Advice on “minor” fiberglass repair

[not_yoda]

I am contemplating putting an offer in on an ‘88 Catalina 34... however, there are some areas of the fiberglass that need to be repaired.

As far as I can tell, these are just minor repairs... I can’t identify any soft-spots or any other signs of water ingress.

Assuming these are just superficial, any tips on how these should be repaired and how “difficult” it might be?

appreciate the assistance!

[Sailmonkey]

That’s not fiberglass repair, it’s gelcoat repair. Cosmetic for the most part, color match will be impossible, inexpensive to do though.

[406Columbia]

That looks VERY minor to me, but I am sure more seasoned folks will chime in. If that were mine I wouldn't even do much to fix it other than some thickened epoxy and fair it, then touch up the paint. One appeared to have some slight cracking, if it bothers you you could take a dremmel and grind out the crack. Then prime it with standard epoxy and after a few minutes pack it with thickened epoxy then fair and paint.



Over the last year or more I have filled hundreds of cracks, holes and glassed more than I care to ever again in my life. West Systems has a great amount of resources and great tech support. Check this out https://www.westsystem.com/instruction-manuals/


Anyway glass is super easy to work with in most cases and if you take your time and follow instructions it seems hard to go wrong. No need to pay anyone else to do it for you, especially small repairs like those.

[nightowle]

I second 406 Columbia's statement. You may need a bit of filler but it's mostly gelcoat. There are several brands on Amazon in small tubes you can get. Color matching is the difficult part. It will look better, and maybe not too noticeable, but never 100% perfect.

[ArmyDaveNY]

If you do not currently have any marine epoxy on hand, or are not familiar with epoxy for repairs, it is not very difficult, as the others have said. The areas that need attention look small, so you may want to check out the West Systems 105K and 101T repair kits. One of the nice things about the kits is the convenience since they eliminate the need to collect stuff, and eliminate the need to measure amounts.

The 105-K is great if you don't have anything on hand. It provides everything you need including gloves. The epoxy comes in eight or ten small packets allowing for an easy set up for each repair.

The 101-T is similar but without the accessories such as the gloves. I have done the repairs with and without using gloves, so they are not necessary but the do make clean up easier.

Good luck with your repairs.

[jhulmer]

Those are caused by air bubbles in the gelcoat and are an easy repair.

1. clean out with wax remover, alcohol, or acetone. (must be clean). you could very carefully clean the void out with a Dremel tool.
2. place a piece of clear boxing tap under the repair spot, pealed back so you can roll it up and over the spot when filled with gelcoat.
3. you can buy small gelcoat repair kits at West Marine that have a color match pigment with the white gelcoat. Matching is difficult so I suggest just use the white. The gelcoat in this kit is thickened slightly and has a wax cure agent. If you have white gelcoat you will have to add a thickening agent like cabosil or micro balloons and maybe wax.
4. fill the void with the gelcoat using the tube spot or a syringe and roll the clear tape over the repair. Try and judge the amount to just fill the void. Use a squeegee or drivers license to roll the tape up. If you use your fingers you can displace the gel out of the void.
5. let cure over night and pill the tape off. The finish may be good enough for you or you can wet sand with 400 and 600 grit and buff with a cotton wheel in the dremel and a little compound to blend in the repair.

note: use only polyester gelcoat, epoxy degrades in UV. Also Gelcoat will NOT stick long term to epoxy.


Jim

[not_yoda]

great advice here... thanks for that!

i have put the offer in... let's see what happens next

[ArmyDaveNY]

Jim, in post six, brings up a good point that I forgot to mention. Epoxy is not UV resistant so in order to get a long lasting repair, you much remove the amine blush from the epoxy. It is easy to do and if done properly, you can paint it and the repair will last a very long time. Washing and sanding (once the epoxy is fully cured) will sufficiently prepare the epoxy for painting/gelcoating. This link provides some good advice. N.B. the link talks about major epoxy repairs so your actual work will be much less. Page sixteen talks about prepping for paint.
https://www.westsystem.com/wp-conten...-Finishing.pdf

I just took a quick look at the photos and the one photo looks like the fiberglass is exposed. The others may just be gelcoat issues and there may be no need to epoxy those.

[not_yoda]

Originally Posted by ArmyDaveNY

Jim, in post six, brings up a good point that I forgot to mention. Epoxy is not UV resistant so in order to get a long lasting repair, you much remove the amine blush from the epoxy. It is easy to do and if done properly, you can paint it and the repair will last a very long time. Washing and sanding (once the epoxy is fully cured) will sufficiently prepare the epoxy for painting/gelcoating. This link provides some good advice. N.B. the link talks about major epoxy repairs so your actual work will be much less. Page sixteen talks about prepping for paint.
https://www.westsystem.com/wp-conten...-Finishing.pdf

I just took a quick look at the photos and the one photo looks like the fiberglass is exposed. The others may just be gelcoat issues and there may be no need to epoxy those.

on several of these i can see the individual GRP strands... for these, is it ideal to epoxy fill first, and then gelcoat? or is it just enough to just gelcoat?

this video makes sense to me

https://www.youtube.com/watch?v=r98AJs7BYIQ

[jhulmer]

Originally Posted by not_yoda

on several of these i can see the individual GRP strands... for these, is it ideal to epoxy fill first, and then gelcoat? or is it just enough to just gelcoat?

this video makes sense to me

As stated above it is not a good idea to put polyester gelcoat over epoxy the amine will leach out over time and the gelcoat will release.


These are not structural repairs all are cosmetic. Just clean the pits of loose fibers, grease, wax and use thickened gelcoat.

[stormalong]

Originally Posted by not_yoda

on several of these i can see the individual GRP strands... for these, is it ideal to epoxy fill first, and then gelcoat? or is it just enough to just gelcoat?

this video makes sense to me

Don't use epoxy. Use polyester filler if needed. For most of your pictures it looks like thickened gel coat is all you need. Polyester gel coat does not stick well to epoxy.

One tip on gelcoat: timing - once the new gel coat is hard but not fully hardened in the time to wet sand it. That way you won't take away a lot of the old gel coat while bringing down the patch. That is about one hour after catalyzing it. A day later it will be as hard as the original.

And see if Catalina can tell you the original gelcoat manufacturer or sell you some. The color will never match when fresh but can fade in to more closely match over time.

[Cadence]

Originally Posted by not_yoda

I am contemplating putting an offer in on an ‘88 Catalina 34... however, there are some areas of the fiberglass that need to be repaired.

As far as I can tell, these are just minor repairs... I can’t identify any soft-spots or any other signs of water ingress.

Assuming these are just superficial, any tips on how these should be repaired and how “difficult” it might be?

appreciate the assistance!

This might sound like a quip, it's not. For those little spots go to a cosmetic counter and match the lacquer nail polish with your gelcoat.

[skipmac]

Originally Posted by jhulmer

Those are caused by air bubbles in the gelcoat and are an easy repair.

1. clean out with wax remover, alcohol, or acetone. (must be clean). you could very carefully clean the void out with a Dremel tool.
2. place a piece of clear boxing tap under the repair spot, pealed back so you can roll it up and over the spot when filled with gelcoat.
3. you can buy small gelcoat repair kits at West Marine that have a color match pigment with the white gelcoat. Matching is difficult so I suggest just use the white. The gelcoat in this kit is thickened slightly and has a wax cure agent. If you have white gelcoat you will have to add a thickening agent like cabosil or micro balloons and maybe wax.
4. fill the void with the gelcoat using the tube spot or a syringe and roll the clear tape over the repair. Try and judge the amount to just fill the void. Use a squeegee or drivers license to roll the tape up. If you use your fingers you can displace the gel out of the void.
5. let cure over night and pill the tape off. The finish may be good enough for you or you can wet sand with 400 and 600 grit and buff with a cotton wheel in the dremel and a little compound to blend in the repair.

note: use only polyester gelcoat, epoxy degrades in UV. Also Gelcoat will NOT stick long term to epoxy.


Jim

Had to do a few spots on boat that were much like yours and this is exactly how I did it. A couple of them the color wasn't perfect but the repair was invisible from 4-5' away. A couple of the spots I got right on and you have to look close to tell there was any repair at all.

I used a gelcoat repair kit I bought from Defender. It came with a couple of small containers of gelcoat and initiator and several tubes of color. Also included some hints and instructions on mixing to match the color. The main thing I found, if you're trying to match an off white or very light color you only need to add TINY little drops of the color. For example to match a redish beige gelcoat I used maybe a pin point (note point, not pin head) of black, a very small drop of red and a pin head of yellow. This was for a couple of tablespoons of mix.

[skipmac]

I will have to dig up the old box to confirm but I believe this is what I used.

https://www.defender.com/product3.js...59992&id=16037

[cruising_ollie]

It might not be so minor. One of the pictures shows bare fiberglass not soaked with polyester. This is a sign of poor workmanship that might affect other areas of hull and deck. An expert should check this out.