What bottom paint for PNW...

[thinwater]

I find it surprising how many people keep coming forward to say that they are getting 4, 5, and six years from bottom paints while the purists keep whining "The label says to repaint every one to two years ."

Barnum knew what he was talking about.

Because it depends on where your boat lives. People struggle to get two years in many places. For example, in the PNW you have consistently cold water, which slows leaching. The water temperature at my dock is currently 79F (Chesapeake Bay) and rising. We get near-zero growth in the winter and very fast growth/leaching in the summer.

Bottom paint choices and performance are very local. I've done extensive paint testing, but would not presume to say what is best or how long it might last, somewhere I have not tested. That would make me the sort of fool Barnum was talking about.

Also, I repaint when it is due, not according to the label. But here, often they coincide.

 

[Ralph Johnstone]

Because it depends on where your boat lives.

@thinwater , I was far too thin on backfilling in any info in my comments about people getting extended life for botom paint. I thought (and was mistaken) that reference had been made earlier to people in the PNW getting up to eight years of ablative life on a single coating.

It is my unwavering belief that there exist in the marketplace, certain bottom paints which, when exposed to PNW waters, have exceptionally long life expectancies. In all likelihood limited to ablatives.

It's either that or too many people are going along with the crap that sales groups are concocting to slap on the sides of antifouling paints :

The West Marine CPP which is shown above is what I am now getting 7 years out of two coats applied in one session of painting as opposed to their advice of every season.

If you :

• do not have any barnacles adhering to the bottom of your painted hull.
• do not have any sign of the tracer coat showing through.
• and slime is easily removed by power washing.

................ then DO NOT TOUCH.
Wait for the next year's haulout and reapply this check list.

 

[Stu Jackson]

Ralph and thin are right. It is ALL about WHERE you are and what you use.

For decades in SF I used Trinidad Pro, hard paint. I'd go from three to six years between painting. Last one was in April 2015, left SF for BC in 2016. Diver did bottom monthly in SF.

First haul in BC was June 2020, 2 coats Epoxycop hard. Next paint was October 2025, no barnacles but was due, Micron ablative over hard, no hard paint available. No diver service in BC.

Seems cooler water does affect paint longevity (except for that one long time in SF, but I sailed weekly during that one longest time span).

 

[thinwater]

... If you :

• do not have any barnacles adhering to the bottom of your painted hull.
• do not have any sign of the tracer coat showing through.
• and slime is easily removed by power washing.

................ then DO NOT TOUCH.
Wait for the next year's haulout and reapply this check list.

Exactly.

I will add a modifier.

When a paint begins to fail in a warmer climate, being "good" at the end of a season, or even when the water first warms, does NOT mean the paint will not fail halfway through the season. The water is warmer here, there are more nutrients, and the season is longer. My paint (9-1-2023) was perfect in May and is now growing weed at a considerable rate. Occasional hard growth too. It will be bad by fall, and a particular sailor, racer, or one who does not want to clean, would rightfully call it failed at this point. But it was perfect just two months ago. The water was cold two months ago.

Every place is different.

 

[Hayden Watson]

@thinwater , I was far too thin on backfilling in any info in my comments about people getting extended life for botom paint. I thought (and was mistaken) that reference had been made earlier to people in the PNW getting up to eight years of ablative life on a single coating.

It is my unwavering belief that there exist in the marketplace, certain bottom paints which, when exposed to PNW waters, have exceptionally long life expectancies. In all likelihood limited to ablatives.

It's either that or too many people are going along with the crap that sales groups are concocting to slap on the sides of antifouling paints :

View attachment 238420

The West Marine CPP which is shown above is what I am now getting 7 years out of two coats applied in one session of painting as opposed to their advice of every season.

If you :

• do not have any barnacles adhering to the bottom of your painted hull.
• do not have any sign of the tracer coat showing through.
• and slime is easily removed by power washing.

................ then DO NOT TOUCH.
Wait for the next year's haulout and reapply this check list.

I think you may have been thinking of my post but I don't use an ablative. I use Trinidad Pro which is a hard modified epoxy and get 9 years in Oak Harbor, WA. I dive the boat spring and fall to clean the bottom and replace zincs. In that time, I get no hard growth on anything except for the uncoated prop and shaft and a few rough spots on the lead keel. This is a photo of Papillon fresh from the water. It had been 6 months since the last cleaning and 9 years from the last haulout.

 

[Ralph Johnstone]

My paint (9-1-2023) was perfect in May and is now growing weed at a considerable rate. Occasional hard growth too

Hard or ablative ?

Speaking of ablatives (at least I was), would you say that if ablative paint is still present, the hull is still safe ? I'm working on the idea that if the ablative had lost its biocide toxicity, it would have been previously washed away.

That's been my mantra for many years now and the only thing that will get me up off my lazy haunches to pick up a paint brush is the revelation of the tracer coat. So far so good .

 

[Ralph Johnstone]

I use Trinidad Pro which is a hard modified epoxy and get 9 years in Oak Harbor, WA.

We have a new winner in the longevity contest of bottom paints.

You gonna let 'im get away with this @Terry Cox ?

 

[Drinky Crow]

Speaking of ablatives (at least I was), would you say that if ablative paint is still present, the hull is still safe ? I'm working on the idea that if the ablative had lost its biocide toxicity, it would have been previously washed away.

Dunno'. Two years in the Petit Horizon sluffs off in big clouds when worked w/a foam blade.
The divers still treat it as toxic.

Ultrakote 76% co.
Trinidad Pro 65% co.
Trinidad 57% co.

Those are hard paints that stay on the hull until removed.
Are they any worse for environment than...

Odyssey 44% co.
CSC.ca 42.7% co.
Horizon 42% co.

...which are ablative and end up in the water?

Since I berth were sea-velcro flourishes and the bottom needs frequent race day scrubs I guess this haul out I'll be applying Interlux Bottomkote-ca (42.79% co) to keep the divers happy .

 

[Hayden Watson]

Dunno'. Two years in the Petit Horizon sluffs off in big clouds when worked w/a foam blade.
The divers still treat it as toxic.

Ultrakote 76% co.
Trinidad Pro 65% co.
Trinidad 57% co.

Those are hard paints that stay on the hull until removed.
Are they any worse for environment than...

Odyssey 44% co.
CSC.ca 42.7% co.
Horizon 42% co.

...which are ablative and end up in the water?

Since I berth were sea-velcro flourishes and the bottom needs frequent race day scrubs I guess this haul out I'll be applying Interlux Bottomkote-ca (42.79% co) to keep the divers happy .

The sluffing of ablatives is why I like my hard paint. I dive my own boat and I get very little of the blue cloud when I wipe off the slime. I use a cheep white scrubber pad and it comes off with a single wipe. It lasts about 10-years.