Copper Coat on an Alu hull - yes or NO ?

[Kit_L]

What about a completely different approach? I have been thinking about silicon-based release paints, rather than anti-fouling.

I first read about these on the https://mobius.world/ site (they used Intersleek 1100SR
Advanced Fluoropolymer Foul Release Coating) and found a YT video here that talks about a Hempel product:

https://www.youtube.com/watch?v=GiVx7G_gCwc

Shows promise, I think.

[Del Mare]

"

Originally Posted by s/v Jedi

A very bad idea. Imagine building up 5-6 layers of barrier coat just to be able to use an incompatible antifouling

Use an antifouling for aluminum boats. Make sure you have an isolation transformer for shore power and have a silver chloride reference cell aboard for regular checks (available from boatzincs.com). I have met aluminum boats that have a permanently installed system with alarm function.

"


Hello, I'm going to build a 45-foot aluminum sailboat and I was very interested in this alarm system you mentioned. Can you tell me where to get this system?
Thank you very much for the information and happy sailing!

[Franziska]

If you go down the path of Coppercoat, which I personally do not consider clever on an Aluminium boat, make sure to extend your barrier coats well above the waterline.



Also, be sure to never fall dry on a sandbank and never hit something with the bow.

Sometimes there are rocks on sandbanks which can crack a barrier coat. Sometimes one might hit some floatsam...

[GordMay]

Greetings, and welcome aboard the CF, Del Mare.

About Corrosion Surveys ➥ https://www.google.ca/url?sa=t&sourc...DMJRriuDUPFJ2k

You can perform a corrosion survey, yourself, with a portable, analog unit, such as the ProMariner Corrosion Test Meter [# 20006-1]. They are millivoltmeters, with a probe, that is attached to the metal, and a silver chloride half cell, that is thrown over the side of your boat, and immersed in the water. The readings will tell you, very quickly, whether the metals on your boat are being eroded, or being protected. This simple test can also tell you if you are over, or under zinced.


A permanently installed corrosion monitor is useful for instantly detecting stray current, in a marina.

ProMariner Deluxe Corrosion Controller [Part # 20020]
➥ https://www.promariner.com/en/p/2002...ion-Controller

Electro-Guard Model 126A - Cathodic Protection Monitoring Station, for Aluminum Hulls
➥ https://www.boatcorrosion.com/product-126.html

More Electro-Guard products ➥ https://www.boatcorrosion.com/system-instructions.html

[dlj]

It's my understanding that a number of new high-end aluminum hull boats are using Impressed Current Cathodic Protection (ICCP). It's an excellent system for corrosion protection. It's been used for a number of years in pipelines, where it's initial commercial application started IIRC.

It is not something you want to develop yourself on your boat. You should really hire a professional if that is something you want to pursue. Several of the links Gordmay posted above point to components that could be used in an ICCP system. Monitoring is one thing, not a bad idea, but I'm not sure what it is really doing for you other than, oh crap, something is going on... I guess at least it can give you an early detection system.

If I had an aluminum boat, I would go through the process of setting up an ICCP system. If doing so, I would definitely use a professional with documented experience in that field.

This is perhaps a bit of thread drift from the OP's original question if they should use coppercoat as an anti-fouling. But, I feel the OP should be looking at a more holistic approach to their hull. What do they have currently for cathodic protection on their hull? How will the coppercoat bottom paint affect that? Then look at if that is an appropriate anti-fouling for their boat. I don't think seeking the "wisdom of the forums" is the best way to know in this case. None of us know the full picture of the OP's boat and it's existing systems. Aluminum hull boats are excellent - but they can also be compromised rather quickly.

Just my 2 cents worth...

dj

[Del Mare]

Originally Posted by GordMay

Greetings, and welcome aboard the CF, Del Mare.

About Corrosion Surveys ➥ https://www.google.ca/url?sa=t&sourc...DMJRriuDUPFJ2k

You can perform a corrosion survey, yourself, with a portable, analog unit, such as the ProMariner Corrosion Test Meter [# 20006-1]. They are millivoltmeters, with a probe, that is attached to the metal, and a silver chloride half cell, that is thrown over the side of your boat, and immersed in the water. The readings will tell you, very quickly, whether the metals on your boat are being eroded, or being protected. This simple test can also tell you if you are over, or under zinced.


A permanently installed corrosion monitor is useful for instantly detecting stray current, in a marina.

ProMariner Deluxe Corrosion Controller [Part # 20020]
➥ https://www.promariner.com/en/p/2002...ion-Controller

Electro-Guard Model 126A - Cathodic Protection Monitoring Station, for Aluminum Hulls
➥ https://www.boatcorrosion.com/product-126.html

More Electro-Guard products ➥ https://www.boatcorrosion.com/system-instructions.html

Thank you very much GordMay!

[Jim Jones]

Old thread but updating as i see new posts to the thread.

I decided not to go with the coppercoat. I feel like I got really bad advice from the yard who tried to get me to go this way - they insisted they do all the work on boats in thier yard - so I left thier yard and had the boat towed to another place to do the refit. Ended up purchasing Trilux 33 from International - its really the only anti foul to use on aluminium hull - no traces of copper at all

[Panope]

Originally Posted by Jim Jones

Old thread but updating as i see new posts to the thread.

I decided not to go with the coppercoat. I feel like I got really bad advice from the yard who tried to get me to go this way - they insisted they do all the work on boats in thier yard - so I left thier yard and had the boat towed to another place to do the refit. Ended up purchasing Trilux 33 from International - its really the only anti foul to use on aluminium hull - no traces of copper at all

Jim, it appears that Trilux 33 does contain a form of copper:

"Trilux 33 offers highly effective antifouling protection from a combination of two agents: aluminum-safe copper I thiocyanate, and an improved version of Biolux® (3.4% zinc pyrithione) anti-slime technology."

However, Micron CF (also from Interlux) appears to be truly copper free:

"Micron CF (Copper Free) is a multi-season, copper free antifouling that uses Biolux® Slime Blocking Technology to repel slime and Econea(tm) to combat zebra mussels and barnacles. Can be used on any power or sailboat, including aluminum hulls"

[s/v Jedi]

Trilux 33 is 100% safe on aluminum hulls.

[Mal Reynolds]

If it helps, I use this on my aluminum hull:

https://www.epaint.com/product/zo-antifouling-paint/

[Jim Jones]

My International Rep lied to me then - he told me it has NO copper in it at all. Hmmmm. AS Jedi says though it is safe for ALU.

[CaptainRivet]

Originally Posted by boatpoker

Wow! Thats incredible growth for a boat thats always moving. Does that stuff contain barnacle growth hormones ?

I've always had doubts that encapsulated copper powder could be released fast enough to work.

Any theories ?

Coopercoat is nothing else then a waterbased epoxy which dissolves very slowly layer by layer over time reacting with the water and like this expose more fresh cooper over time. Buddy of mine has a chem lab and took Coopercoat appart, he could even figure out the the Spanish company Plainsur and the exact resin used.
It’s made to seal concrete floors in commercial buildings and reacts with it.
Used on boats the concrete is missing to react and that’s why it dissolves very slowly when in contact with water, so basically a hard antifouling combined with a soft antifouling as the Coopercoat just dissolves layer by layer and expose like this the copper.
The art is to have the time layer dissolves to balance with the time cooper is nearly used up, if there is an imbalance that resin is dissolving to slow it stops working.
Typical issues:
First if the application is wrong as not properly mix or wrong rollers for application means too less cooper on the surface it’s too much resin to dissolve means the Coopercoat is not properly working so you need to sand that down till enough cooper is exposed that dissolving and copper exposed is in balance. Then it works for a year and the next application layer again contains too much resin surface and it stops again properly working. If you haul out it’s actually the resin that gets an oxide layer and stops the disolving process.
With activating Coopercoat actually means take away the oxide layer of the resin so the dissolving process can happen.

If you in too warm water which also is also less oxigen saturated this dissolving process slows down… (if cold it accelerates and actually less copper would be sufficient) to counteract you need to put more copper in so that per layer the resin part is smaller. Problem is Coopercoat is already at the limit what’s allowed so officially they cannot tell you to add more. They tell you to sand the hull to activate and blame it on you you didn‘t sand it properly or too long time between sanding and splashing
Well I added 20% more copper, so 1l resin 1,2kg copper, due to my buddies advise and the Coopercoat works really well. On the barefoot route circumnavigate so water will be warm. Also sanding to activate is not so critical as you have 20% more copper so less resin surface you have to sand off the oxide layer so the process is in balance.
Another problem is that often the Coopercoat application is not really dried through before splashing and as soon as in water that process of drying stops immediately. If that application is not really dried through after 3 month till 1 year the Coopercoat starts to malfunction and pieces fall off through the cavitation force of water on the hull. Mine dried 6 weeks before splashing, sanded directly before splashing and no issue then.

[CaptainRivet]

I have Coopercoat on the hulls which really works well but for the saildrives I decided to go for propspeed on the saildrives which is not good at all.
From reading here I still miss which antifouling works for the saildrives well.
Seajet seems to work for 2 till 3 years while trilby once a year
Is trilux what should work for 5 years due to international?

I can service my saildrives without hauling out and also change anodes of the Flex-o-folds so other then defects I just have to haul out to do the saildrives antifouling and looking for what holds the longest. 2 nd the application with primer time need to be done in 1.5days so I can haul in on 2nd day evening so I don‘t have to sand the Coopercoat.
So what to use?

[s/v Jedi]

Originally Posted by CaptainRivet

I have Coopercoat on the hulls which really works well but for the saildrives I decided to go for propspeed on the saildrives which is not good at all.
From reading here I still miss which antifouling works for the saildrives well.
Seajet seems to work for 2 till 3 years while trilby once a year
Is trilux what should work for 5 years due to international?

I can service my saildrives without hauling out and also change anodes of the Flex-o-folds so other then defects I just have to haul out to do the saildrives antifouling and looking for what holds the longest. 2 nd the application with primer time need to be done in 1.5days so I can haul in on 2nd day evening so I don‘t have to sand the Coopercoat.
So what to use?

The only antifouling I ever had that worked five years was one with TBT, Islands 44. I did have Micron 66 for five years but the last two years of that I had to scrape before sailing.

[CaptainRivet]

Originally Posted by s/v Jedi

The only antifouling I ever had that worked five years was one with TBT, Islands 44. I did have Micron 66 for five years but the last two years of that I had to scrape before sailing.

Thanks, really appreciated. 5 years would be awesome and save a ton of money.
Was it the standard or the harder version of island 44? What primer did you use.
How much would i need for 2 saildrives? How long can you store that? Can i put it on the prop too, trilix you apprently can.

Is that the one you mean:
https://budgetmarine.com/catalog/boa...categories_tab

I prefer harder as i don't have very good experience with soft antiouling at all. A fishernet caught in the saildrive/prop will damage a soft antifouling...