process from the bottom, sand and paint.

If I'm wrong please explain to me! Pics attached in the links.
 

gm280

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jinxd12, you can't go wrong following chevymaher's suggested video. The guy on that video knows his fiberglass. I will say you did a pretty nice job on the top side feathering the fiberglass. But you need to feather out a lot farther as well. Because you are trying to make the new fiberglass repair structural attached to as much older material as you can to make it sound. And you also need to feather the bottom in the exact same manner. Then follow the patch via the video. You will come out with a solid sound repair that if you do it correctly will be hard to tell when you repaired the hull after finishing. JMHO
 
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