How's Your Bottom Doing These Days ?

[Ralph Johnstone]

I recently became involved in a discussion here about bottom paint and was called out for stating that I was getting six to seven years out of an application of bottom paint. "Impossible" he said. I knew it was a hell of a lot better than my previous applications of Micron CSC but didn't think it was earth shattering. It's ablative and as long as it's thick enough, the party just keeps going, and going, and going.

I'm curious to hear:
- what other people use
- what their results are
- years between re-coating
- where is their location
- what their water is like
- whether they periodically scrub in the water
- and any other pertinent information.

In my own case:

Type of paint: West Marine CPP Ablative Antifouling Paint

Results: after an application of two coats, went six years without seeing the black warning coat. Every half haul had a light coating of slime. I did one (1) bottom painting with CPP in 2013 and the second painting in 2019 . The boat sees a good number of miles each season.

Location: coast of British Columbia

Maintenance: no scrubbing in the water during sailing season, or ever for that matter.

Surrounding water: bloody cold.

IMHO, applying TWO coats of CPP is what makes it last longer. I will also say that when I did paint in 2019, I did not see the warning coat but had come prepared for painting so did it anyway (I know I could have waited until 2020). Also CPP is less than one half the price of Micron CSC. CPP also appears to be slightly harder than CSC when the boat is in the slings. Doesn't stain the slings so heavily. I never bother to sand or scrub as the power washing gets the surface spottless. Mind you, still have to brush scrub under the slings .

Thanks for any info you can supply .

 

[Charles Erwin]

Ralph

Is your permanent moorage influenced by any fresh water source? Does your boat go to dry storage in winter?

 

[sail sfbay]

Ralph Johnstone...........six to seven years out of an application of bottom paint is remarkable and extraordinary!! I will have consult with fstbttms, who has a boat bottom cleaning business in the San Francisco Bay.

- what other people use - 2 coats Pettit Trinidad Pro SR hard paint (recommended by my hull cleaning diver)
- what their results are - 3 years painting interval
- where is their location - San Francisco Bay
- what their water is like - saltwater 52-54 degrees F with high concentrations of dissolved silica, phosphate, nitrate plus nitrite and ammonium (likely from agricultural run-off) based on published data
- whether they periodically scrub in the water - bottom cleaned every 3 months by my hull cleaning diver
- and any other pertinent information - receive a bottom paint condition report every 3 months from my hull cleaning diver AND avoid a berth where the keel is in the water at low tide (unfortunately cannot avoid that in my berth at low-low)

 

[dLj]

You say coast of BC - are you in fresh or sea water?

 

[dLj]

Ralph Johnstone...........six to seven years out of an application of bottom paint is remarkable and extraordinary!! I will have consult with fstbttms, who has a boat bottom cleaning business in the San Francisco Bay.

@sail sfbay you must have missed to original post, it was @fstbttms that called out @Ralph Johnstone on the
number of years stating no bottom paint maintains its anti fouling that long, irrespective of how well the bottom actually appears.

dj

 

[fstbttms]

Ralph Johnstone...........six to seven years out of an application of bottom paint is remarkable and extraordinary!! I will have consult with fstbttms, who has a boat bottom cleaning business in the San Francisco Bay.

As I mentioned in a another thread (the precursor to this one), Ralph's claim of 7 years of anti fouling performance is not realistic, whether he is aware of it or not.

- what their water is like - saltwater 52-54 degrees F

The water in your marina is easily 10 degrees warmer than that right now.

...with high concentrations of dissolved silica, phosphate, nitrate plus nitrite and ammonium likely from agricultural run-off

While I have no actual data to back this up, while high concentrations of these nutrients may be found up in the Delta, I suspect that the in the central Bay (where your boat is located), tidal flushing keeps this kind of pollution to a minimum.

 

[Davidasailor26]

What I use: Pettit Vivid (a hybrid ablative).

Results: No hard growth (don’t think there would be any where I am anyway). Slime and some soft growth starts in mid summer but is manageable.

Years between re-coating: One coat per year, with light-moderate 80 grit sanding before application. Usually burnish with wet 400 grit before launching. In high use years the high wear areas show the warning coat by late fall.

Where: Upper Chesapeake

What the water is like: Basically fresh. Lots of nutrients for soft growth from Susquehanna runoff. No hard growth on underwater structures. Temperatures climb into the low 80s by summer.

Periodic scrubbing: Zero to 2 times per year. If I’m motivated I scrub once around early August and maybe again in late August. Some soft growth comes off, mainly in the upper couple feet where the light reaches.

 

[Tally Ho]

I am on Lake Michigan, south of Chicago.

Fresh water, fairly clean, and warm (80 F in summer), and hard (frozen) in winter.
Boat spends about April -October in the water. ..7 months. Other 5 she sits on the hard, outside.

I use VC-17 hard anti-fouling paint.
I apply a fresh coat every other year, and do touch up on rudder, keel, waterline, on the off years.

I get the boat out at least 1 or 2 times a week (so she is not a dock queen).

I get some light slime and over the summer. No hard growth.

I don’t usually clean the bottom during the season.

Boat is hauled at end of October and the hull is pressure washed before it is put on stands.

Greg

 

[thinwater]

Micron CSC is very common on the Chesapeake Bay, as a two year paint (several coats). Three years, maybe, if you put on more extra coats and you're really not fussy (meaning you will have some growth). But not a day longer. There is nothing magical about CSC. It's just a good paint.

 

[Ralph Johnstone]

Is your permanent moorage influenced by any fresh water source? Does your boat go to dry storage in winter?

Thanks. We have a small creek which flows into our marina basin. Almost dries up in the summer. Our tides average about 10 ft/day as seen below so very little dilution and no dry storage at any time:

what their water is like - saltwater 52-54 degrees F with high concentrations of dissolved silica, phosphate, nitrate plus nitrite and ammonium (likely from agricultural run-off) based on published data

Got to wonder if that soup promotes algae growth on your hull.

You say coast of BC - are you in fresh or sea water?

We're in the big Pacific.

As I mentioned in a another thread (the precursor to this one), Ralph's claim of 7 years of anti fouling performance is not realistic, whether he is aware of it or not.

Just to juice things up a little , I found a picture of a half haul out from 2018. I had previously applied two coats of West Marine CPP in 2013. The bottom paint was now five years old. What's interesting is that our marina was hammered that winter by barnacle growth (first time in 18 years) everywhere it could grab on:

We could hardly get the boat to move. Great clouds of black smoke everywhere. Once the boat was moving, we couldn't get it to stop. We moved the approx. 500 yards to the lift with three people and three boat hooks. This was the first trip of the year. We knew before we started moving we had drag problems BIG TIME. We went in for a half lift:

Notice that the prop and shaft were heavily coated with tight barnacles but the hull only had the usual light coating of slime which pressure washed off easily. Just like the zincs. Ablative action right before your very eyes.

I left for five minutes to see a man about a horse and when I came back, the prop and shaft were covered with smoking foam. One of the yard guys had poured his magic elixir over the barnacles and everything was now spotless after it was rinsed. He used HYDROCHLORIC ACID and it looked damned strong. I almost had a seizure on the spot. One of the guys I was with replaced the zincs while I continuously ran a hose over the gleaming metal until they got the boat back in the water STAT. My biggest concern was the acid that got into the cutlass bearing. Ran the boat flat out in Howe Sound for an hour. Cutlass still tight three years later.

@fstbttms , this is not just a claim, it's right in front of your eyes with photographic evidence, like it or don't.
My claim of 7 years of anti fouling performance is not realistic, ? ? ? ? ? What more do you want for proof ? Come up with something realistic and I'll provide it. How about a video of the boat coming out of the water with that days newspaper displayed ? I'm not about to spend a fortune getting half haul outs just to look good. What, and then turn around and get a full haul out and bottom paint later and not disclose it. Oh brother !

 

[Ralph Johnstone]

Where are all the sailors in the Pacific Northwest ............................. ? Obviously out sailing.

@Stu Jackson , @Hello Below , @YVRguy , @Phil Herring , @jssailem , @leo310 , @Terry Cox , @MikeHoncho , @FastOlson , @Tedd , @Michael Davis , @Tricia , @John Nantz , @ComoxSweetCaroline , @RickSegal , @VisionPNW , @Irek , @DinghySailor , @Ken Cross , @Mark Maulden , @LeslieTroyer , @Bob&Cherie&CM and every other sailor in the PNW.

I would be eternally in your debt if you would be so kind as to supply any information you have regarding your bottom paint:

I'm curious to hear:
- what is the brand name of your bottom paint
- what are your results
- years between re-coating
- where is your location
- what is your water like
- whether you periodically scrub in the water
- and any other pertinent information and remarks you could share.

Thanks very much for your help.

 

[fstbttms]

@fstbttms , this is not just a claim, it's right in front of your eyes with photographic evidence, like it or don't.
My claim of 7 years of anti fouling performance is not realistic, ? ? ? ? ? What more do you want for proof ?

As I said before, your fouling is so light that you could probably get away without bottom paint. Even West Marine and the manufacturer of your low-copper, low-priced CPP ablative paint product, Pettit Paints, recommend 2-3 new coats of this stuff PER SEASON. And why is it that every single other person who has commented on your paint longevity claims in two different threads has remarked how unusual a 7-year paint lifespan is? Not one other person has said, "Oh yeah, I routinely get six or seven years from a bottom job." Because it doesn't happen, that's why. Everybody else who uses the same paint that you do has to renew it every year or three. Why? Because the copper biocide in it has leached out to the point where it will no longer adequately retard fouling. Your paint is no different. The difference is that in your location, there is little or no fouling to be retarded.

 

[Terry Cox]

Since we purchased our boat in 2002, in need of a bottom job, I gave the boat two coats ablative in 2004. The again in 2011, and the last one in 2018. We cruise year around, so the ablative does a good job sloughing what marine growth appears between cruises. By year seven it is due, but in prior years, the first two are clear of any mussels or barnacles. Then they slowly start to appear, but I hire a diver each year to clean all the bright work and install new zincs.

Sometimes a month will go by before we head out, but by the time we return most all the marine growth is gone only to reappear by the next time out. I've been using West Marine brand black ablative for years and am pleased with the performance in keeping our bottom pretty clean.

 

[sloughsailer]

My boat lives in Suisun Bay near Port Chicago in a small minimum maintenance marina. The water temperature is warm and almost fresh during times of heavy flow in the Sacramento and San Joaquin Rivers. But it becomes salt in the summer when flows decrease.

Barnacles aren't a much of a problem. But the plant growth is incredible. After a couple of weeks tied up the boat leaves a trail of weeds when leaving the birth. I used to run her aground on the east end of middle ground and go over the side with my brush and scrub the hull and keel clean. This is hard to do now since the Navy got security conscience and hired boat cops to chase boats away.

I used to use high copper hard vinyl and now am using West Marine ablative (CCP) with which I'm not impressed. The boat has been in the water since early spring and I'm going to haul it soon and try another paint.

 

[fstbttms]

I used to run her aground on the east end of middle ground and go over the side with my brush and scrub the hull and keel clean. This is hard to do now since the Navy got security conscience and hired boat cops to chase boats away.

You clearly need regular in-water hull cleaning. Why not hire a diver to do it at your marina?

 

[Ralph Johnstone]

Well, it looks like the vote(s) is/are in from the Pacific Northwest and we have 100% agreement that ablative paints up in the PNW can last into the 5 year+ service life.

@fstbttms , you know how much I hate to disagree with you, but I came upon a Boat US article which IMHO may throw a little more light on this subject :

How Long Does Boat Bottom Paint Last?

Here's a look at bottom paint for boats, its application, and how to find the type of boat bottom paint that's right for you.

www.boatus.com

This is pretty much what I'm seeing up here. I gauge my time to paint when I can see that black warning coat. I never see anything but slime on the light blue hull (right up to the end) which removes easily enough.

Last time when I painted after six years, I still couldn't see any trace of black but seeing as how I came loaded for painting, I decided to paint. What I don't know is how long could that have gone on ? ? ? ? ? As I start preparing for the next bottom painting in 2025, I will hold off until the year I positively do see the black warning coat.

I wonder what motivates others when to re-paint their ablative. Maybe Boat US doesn't have a clue about ablative paint. Or maybe people are painting their ablatives far more often than they need to. It's a tradition kind of thing, you know ?

 

[fstbttms]

Following that logic, you could paint your boat once with an ablative, let it sit in its slip for 20 years and then take it out sailing knowing that you had what was essentially new paint on the bottom. Following that logic, the only way biocide is released from an ablative paint is by water moving past the hull. I'm sorry, but that simply isn't true. If it were, boats painted with ablatives would grow more foul than their hard-paint brethren when not being used or cleaned. And that is not the case.

Ablative paints absolutely passively leach biocide while sitting in their slips or on their moorings and anybody who says otherwise doesn't know what they are talking about including the author of the article you posted.

So here's some proof of what I'm talking about: On the left is the passive leach rate category your paint (West Marine CPP) falls into. On the right is the leach rate category a high copper hard paint (Pettit Trinidad) falls into. While the hard paint certainly leaches more on a daily basis than your ablative, the ablative is also certainly leaching copper while it is just sitting there, thereby negating the claim made in the article above.

 

[fstbttms]

Let me ask you this- If (after 7 years) all you are getting is light slime on the hull, why bother to repaint at all?

 

[Michael Davis]

I think it depends on where you moor your boat and sail it. Our previous boat was kept on the Fraser River and sailed In salt water. We went ten years without painting the bottom. Fraser River silt kept it sanded smooth as silk. ( not sure the paint was doing any good at all). With this boat we keep it in salt water and haul out every couple of years whether it needs it or not ( Micron CSC). Had a diver on it this morning, a few barnacles and muscles on the prop and the bottom of the keel , zincs were still good, but it’s only been about 17 months since our last haul.

 

[JamesG161]

I am chiming in after the Leach Rate data presented above.

Leaching is a transfer of one material [Cu ion] to the surrounding waters.

The Rate of Transfer is dependent on...
1) Temperature of the water
2) Exposed painted surface area of the hull.
3) Velocity of water passing the hull.
4) Concentration of Cu ion in the paint, but absent from the Waters.

Thus very variable, depending on each boat and sailing experience.

In my case...
1) One coat of Petite Trinidad SLR color Red
2) Top Coat of Petite Trinidad SLR color Navy Blue
Note: that happened by accident in Jan 2014.

But like @Ralph Johnstone , when the Blue wears away, we see the intact Red coat under it.

A Diver cleaned our boat in March 2020 [ note to @fstbttms , Passed that diver's info to you for your Divers link site]

Diver remarked: "Nothing to clean on your boat bottom", but noted the Red exposure on the Blue Rudder from Prop Wash.

In talking with Petite directly and describing my current "on the Hard" Boat, they said one coat of
Petite Trinidad Pro [Navy Blue] over the previous coats.

After reading this thread and a previous one...

Everybody is probably correct

Jim...