How much bottom paint is too much?

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David

Ok, Here's a different type of bottom question for your thoughts. Recently, I had a bottom job done on my sailboat. Due to some mix ups, the yard accidently put the wrong paint on the bottom. (Let me go on record as saying that it was an honest mistake and the yard has made good--no complaints) Anyway, as it stands, the boat will have 2 coats of Ultra-Kote with two coats of Interlux Ultra with Biocide on top of that for a total of 4 coats. It was originally supposed to get only the Ultra with Biocide. Anyway, The yard which is very reputable has agreed to take care of the mistake and apply two more coats of the Ultra. With that said, I ask you, is this overkill or the bottom job of the century (and maybe the lucky deal of the century). Shouild I expect the bottom to last longer or is that just wishful thinking? I'd love to hear your thoughts.
 
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SH

Shutup now, and use a different surname...

Hello... You are the winner, let live and let live, but use a different surname when you go back for pin-striping or they will find a way to short you... It will last longer per se' but will inevitably flake off a bit, but the grungies won't like the next fresh layer... Not to mention the 'sealing' attributes of Ultra... If they scraped it off (usually with old planer blades welded to long handles), there is the inevitable trouble of the the 'cheap kid' gouging (sp) your gel and not saying he did so resulting in blisters next season, so you are definately best off with the recoats if they roughed up the base or painted over a tacky base... Again, you win, unless you are an anal racer concerned with half pounds of weight that are not represented in deep bulb ballast... HINT - use a sealed chemical peal when time comes to remove the flaky gunk, don't allow them to do it mechanically... SH.
 
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Bob Howie

Deal of the Year

Both are good paints and since the usual bottom covering is 2 coats, then 4 coats is twice as good, wouldn't you think? Actually, it is and you're so much the better for it. Pop a top on a coldy and rejoice.
 
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David

thanks

Thanks for the responses. I thought I came out pretty good considering. Hopefully, this might get me past the magical 2 year bottom ritual.
 
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Bayard Gross

Is Ultra Coat an ablative?

Unless I am mistaken, I do not think Ultra Coat is an ablative style anti-fouling paint. It is, I beleive, a modified epoxy that produces a harder bottom than an ablative. My concern here is that you will have an awful lot of paint to sand off next time you put on anti-fouling paint. So, maybe better to suffer with some slime to make matters easier for next season. I think you should check the label on a can of Ultra Coat to see if it is an ablative. Do this yourself, don't take someone's word for it.
 
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Joe

They're both modified epoxies, Bayard.

I don't think David or his boat yard are that stupid. The Ultra-Kote is supposed to work well over good existing paint. I think he got a cool deal from a concientious boat yard.
 
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David

More on the environment the boat is in

It was recommended that perhaps this would be overkill and it might be better to accept a little slime growth. Here's why I'm so interested in losing the slime. The area the boat is in is extremely prone to soft growth. As an example, I had a quick haul/powerwash done recently. In 2 weeks, the bottom had regrown it's skirt to the point that I lost over 2.5 knots under power. IN TWO WEEKS!. I would call that severe growth. I figure that with the ultra as the top two coats, slime should have a tough time and with 2 coats of ultra-kote under that, hard stuff shouldn't have a chance. Both of these paints are hard type. With 4 total coats, could I expect longer bottom life (ie-top coat wears off--there are still 3 coats left) or does the effectiveness of the underlying coats diminish over time? In other words, as the top layers wear off, do the under layers act as a "fresh" coat when they be become exposed. I hope that makes sense.
 
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Joe

The answer is No, I think...

... the reason I say, I think, is because I read the description of Ultra-Kote in the west marine catalogue and it indicated that the paint would work well over existing, good, bottom paint. What that means, I don't know. If it means that the paint has some type of ablative feature to let it erode away as it becomes ineffective, or it doesn't stifle the older layer's properties, then I would think your premise is valid. However, if it is like other modified epoxies, in that it dries to a very hard shell and only the paint's anti-fouling properties erode away, then my feeling is the subsurface paint's anti-fouling properties may be "trapped" beneath the shell of the final coats. When cleaning my own boat I have noticed the bottom paint swirling off, especially if I use something abrasive like a brush or a scouring pad. My feeling is that after a year or so a more aggressive cleaning technique might assist in removing the older paint, and exposing the good paint underneath. A final comment: why don't you call the Interlux people, not the yard, and get their opinion on your application, then post their reply. This is a very interesting subject that I'd like to understand better.
 
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Jim LeBlanc

Bottom paint coats

I had a similar experience on my last bottom job. The yard was supposed to use two coats of black paint and they did it in blue the first time arouund. Like your yard, they appologized, left the blue on and then applied two coats of black. This has worked our very well. It has been nearly three years since the bottom was done. The black paint is all gone now but the blue layers are still working and I intend to do the bottom again this winter.
 
Apr 19, 1999
1,670
Pearson Wanderer Titusville, Florida
Should be OK, but...

Ultra and Ultra-Kote are both modified epoxy paints. The copper biocide is embedded in a matrix of epoxy. As the biocide dissolves, it leaves pores in the matrix through which the water enters to dissolve the fresh biocide farther in. As a result, the effectiveness of the paint diminishes gradually with time and you should expect to scrub off some new growth every so often (more on this later). Finally, when the biocide is all gone, you'll have the distinct pleasure of sanding off four coats of old epoxy matrix. Now for the good news. Conventional wisdom says ablative paints like Micron CSC are better than modified epoxies because, as they wear, fresh biocide is being continually expose, The paint surface retains full effectiveness over time, and when it's all gone, just slap on some new paint and go. However, for ablative paint to wear, the boat must be moving. If it sits at the dock most of the time, the surface will gradually lose its effectiveness and you'll grow a seafood salad just like with the modified epoxy paint. So, you'll have to scrub just like everybody else and while you're doing that, you're also scrubbing off expensive ablative paint into the water. When you scrub a modified epoxy, none of the biocide is lost. The moral of the story: You pays your money and you takes your chances. Four coats are better than two, but probably not twice as good. See link below to Interlux website for more info. Happy sailing. Peter H23 "Raven"
 
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David

Feeback from Interlux

Someone asked if I had contacted Interlux. Well, I did that and I must say, not too impressed. I described the situation and was told that there were no compatability issues. I then asked what type of "life" I could expect out of the paint. I explained that the boat was slipped year round and sailed regularly in warm salt water. I said that 2 years seemed to be the normal life in my area. I was told by the Interlux rep "you'll never get 2 years out of the paint, regardless of # of coats. Besides, after 6 months, the Biolux will have bleached out of the paint so you won't have amy soft growth protection and probably only marginal hard growth protection". What the????? I found this hard to believe especially since they push the Biolux as the next coming. Plus, the rep was rude. Next time, I'll think hard about another paint manufacturer. What do you guys think? I'll be very curious to see the boat in 6 months.
 
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Joe

David, thanks for the feedback on Interlux....

...it confirms that some expensive paints are over-rated. My understanding is that the antifouling properties in modified epoxies have a limited life span, no matter how many coats you apply. As to your negative experience with interlux, consider that they probably don't deal with the consumer as much as they do distsributors and other middlemen. They would never claim the biocide would last any longer than the minimum just to avoid litigation. Keep us posted on your bottom paint condition, please.
 
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Jack Swords

Try contacting another rep

Sorry about your rude contact. I have had 2 coats of Interlux Ultra-Kote on my boat for 5 years. It has been in La Paz warm water in the slip and sailed regularly only 6 months of the year. The bottom is cleaned once a month by a diver (hence a hard paint). He has never complained of needing new paint, but I will do it again in November with the same paint as I need to haul. The previous paint was redone after 4 years in CA, just in prep for life in Mexico. Had problem with Interlux rep when asking about compatability with Tin (still available in Mex.) He just said I couldn't use tin (a law, but still being used). Never got an answer. Still, I'm quite satisfied with the long life of the paint.
 
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David

Time will tell

I know my experience with the Interlux rep was probably the tail end of a bad call or bad day, but I was suprised at the answers I got. For now, I'm going with the word of the owners around me. Everyone seems to get at least 2 years, so I will quick haul every so often and see whats going on. I'll try to keep you posted if anyone has any interest in hearing further, or if the issue has been beat to death, I can just slowly slip away under the waves......
 
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David

First sail with new bottom

Ok guys, I just became a believer in Interlux. My boat is a C30 Tall Rig. Today I sailed her for the first time with the new bottom paint. The wind was very steady around 15 with gusts to 18ish. 1-2ft seas with light chop. AVERAGE SPEED--6.9 knots!!!! Much of the day was spend at 7+ and peaked at 8.5 knots. I can't explain this as the max theoretical hull speed on the boat is 6.7 knots. To the best of my knowledge the knot log is accurate. Can a brand new bottom make that much difference?
 
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Bayard Gross

You bet!

Especially with a modified epoxy which is a "hard" paint as opposed to ablatives that are relatively "soft" paints. And that bottom should be smooth as well, not roughed up as it will be in a couple of years. Nevertheless, unless you want the additional volume of more coats of paint, you will have a jovial time removing all that modifed epoxy.
 
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