Bottom stripping, voids on and in laminate Alberg 37

[Oldsailor27]

Hey guys,

I am stripping bottom paint down to fiberglass and finding lots of tiny voids in some areas. Today started to grind off some glass around the thrue hull and found some tiny voids inside the laminate. The laminate seem to be solid and quite thick and very dry, 7-8% moisture reading> This is my first boat 1975 Alberg 37 just bought mid June. Should I just sand it off, fill and fair and barrier coat it or should lay couple of coats of cloth over the whole bottom?

[boatpoker]

Minor imperfections, Nothing to worry about. Barrier coat and be done with it.

PS. Moisture meters cannot state percentage of moisture in fiberglass.
Moisture Meter Mythology

[Oldsailor27]

Thank you Boatpoker Do i need to completely strip the gelcoat to fiberglass or would it be ok to leave some and barrier coat over it?

[boatpoker]

Originally Posted by Oldsailor27

Thank you Boatpoker Do i need to completely strip the gelcoat to fiberglass or would it be ok to leave some and barrier coat over it?

Gelcoat is simply pigmented resin. No need to strip the gelcoat if it is sound.

[Oldsailor27]

Thank you, much appreciated.

[Stewie12]

Great advice !!!

[sailcrazy]

FWIW....based on advice we were given by a f/g expert/contractor, the gelcoat will wear out with time, will not continue to be impervious to moisture, and you will need to replace it at some point. But if you do not have a bottom blister problem, with multiple blisters popping up when you haul out, then you are likely not at that point yet. Ours failed, we had multiple small blisters every time we hauled and the hull dried some, and ended up having the hull peeled, faired, and a gelcoat reapplied. If you don't need that work done now, then from our experience I'd suggest there is no need to peel the hull yet.

[Clivevon]

The word everyone is not using is osmosis. Unfortunately I have learned more about that than I would like to know. However, your boat does not look to me like it has a problem of the kind you need to deal with now. The hull is 45 years old - if it hasnt developed a serious problem by now then I would think it probably never will. I am inclined to agree with Boatpoker - barrier coat it & be done - go sailing.
Be reassured your boat hull looks nothing like mine did before it had to be fixed. Its worth keeping an eye on it & I would recommend hauling the boat every winter as a precaution to let the hull dry rather than continuing to soak up water. If it gets large blisters & the distinctive vinegary smell of osmotic fluids then think again. You can look at https://www.interlux.com/en/ca/suppo...ognize-osmosis if you like, but honestly it doesnt look to me like a serious issue you need to be concerned about. Do apply a barrier coat though.

[s/v Jedi]

I recommend you do some work on it but nothing too difficult.

I would fill these voids, just doing spot repairs with a 2-part epoxy filler. I can recommend the TotalFair for this: https://www.jamestowndistributors.co...t-detail/97775

After sanding that nice and flat, 5 coats of gray Interlux 2000. Be sure to put the first coat of antifouling on before the last coat of Interlux cures (fingerprint test). If you are too late, instead of letting cure and sand, it’s better to add another coat of Interprotect and get the timing to antifouling paint right.

I did this job a couple years ago in the tropics and only got a 20-30 minute window so keep an eye on. If you are too late with antifouling, it will fall off and this is the most regular complaint. I got it right with a 4 people crew and it’s held up for 5 years already.

[Cheechako]

Minor. Roll on real epoxy before bottom paint for insurance as long as you are going that far on your prep. DONT peel it. . I'll be in the minority with that epoxy opinion, but that's ok.

[boatpoker]

Originally Posted by s/v Jedi

I recommend you do some work on it but nothing too difficult.

I would fill these voids, just doing spot repairs with a 2-part epoxy filler. I can recommend the TotalFair for this: https://www.jamestowndistributors.co...t-detail/97775

After sanding that nice and flat, 5 coats of gray Interlux 2000. Be sure to put the first coat of antifouling on before the last coat of Interlux cures (fingerprint test). If you are too late, instead of letting cure and sand, it’s better to add another coat of Interprotect and get the timing to antifouling paint right.

I did this job a couple years ago in the tropics and only got a 20-30 minute window so keep an eye on. If you are too late with antifouling, it will fall off and this is the most regular complaint. I got it right with a 4 people crew and it’s held up for 5 years already.

These "voids" are almost pinhead size. The barrier coat will fill them.

[Nicholson58]

Originally Posted by Cheechako

Minor. Roll on real epoxy before bottom paint for insurance as long as you are going that far on your prep. DONT peel it. . I'll be in the minority with that epoxy opinion, but that's ok.

You and Jedi are correct.

I’d fill with epoxy if you want perfection, sand.

My favorite is Interprotect 2000E. We applied 5 coats on Roxy after a serious blister repair. No repeats now, 12 years. I agree your bottom appears not bad. No peel needed. See my photos on this site under Nicholson58

[flyingfin]

Fill and Fair with AwlGrip fairing compound, just needs to be a structural repair, not cosmetic. The fish do not care how smooth your bottom is

[Oldsailor27]

Thank you all for your great advice. You really reassured me that the problems I’m working with are minor, and that the boat is in good shape. I’m going to move forward with the restoration with all of your advice in mind. Truly helpful guys, I really appreciate all of your input!
Hopefully I get the chance to pick your brains a bit in the future as new issues unfold.