Why use bottom paint when you can scrape?

[Boatyarddog]

Originally Posted by Fore and Aft

Boatyarddog the big issue with not slipping regularly is if the growth gets to bad then you could damage the hull while removing the growth. I can clearly remember surveying one yacht that needed shovels to remove the reef on the bottom. A fair bit of gelcoat came away with the barnacles that time. Actually there's been plenty of times where heavy growth removal has taken a bit of paint and below the waterline ends up with a golf ball finish.
Maybe I am old fashioned but I like to be able to walk around our yacht on the hard every 18 months and just check everything is ok.
Personally when we go to use the yacht I like to step onboard and go. Not mucking around scraping the hull before we leave the marina. Not to mention we do a lot of Friday evening after work departures so there's no way I am swimming then.
Cheers

Fair enough, you'd have to admit that if they used shovels to remove growth, they were NOT maintaining it regularly.

Cause without paint that's what happens.
You scrape a bit more, depends on the local area.

In general it's useful to bottom paint.
I do not need the relief from scraping, I'm 65 but, this just isn't that hard.
So, paint away folks ,I'll just save the couple grand every 3 yrs.

And get a little exercise too.
I generally, scrape a bit at first, then move out of the marina, a mile or so, and finish off so as not to be in whatever's in the Local Marina waterway.
Takes 2, hrs.
Boatyarddog

[thinwater]

Originally Posted by Boatyarddog

...I disagree with the the thought that ablatives are less polluting than hard antifoulings. They are a source of constant release, as are hard coatings, but come off easier.
Are applied more often....

You can disagree, and your statement feels like common sense, but I believe if you read the studies and leach rates you will learn that you are incorrect about this. If both paints are multi-season, the leach rates are effectively they same and very little copper remains in either paint type at the end of 2-3 years... or they would not both be multi-season paints. Kinda obvious. Now, if you use a high-leach single season paint (CA has posted a list of leach rates, and there are other reports) and clean it excessively, it will leach more. But this is a case of not following the instructions.


If it were true, CA would have banned soft paints. But observe that they did not.


It's complicated, and I am encouraged to see that WA, for example, decided to step back and take a closer look. It seems that the EPA suggested leach rate may become the default guidance, and that is probably a good thing, because it will give the pain manufactures a target and give people like fstbottoms consistent rules. I hope.


--


Regarding damamge, I've taken a metal scraper to hard growth in some extreme cases. As long as the scraper is not sharp and the corners are rounded, it's not too dangerous, even to barrier coat IME. But as a regular practice, I think the result would eventually be different. Would you take a scraper to your topsides, with force, and not expect some gouges and wear over time? And some boats have pretty thin skins over the core.

[Boatyarddog]

Originally Posted by Fore and Aft

Boatyarddog the big issue with not slipping regularly is if the growth gets to bad then you could damage the hull while removing the growth. I can clearly remember surveying one yacht that needed shovels to remove the reef on the bottom. A fair bit of gelcoat came away with the barnacles that time. Actually there's been plenty of times where heavy growth removal has taken a bit of paint and below the waterline ends up with a golf ball finish.
Maybe I am old fashioned but I like to be able to walk around our yacht on the hard every 18 months and just check everything is ok.
Personally when we go to use the yacht I like to step onboard and go. Not mucking around scraping the hull before we leave the marina. Not to mention we do a lot of Friday evening after work departures so there's no way I am swimming then.
Cheers

I guess if your racing you'd want a very clean hull.

As a cruiser, I can scape as needed, and sailing the boat doesn't catch much debris.
As well, waves and fetch, natural scrapers there.
So sail it and be weed free a lot of the time.

Scraping also gives me the pleasure of "up close and personal" with the prop, zincs, thru hulls transducer, rudder.

Much more often than once in 3 years, at Zero Cost to me.

Makes sense, from a maintainance standpoint.
Boatyarddog

[fstbttms]

Originally Posted by Boatyarddog

What I meant is that to me it's seems completely plausible that soft ablatives would slough off more easily and therefore be more present in the water, than a hard ablative, all being ablative, as this has purpose.

No argument. But my point is that inexpert opinion (or even expert opinion, for that matter) is not science. And we shouldn't be making water quality policy based on opinion. If ablatives are so much more polluting, where are studies indicating that this is the case? There are none that I've seen. Yet in Washington it is illegal to clean these paints. Why? Because legislators were told that cleaning them caused a horrendous plume of color? That's not how smart policy is made.

[Josephcrawl]

Sorry to stir up such a **** storm. While we are getting controversial is it ok to put mayonnaise on a hotdog?

[Cliffhanger]

My boat had a thick build-up of antifoul when I bought it and I then added to that by my annual haul-outs. I plan to sand back to gel-coat next time we haul out. Of course, this means I keep putting off the haul out because it will be a huge, horrible job. So, for the last 2 years I have just dived regularly and given the hulls a bit of a scrape. This approach seems to have worked OK so far. I think I just keep exposing a new layer of anti-foul every time and of course, it means less sanding when I eventually do have the boat out.

[bensolomon]

I thought this study a few years back was well done. Covers much of what is being discussed:

https://www.practical-sailor.com/boa...tom-paint-2017

[Josephcrawl]

Originally Posted by bensolomon

I thought this study a few years back was well done. Covers much of what is being discussed:

https://www.practical-sailor.com/boa...tom-paint-2017

To bad they didn't cover ultrasonic. I'm curious what people's experiences have been with that.

[seandepagnier]

Originally Posted by Uncle Bob

Mate, you really don't get sarcasm do you.

In a text based forum without voice attenuation it can be impossible to detect.

Originally Posted by thinwater

Not in the MD Chesapeake Bay. The tide in only about 1-foot and the bottom is very soft mud. If you dry out most places, the waterline only falls 1-2 inches.

Where in the chesapeake bay? There is a combination of lunar and wind tides which varies based on the location. In the south there is sufficient lunar tidal range to careen. I would suggest just sailing to there.

If you can get up a river far enough the fresh water does wonders on fouling.

In the summer the jelly fish will be stinging, so that means full clothing, including a hood. Besides, if you don't wear a hood you get hordes of krill in your hair and ears.

I also know about this but deal with a few jellyfish stinging me. It hurts but the boat is clean. The stinging goes away after a few hours.

When the barnacles are in full swing, weekly scrubs are not enough. And you are working blind (I have scrubbed in the Bay). Doable, but not worth doing weekly.

I can get 80% of my bottom clean by reaching just my arm in the water from the kayak. I only have to get in the water to do the last little bit. In the past they used to scrape ship bottoms in various ways without getting in the water.

Originally Posted by GoodShipLolipop

Fun fact, something like 80% of the copper that has ever been mined by humans is still in use today. It just keeps getting recycled over and over again. From the bronze age to today, people just can't get enough copper.

I read somewhere that if the "transition to electric vehicles" is to go as "planned" which means no meaningful lifestyle changes and everyone can just use electric cars and boats, we will have to mine more copper in the next 20-30 years than in all of history up until this point. I am not sure how that is possible without emissions.

[thinwater]

Originally Posted by seandepagnier

... Where in the Chesapeake Bay? There is a combination of lunar and wind tides which varies based on the location. In the south there is sufficient lunar tidal range to careen. I would suggest just sailing to there. No Such Place. Sailed there for 40 years.

If you can get up a river far enough the fresh water does wonders on fouling. (That is more than 100 miles on these rivers. In most cases, it is not fresh until you go above the waterfalls, which is slightly impractical. There is a tide that far up, bringing enough salt to prevent die-off.)

I also know about this but deal with a few jellyfish stinging me. It hurts but the boat is clean. The stinging goes away after a few hours. OK. But it is part of the fun.


I can get 80% of my bottom clean by reaching just my arm in the water from the kayak. I only have to get in the water to do the last little bit. In the past they used to scrape ship bottoms in various ways without getting in the water. I kayak a lot, and getting in the water is easier. Also, the most important parts (keel, prop, rudder) are in-water jobs. The 80% figure... let's just say that is optimistic for most people.


The Davis Scrubis will actually do a lot more for soft growth than would seem obvious. I use it in the fall, when it's a bit to cold for swimming. But my prop, rudder, and centerboard swing up and don't need cleaning.


I read somewhere that if the "transition to electric vehicles" is to go as "planned" which means no meaningful lifestyle changes and everyone can just use electric cars and boats, we will have to mine more copper in the next 20-30 years than in all of history up until this point. I am not sure how that is possible without emissions.

See above

[fstbttms]

Originally Posted by Josephcrawl

To bad they didn't cover ultrasonic. I'm curious what people's experiences have been with that.

Two guesses as to why you don’t find ultrasonic systems in every West Marine in the country.

[Boatyarddog]

Originally Posted by fstbttms

No argument. But my point is that inexpert opinion (or even expert opinion, for that matter) is not science. And we shouldn't be making water quality policy based on opinion. If ablatives are so much more polluting, where are studies indicating that this is the case? There are none that I've seen. Yet in Washington it is illegal to clean these paints. Why? Because legislators were told that cleaning them caused a horrendous plume of color? That's not how smart policy is made.

Not at all strange or controversial, Washington State is mostly inland and subject to more stringent codes of conduct.
Legislation is based on studies done by Fisheries for years.
I suspect California, Even though a fore runner on Enviroment,is mostly open to the Ocean.
Washington is not, less flow = less chance for exchange of volume = more build up over time.
Departing from known causes of pollutants even if only a part of the problem must be addressed.
Because the problem requires multipoint solutions.
We are also a No Discharge Zone. And we all know it's NOT just boats.
Radical huh!
Boatyarddog

[seandepagnier]

Originally Posted by thinwater

No Such Place. Sailed there for 40 years.

In the lower bay I recall tidal range being at least a few ft. Depending on draft and also for scraping you can still be standing in 2ft of water.

not sure about chesapeake, but in new zealand I used to sail to fresh water


I really can reach 80% from my kayak.. It is easier to get in the water if its not really cold and there are no jellyfish. I dont have a wet suit right now.

my draft is 2ft. My outer hulls.. well one is always completely out of the water at anchor, so alternating which is dry by shifting weight avoids growth.

[Boatyarddog]

Originally Posted by Josephcrawl

Sorry to stir up such a **** storm. While we are getting controversial is it ok to put mayonnaise on a hotdog?

If you ask my Wife, Hell no!
I seriously don't know how anyone can dry scarf a hotdog down...
But, she can!
And take what you read here with a grain of salt, cause WE Are All experts here!
I support your choice to scrape and no paint.
We have opinions here that support it and those that don't.
Sailors
Boatyarddog

[Boatyarddog]

Originally Posted by thinwater

You can disagree, and your statement feels like common sense, but I believe if you read the studies and leach rates you will learn that you are incorrect about this. If both paints are multi-season, the leach rates are effectively they same and very little copper remains in either paint type at the end of 2-3 years... or they would not both be multi-season paints. Kinda obvious. Now, if you use a high-leach single season paint (CA has posted a list of leach rates, and there are other reports) and clean it excessively, it will leach more. But this is a case of not following the instructions.


If it were true, CA would have banned soft paints. But observe that they did not.


It's complicated, and I am encouraged to see that WA, for example, decided to https://cbf.typepad.com/bay_daily/20...he-likely.html become the default guidance, and that is probably a good thing, because it will give the pain manufactures a target and give people like fstbottoms consistent rules. I hope.





Regarding damamge, I've taken a metal scraper to hard growth in some extreme cases. As long as the scraper is not sharp and the corners are rounded, it's not too dangerous, even to barrier coat IME. But as a regular practice, I think the result would eventually be different. Would you take a scraper to your topsides, with force, and not expect some gouges and wear over time? And some boats have pretty thin skins over the core.

Well I guess the short answer is no to scraping the top sides but I also have NO bottom paint there...OR marine growth.
So, the question really doesn't apply here.
And it's not a cored hull.
Boatyarddog