Has anybody used this bottom paint?

[Just a Tinch]

Living in SW FL... I have always used Pettit Trinidad hard paint for the bottom, and had good results. But I am looking at trying Sea Hawk's hard bottom paint. I was wondering if any of you all had ever used it and what kind of results you had.

Thanks!!

[GordMay]

Why are you “looking at trying Sea Hawk's hard bottom paint” (”Tropikote”), when you've always had good results with "Trinidad" ?

Is it price?
Or do you wish to switch to an epoxy-based antifouling (like Pettit “Unipoxy")?

[Just a Tinch]

There are a couple of reasons... First, I can buy it for about $40.00 a gallon less than Trinidad...and they have a slightly higher cuprous oxide level.... plus they are Florida based company, and have done a lot of advertising that their product is excellent.

I'm not one to fall for advertising...so I would rather get endorsements of products from people who have actually used them.

At this point its pretty much a curiosity thing....so I'm fishing for advice.

I've used Trinidad for years...but their price has skyrocketed over the past couple of years, and like most people I like to get the most for my money.

[GordMay]

I was vaguely aware that the cost of bottom paint had risen over the past several years, but didn’t realize the full extent until I looked up a 2004 price for Trinidad ($150/Gal), and compared it to a current price of $300/Gal.
In the late 90's Trinidad was available for well under $100/Gal.

FWIW:
To calculate the amount of Bottom Paint required per coat, divide the Wetted Surface Area by the square foot coverage per gallon, of the particular product you are using.

A close approximation of wetted surface area can be calculated:
Wetted Surface Area = LOA x BEAM x 0.85

Hence:
Paint Required (Gal.) Per Coat = (LOA x BEAM x 0.85) ÷ Coverage (Sq. Ft./Gal.)

Assuming 2 Coats, and a coverage of 320 - 400 Square Ft. Per Gallon, a 37' LOA x 12.5' Beam boat would require about;
[(37 x 12.5 x 0.85) ÷ 350] x 2 ≈2.25 Gallons (1.125 Gal/Coat)

[Just a Tinch]

Thanks for the formula....mine was a little more of a guesstimation or WAG if you will. Our boat is 44' X 14.5'.... so I was anticipating needing 5 gallons, but your formula gives me a requirement of 3.38 gallons...or rounding up: 4. I'll probably go with 5 gallons since the boat has twin rudders and is a full keeled displacement hull... so the wetted surface is a little greater. I hate buying the paint...and running out before I am satisfied with the job.

At West Marine... Pettit Trinidad starts at $215 for the standard, and the SR is $243. Some significant "increases" in cost... some of which I attribute to WM having acquired BoatUS...and lacking any local "competition"....they have raised prices beyond any normal inflationary market impetuses. So I have sought out other sources and am pleased to have found a couple.

[little boat]

i used the petit trinidad black for many years, but the last two applications convinced me that they must have changed the 'recipe' as its antifouling properties were a big disappointment.
i decided to quit with the hard paints and avoid the buildup and sanding involved and switched to a seahawk ablative.
i've been very happy with the seahawk i used, (also black), but i believe i am using a type with high tin only available outside the U.S.

[Pblais]

I'll be doing 2 coats of Sea Hawk Ablative in the next few days. It's a Florida based paint company. My price is $180 / gallon. By the numbers it compares to the amount of copper in the better paints from the various better known vendors. The hard paint is rated 18 - 24 months but I doubt anyone south of Maine can get 24 months so if you need 2 years I wouldn't choose the hard paint. It is a good paint from all the reports we have had abound here. Many of the Waterman are going with the hard paint to gain a knot. They put on a lot of miles over the year. While not as tough as Tampa, FL, our summer water gets pretty warm here.

[Microship]

Little Boat - interesting thought about the possible change in formulation of Trinidad. A Seattle boatyard put it on my trimaran just a little over a year ago, and when I sold the boat in August, it flaked off easily during the haulout. I don't know if the paint (which had a good reputation) has changed, or if the yard just did a lousy prep job (sure paid enough...).

Cheers,
Steve

[fstbttms]

Originally Posted by Microship

I don't know if the paint (which had a good reputation) has changed, or if the yard just did a lousy prep job (sure paid enough...)

Sounds like a preparation issue. Trinidad is as good now as it has ever been, IMHO. Also, for those bitching about the price, bear in mind these two tidbits:
1.- The price of most metals has skyrocketed over the last year or so. Copper included. This drives the price of anti fouling paints up.
2.- More cuprous oxide does not necessarily mean better anti fouling performance.

[GordMay]

Originally Posted by fstbttms

... 2.- More cuprous oxide does not necessarily mean better anti fouling performance.

The majority of antifouling paints are copper-based, in which the main biocide is cuprous oxide (Cu2O) (or cuprous thyocianate).

Although Copper content (typically 20 to 76% copper content) isn’t the only factor in a bottom paint's effectiveness, I’ve always thought that a higher Cu content paint, applied to a greater total film thickness, would last longer.

Perhaps someone (fstbttms ?) could explain the biochemistry:
- how biocide leaching rates determine a paint’s antifouling efficacy
- and the mechanisms by which the biocide is delivered.

[Just a Tinch]

Thanks for your replies.

Typically down here, I have always applied 3 coats to the hull, and two more at the water line. This has netted me 3 years before having to repaint the hull. Growth here is a significant problem....as we are in "brackish" water.

Now some of you may rear up over this....but one other trick that I have tried and learned that works...is to add "animal grade tetracycline" to the paint, and it does increase the efficacy of the paint. When our sailboat was hauled out for the survey...after 3 years, there was ZERO growth on the hull. I have been rather pleased with the results of this mix.

[GordMay]

Tetracycline in antifouling paints
CAT.INIST
A recent yachting magazine article advocated the use of capsules of the antibiotic tetracycline to be added to cheap copper-based paints. The impact of such a paint on non-target bacteria, algae and oysters was investigated. Tetracycline was found to leach rapidly from painted surfaces and degrade quickly in seawater.
The concentrations released were insufficient to cause any deleterious effects on marine organisms, including those responsible for fouling boat hulls

[Pblais]

Now some of you may rear up over this....but one other trick that I have tried and learned that works...is to add "animal grade tetracycline" to the paint, and it does increase the efficacy of the paint. When our sailboat was hauled out for the survey...after 3 years, there was ZERO growth on the hull. I have been rather pleased with the results of this mix.

We have a few folks around here that get three years. I saw a trawler last week that did. Mostly it's from all the extra coats they puit on. Sounds like your extra coats help a lot too.

[Vasco]

Over the years I have tried most of the "top" bottom paints. When I got my Beneteau 4 years ago I specified Trinidad SR. Don't know if the yard did a poor job or what but it didn't last two years. Had to scrub every two weeks in the Bahamas. I decided to return to an ablative as I'd used Micron CSC in the past. I tried Ameron which makes a high copper content ablative mostly for commercial use. Didn't impress me. This year I'm going with Supershipbottom, an ablative that sounds interesting. The boat is on the hard all summer so I think an ablative will fare better than a modified epoxy hard coating. I know Trinidad seems to be the most popular paint but I haven't had good luck with it.
Super Shipbottom* Hard Ablative Antifouling Paint

[fstbttms]

Originally Posted by GordMay

Perhaps someone (fstbttms ?) could explain the biochemistry:
- how biocide leaching rates determine a paint’s antifouling efficacy
- and the mechanisms by which the biocide is delivered.

I just spent 20 minutes typing up a little dissertation how anti fouling piants work, pushed the wrong button and lost it all! Auuuugh! Now I don't have time to re-do it but will later today.