Fiberglass Hull repair

[fuzzeywiggler]

Re: Fiberglass Hull repair

If your goin the painting route i needed 2 quartes of primer which covers fairly well and 2 quartes of paint that is mixed with a high quality mineral spirits. I did go with High quality marine paint also.
I have a 14' Vhull which i think has less surface area than a tri-hull so you will prob need a gallon of each. Find a local boat repair shop and you will get hooked up nicely.

Fuzzey

 

[BANGAZX10R]

Re: Fiberglass Hull repair

You should be able to get by with 2 qts of each, primer & top coat. I have a 17.5 ft tri-hull and used only 1 qt of each at 2 coats each, thats bow to stern. Now to do the bottom with the other 2 qts...I did thin the top coat paint a little;I'm using interlux brightside thinned with 333 brushing liquid.

 

[newbie_owner]

Re: Fiberglass Hull repair

He said it was just bondo, so I assumed it was regular automotive bondo, but yes either way I am going to take it all out. I will look into the v roller for the trailer as well. Is this area really hard to fiberglass? Should I actually cut out the area, or just sand it all the way down sill the glass is very thin, so that I can keep the existing contour? guess it will be kind of hard to get a nice curve otherwise.

 

[fuzzeywiggler]

Re: Fiberglass Hull repair

I would try to leave as much on as possible in that are because making that curve would be difficult but not impossible. I had one hole that i did one the bow section of keel that I had to fully cut out and it need multiple layers to build up and reshape. Make sure to cut out all the damaged area thats key. Then worry about the contour (mby a little handeling prob...or in the bottom of the lake...)

Fuzzey

 

[newbie_owner]

Re: Fiberglass Hull repair

Ok, I have sanded all the bondo down as you can see in picture 1.

Then I cut out all the damaged fiberglass as you can see in picture 2 and 3.

Then I sanded the area about 3 inches and beveled the edges so that the inside edge is the thinest as you can see in picture 4.

Now, what should my next step be? I can not get to the other side of the hole. Should I mix up some epoxy and cover some mat and place it on the inside and let it dry so that I have a kind of backing to start with?

 

[erikgreen]

Re: Fiberglass Hull repair

That'd be one way to do it. What I've personally done in the past is pull a trick that I use on sheetrock: Slip some folded cardboard into the hole and pull it flat with a piece of wire or string. Glue or glass it into place, then clip off the string flush and fair the hole.

Or, carve a piece of pink foam to fit the V of the hull and put it in the hole, then fill the edges with putty. When it hardens the foam should stick to the front of the hole and give you a surface to glass against.

For a hole the size you seem to have, the right way is to grind out the other side too, then glass cloth and mat to the inside before fairing the outside...

Erik

 

[i386]

Re: Fiberglass Hull repair

I had some pretty nasty holes in my hull, but I had the luxury of getting at them from both sides. More power to you. Your prep looks pretty good to me. I would make sure your taper/bevel extends all the way around the hole. It may be, but it doesn't appear so from the pic. Maybe it's just the camera angle.

Erikgreen's idea sounds good. You might also be able to put in some strips of packing tape starting at one side of the hole and working your way to the other side. You'll still have a small hole, but smaller than you have now.

Also, if you'll wet out your first layer or two of cloth/mat before you apply it, you might get it to do right without even worrying about the back at all.

 

[newbie_owner]

Re: Fiberglass Hull repair

Thanks,

I like the cardboard and wire idea, simple enough for me.

Ok, so how many layers of mat and coth should I use? and how should I layer it? Mat first? then cloth, then mat? My last layer, should it be cloth or mat?

 

[erikgreen]

Re: Fiberglass Hull repair

I'd probably measure the thickness of the hull near there and match it if possible.

If you're using polyester resin, then mat-roving-mat-roving-mat-cloth-gelcoat

or if epoxy, then roving-mat-roving-cloth-filler-paint.

Double up the layers of mat and roving as needed to match the original hull thickness.

Alternatively you could use as many layers of biaxial as needed to match the thickness, then fair and paint.

Erik

 

[newbie_owner]

Re: Fiberglass Hull repair

I will be using resin. After it is cured, do I and it then add fairing putty and smooth it out? Then prime? what kind of primer?

Can I use the boat if it is not painted? or should I just slap some paint on the patched area because I am planing to paint the whole hull later.

 

[Snatch]

Re: Fiberglass Hull repair

Im actually doing some glass repair on my boat right now. Im no expert by any means, but I would recommend after you let it sit and become hard sand it down with a 180 grit to smooth it out as much as possible !


Quick question to the people who have time in this kind of stuff I heard when doing glass work and you have a hole you gotta sand it 2-3 times the size that ways there more clean area to patch the hole ? just asking ? thanx

 

[newbie_owner]

Re: Fiberglass Hull repair

So is the first layer of mat the biggest (overlaps all the way to the paint), and each layer then smaller and smaller?

 

[ondarvr]

Re: Fiberglass Hull repair

Yes that will work fine.

 

[newbie_owner]

Re: Fiberglass Hull repair

Ok,

The hole is all patched up, looks messy but seems very solid ( I will post pictures later) So I am letting it sit for a few days, then I am going to sand it all down and ise the fairing putty to make it all pretty.


Once it is all sanded down and smooth, Can I use the boat? I what to make sure that I got all the holes before I re-paint eveything.

Thanks

 

[brian3127]

Re: Fiberglass Hull repair

i got a 75 tri hull with a hole that i already patched. in the same exact spot yours is and i had bondo in the patch too. thats wierd.

 

[newbie_owner]

Re: Fiberglass Hull repair

Ok,

The hole is fixed and without the use of BONDO.

I used a coulpe of layers of cloth and pushed it up into the hole and let it flatten out. I taped the hole from the outside until it was cured.

I then glassed by layering cloth, mat, cloth ect. I did about 6 layers.

Then I sanded it down and used the fairing putty.

Then sanded down the putty and primed it.

 

[newbie_owner]

Re: Fiberglass Hull repair

primed and ready to test it in the water

 

[jcsercsa]

Re: Fiberglass Hull repair

Man looks great !!! Good job !!!! let use know how the water test goes !! john

 

[newbie_owner]

Re: Fiberglass Hull repair

Well,

I took it out on the river for an hour, and it looked like the repair worked 100% I didn't take on a single drop of water.

I just got back from the cottage where I had it in the water for a whole week and still did not bring on any water. Took it tubing and in some choppy water, and everything looks great.

Thanks to everyone who helped me with this repair.

Next on the list:

Paint entire boat (top and bottom)
Redo deck
Redo carpet
Re-enforce dash
Redo seats
Change rollers on trailer to deep-V rollers