More bottom paint questions!!!!

[Slim pickins]

I didn't want to hijack another thread so I started this one.
I have a 79 Catalina 25. I sail in freshwater only. The boat will be on a trailer except for weekends and maybe one week out of the summer. The bottom on the boat now has been stripped from what I can tell. I have no idea what was on it before(no previous owner). My plan was to just barrier coat it with interprotect 2000 and be done with it. Will the barrier coat get chalky after a year or should I put a topcoat of something over the barrier coat. I know I don't need antifouling but what else would you paint over the barrier coat?

 

[kloudie1]

Harley, give the folks at Interlux a shout.. they will answer this one.. I think the barrier coat should be protected with a layer of something, but I don't know what that is.. Since you don't need anti fouling paint, a polyurethane paint would probably (?) be fine after wet sanding the barrier stuff.

 

[DannyS]

You might want to look into VC-17. That's what we use up in the Great Lakes.

 

[Steve Dion]

Why bother with a barrier coat? The purpose of the barrier coat is to "help" prevent blisters. You are not going to get blisters over a weekend or over a week.

 

[Roy10289]

I agree with Steve. You are not in the water long enough to have bottom growth or blister problems. Spend your money on other improvements or creature comforts... enjoy

 

[Slim pickins]

i understand that i really dont need a barrier coat, just like i dont need an antifouling, but the bottom has been stripped/sanded almost all the way down to the fiberglass weave in some spots. The bottom definatly needs a barrier coat, to reseal it, but also to make it look acceptable. I've also removed some thru-hulls and patched the holes, so im also looking at the barrier coat to cover all the cosmetic blemishes.

 

[kenn]

i understand that i really dont need a barrier coat, just like i dont need an antifouling, but the bottom has been stripped/sanded almost all the way down to the fiberglass weave in some spots. The bottom definatly needs a barrier coat, to reseal it, but also to make it look acceptable. I've also removed some thru-hulls and patched the holes, so im also looking at the barrier coat to cover all the cosmetic blemishes.

We also sail off the trailer.The previous owner used to leave the boat in all season, so there was some ancient anti-fouling; last year I stripped the bottom all the way to gelcoat.

While experimenting with strippers, I inadvertently stripped some gelcoat right down to the underlying fg. I repaired this, and other gelcoat dings and scratches, using one of the Evercoat gelcoat repair products.

For this year I'm either just maintaining the gelcoat, or I might put an epoxy finish on the bottom, like the Soling and Melges racing boats at our yacht club.

 

[dscribner]

Harleyworker,

I'm in the same boat (forgive the pun) and have been looking at single stage paints. There are several that boast being perfect for us trailer sailors. They're hard, non ablative and glossy. You might search a little deeper for one of those. I think SM1000 was one of them. But I just don't recall. Post what you find out anf photos of your project. I'd be interested in how things go.

 

[Joe]

If it was me, I'd protect the new barrier coat with a couple coats of a medium priced ablative paint. A gallon will be more than enough for the job and is very simple to apply. Maintenance coats once a year will be all you need after that.

 

[jcastle]

The easiest and most effective, and most economical is a barrier coat system and an self-polishing bottom paint as mentioned above. I have used the Tuff Stuff epoxy system by Sea Hawk and their AF-33 bottom paint. For less than $250 bucks you can get the product you need that will last for several years. After that just put another coat of bottom paint on it every few year to make it new a fresh. These products are designed to last under the water line. I would be careful with a polyurethane as you might have adhesion issues down the road.

 

[CharlieCobra]

My old V-21 sailed off a trailer for 35 years without barrier coat or bottom paint with no issues, even in saltwater.

 

[jcastle]

Yea, but if you are down to raw fiberglass.....you need to barrier coat!

 

[Slim pickins]

I will definatly be barrier coating, not only to protect the fiberglass from osmosis, but to also give me a decent cosmectic surface. I'm basically wondering if the barrier coat will get chalky like all epoxys. If so then what paint can I put over it to keep the bottom smooth and shiny that is not an antifouling/ablative.

 

[CharlieCobra]

VC-17

 

[Steve Dion]

Read this!

http://madmariner.com/blogs/alan_hugenot/640

 

[caguy]

This is a very timely thread. I just finished sanding the old ablative paint to a smooth finish. The PO lived on the boat, I only plan on keeping it on the water for 3-4 weeks at a time. I don't like the ablative paint in that it is very messy when working around the boat on the trailer.
Am I correct in using a hard antifouling paint?
Will it stick to the ablative paint?
Should I primer first?
Should I go with an ablative paint again?
What should I use for the boot stripe? It had a vinyl stripe before. WM recommended a one part polyurethane paint. They don't stock two part paint.

 

[Joe]

This is a very timely thread. I just finished sanding the old ablative paint to a smooth finish. The PO lived on the boat, I only plan on keeping it on the water for 3-4 weeks at a time. I don't like the ablative paint in that it is very messy when working around the boat on the trailer.
Am I correct in using a hard antifouling paint?
Will it stick to the ablative paint?
Should I primer first?
Should I go with an ablative paint again?
What should I use for the boot stripe? It had a vinyl stripe before. WM recommended a one part polyurethane paint. They don't stock two part paint.

No.... do not use hard shell paint (modified epoxy) if you store you're boat out of the water.... read this WM advisor... I've included an excerpt:

http://www.westmarine.com/webapp/wc...11151&catalogId=10001&page=Anti-fouling-Paint

Antifouling Paint Choices
Copolymer/Ablative Paints


Copolymer paints release biocide at a constant controlled rate throughout their lives, wearing away or "ablating" much like a bar of soap. Paint wears off faster in higher drag areas on the hull and appendages. These paints work well in high-growth areas and continue to be effective after haul-out and relaunch. Copolymer paints, such as West Marine PCA Gold, Interlux MicronCSC and Micron Extra, offer true multi-season protection, lasting as long as there is a reasonable coating thickness. Because they expose new biocide until the coating is worn completely away, additional coats add to their longevity. We recommend a covering of two or three coats on the first application. Copolymer paints with anti-slime additives are best for heavy fouling areas.
Ablative paints (of the non-polymer type) work in a similar way and minimize the annual ritual of sanding when applying a fresh coat.
Best use: Boats that are used often, but are not serviced by a diver. Not recommended when you want a super-smooth bottom finish and have a diver maintain it, since scrubbing removes paint and reduces longevity. Must be repainted if the boat is pulled out of the water for winter storage. All ablatives of both varieties share the advantages that they can be applied over most other types of antifouling paints and do not create a paint buildup.
Hard "Contact Leaching" Paints

If you keep your boat in the water year round you are most likely a candidate for a modified epoxy paint that prevents growth by leaching biocides upon contact with water. Contact leaching paint releases the biocide at a steadily decreasing rate, leaving the hard coating of the original thickness at season's end. Higher copper content, rather than the type of paint binder as with ablative paints, generally means greater effective performance in this paint type. Modified epoxy paints adhere tenaciously to most surfaces, and can be applied over most types of paints. On the down side, they lose effectiveness when the boat is stored out of water.
Best use: Range of products from inexpensive single season coverage (like West Marine Bottomshield and Interlux Fiberglass Bottomkote) up to top quality multi-season protection in high-fouling environments (such as Pettit Trinidad or Interlux Ultra). Ideal for sailboats and fast powerboats, due to its ability to resist abrasion and be burnished to a smooth surface. Avoid when you don't want paint to build up from annual paint jobs.
Dual Biocides

Paint suppliers add a second biocide to some versions of their coatings, using formulas such as Biolux, Irgarol and zinc pyrithione and zinc omidine. These additives block photosynthesis near the water's surface and restrict the growth of algae.
Thin Film Paints

Fresh water locations like the Great Lakes are plagued primarily by algae, and thin film paints such as VC 17M Extra and are a good choice for these environments. They offer a super slick Teflon® finish to keep growth from attaching to the hull in addition to one or more biocides.
Best use: Freshwater or cold, low-fouling salt water or high performance boats that benefit from the friction-reducing properties of Teflon.

 

[sailingdog]

You need to barrier coat, as you're down to bare laminate. Then you need to use a bottom paint that will work even with extended haul outs—this means a multi-season copolymer ablative paint.

I'd recommend going with a Petitt brand rather than an Interlux brand, as the speed required for the paint to ablate is lower for the Petitt brands generally.