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Do a read around some of the other forums and find out about the many people who have had problems with copper based antifoul "disappearing" within months of application.

 

Assuming the hull is epoxied (and many are not) then the effect will be reduced. But it only takes one salt water contact with the armature through a fissure in the cement or a crack or chip and voila! we have a battery.

Yep, understood, and cant argue with that. That would complete the circuit, but faults in any boat can cause major corrosion issues.

I dont think copper anti-fouling would help!! I also don't think there is currently a great antifouling solution available to the average boatie....Certainly none I have used are spectacular.

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Its all about what you want and can afford. I don't think many people decide on a ferro purely on a performance basis, i.e sailing ability, durability, looks etc, I think most buy a ferro because they

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Dunno who this is aimed at. I'm a retired electronics engineer, I'm pretty sure I know how electricity works by now. 8^]

Sorry dude, I don't have ESP. But also, just because you are an Electrical engineer does not mean you understand. I have met many Marine Sparkies that don't understand Galvanic corrosion and Electrolysis. However, I will assume you do understand.

 

 

Do a read around some of the other forums and find out about the many people who have had problems with copper based antifoul "disappearing" within months of application.

Very likely due to a completely different issue. First of all, where on the nobility scale is Copper and Steel and then consider on the scale where Zinc is in relation to Steel. Why do they use Zinc as a sacrificial Anode?? Because it is less noble than Steel and sacrifices itself first. Because Copper is more Noble than Steel, the Steel would sacrifice itself trying to protect the Copper. When this does happen, the result is that you get patches of steel eating away and those patches are shiny looking jagged craters while in the water. The patches will rust in minutes when you lift the boat out. A fault often seen on Rudders made from Steel plate, they fast become similar to Swiss Cheese.

But that is just one of the reasons why you fit an Zinc anode.

Now in saying that, there is one way that a coating can be blown off a Steel Hull. And that is due to a major Electrical fault causing electrolysis. That (as you will know) is different to Galvanic action. The Fault could be on a Boat berthed beside or the Pier or the electrical supply etc etc. If barrier coats are used, they will often bubble away from the surface it was once adhered to.

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Yep, often happens due to welding on an adjacent boat actually. I'm also reliably told that the best way to sink a steel ship is to drop a penny in the bilges, it will eat a hole clean through.

 

The end result - for me at least - is the same. I don't want to use such an unreliable product, especially if it requires pre-coating the hull with expensive epoxy to avoid causing the armature to corrode. That would be over-capitalization on a grand scale for a ferro, and you'd never see a return for it. And even if that treatment is entirely successful, a path via bronze thru-hulls to the angle iron of the engine mount is almost impossible to avoid.

 

In summarizing the alternatives, though, it appears there's nothing much else that works. So my policy of just scraping the damned things periodically wasn't so silly after all. Paint just "prettyfies" it.

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Sorry dude, I don't have ESP. But also, just because you are an Electrical engineer does not mean you understand. I have met many Marine Sparkies that don't understand Galvanic corrosion and Electrolysis. However, I will assume you do understand.

 

 

Wheels, you don't even seem to know the difference between an electronics engineer, an electrical engineer and an electrician. I know you try hard though, so no hard feelings.

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 Dude, how about getting off your high horse and consider that maybe you are not the expert you think you are. I am highly qualified backed with a lot of experience. You keep making comments that are full of error. Like the Bronze through Hulls part 2 posts back. By the way, what does your prop happen to be made from? Over capitalization? a few hundred bucks worth of epoxy is over capitilzing huh. My Boat has a value that makes a bit of epoxy way worth the cost.
Re you post immediately above,

There is only one thing in life that I despise. People that Patronize. I am actually very qualified myself and understand this stuff far more than I think you appreciate. I am trying to be nice and explain something to you without myself being patronizing. But hey, if you want to consider yourself an expert when very clearly you do not understand, then by all means you go ahead and do it your way. For me, I will continue to us a copper AF and enjoy the clean Hull it provides, as it has done without any issues since it was launched back in 97. And I will also rest easy knowing all the Steel Boats out there that get copper based AF's applied every year with no issues, will continue to do so with no issues.

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Far more qualified people than either of us - Colin Brookes included - advise against wasting money on epoxy coating the hull, and against using copper based coatings. I rest my case on that point.

 

You deserved the last shot. A "sparkie" is the name for the low man on the totem pole in the electrical business. He's usually a guy who learned via apprenticeship and has some basic night school in electrical matters. You'd hire that guy to install wiring in your house. Of course he doesn't know anything about this, he isn't trained to know it.

 

That is a far cry from either an electrical engineer (which I am not) whose focus is on electrical generation and distribution systems, or an electronics engineer (which I am) who designs, builds and repairs radios, computers, electronics control devices, surface mounted components that have to be worked on under a microscope, audio and video system, industrial lasers, printers and a host of other complex products.

 

Since you have no idea of my background and I have none about yours, I'll take your word about your "high qualifications" but I can almost guarantee they don't come within a bull's roar of my experience, if for no other reason than lack of opportunity.

 

But that whole pissing contest is irrelevant, since this is entirely about justifying your choice to epoxy coat your yacht and apply copper coat to it. Go right ahead, but from my viewpoint it's a waste of money. And when the value of a ferro yacht is so low (the one I'm in now cost $2000) then a mere several hundred bucks worth of paint does indeed constitute overcapitalisation.

 

It's a small mind indeed which can't tolerate an alternative viewpoint. After all, there are as many of them as there are people on this planet. Get used to it.

 

And before you come back a-blustering some more, go look up the Dunning-Kruger effect.

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I'm not getting involved in the copper coating debate because I'm not intending to do that and I cannot speak from a position of any real authority/knowledge (so i'll keep it shut).

 

With regard to protecting your hull - whether it be epoxy or chlorinated paint ...I would only add this to the mix. My understanding is that ferro cement, whilst being waterproof if mixed/delivered correctly, can and does suffer from a loss of integrity........

 

'Concrete exposed to marine environment may deteriorate as a result of combined effects of chemical action of seawater constituents on cement hydration products, alkali-aggregate expansion (when reactive aggregates are present), crystallization pressure of salts within concrete if one face of the structure is subject to wetting and others to drying conditions, frost action in cold climates, corrosion of embedded steel in reinforced or prestressed members, and physical erosion due to wave action and floating objects'.

 

 

And that's presuming that a plastered hull was laid up perfectly with the exact/perfect  mix, sufficient armature covering and curing, no voids, never gets scraped or dented etc.. However, in the real world, as we all know this is not the case. When we quote Colin Brookes (as we all do - including me!) I think we should remember that he tends to write from the laboratory and also that some of the things he says do not always chime as  correct (with me).

 

ultimately, as Haiqu says, it's up to the individual to make their own decision and pay their money and take their chances. 

 

I'm intending to keep my concrete lump for the next 10-15 years. The cost of epoxing it will be around £175 which I will be doing...even nif it's only to make me feel better it's a small price to pay!

 

We'll see how it turns out!!!!!! (in a few years). 

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And before you come back a-blustering some more, go look up the Dunning-Kruger effect.

Big call as that could apply equally to you or Wheels..... or neither.

 

Just saying it could indicate D-K in action. It's far from unknown for industry professionals to suffer it due to not being up to full speed with the latest thinking, theories, techniques and etc. I see it often with people in my game. Most only think it can apply to laymen but then that is a form of D-K in itself.

 

Not saying anyone is or isn't here, I could but I'd need a couch and at least $250 per hr :D. Just using some of my newly acquired knowledge in the real world cause I can and it's lunch time on a day dominated by over head sanding and glassing, yes I'm procrastinating. I'll get the Prof to check this next week to see if I've done a D-K myself with this post.

 

On a interesting side note, D & K came up with the theory after observing a dude coincidently named Wheeler. He thought he could make himself invisible and rob banks, he couldn't. There are some who think what D & K saw was simply a case of good old school dumbarse, not the D-K effect but Mr Wheelers strange actions are now the accepted story on how the D-K effect came about.

 

I've gone back to school to see if I can make more sense of some of BP and MB's posts. They love using big words.... often when smaller simpler ones would be the better option. There's a name for that as well ;) But it is very interesting stuff all these Dunning Krugar effects, Eisegesis's and the one that started the quest for this knowledge, cognitive dissonance. My fav at the moment is Cotards or what some call Walking Corpse Syndrome, especially after a women in the US recently suffered from it. She managed to get her family to all but bury her, it was bizarre and seriously fascination stuff.

 

I didn't realise just how fecked up all of us really are :D

 

Carry on................

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Interesting issue that has been well investigated,  https://darchive.mblwhoilibrary.org/bitstream/handle/1912/191/chapter%2022.pdf?sequence=31

 

"PRACTICAL CONSIDERATIONS It seems clear from the foregoing discussion that, on steel construction, accelerated corrosion may be expected if paints containing either copper metal or cuprous oxide are applied unless adequate barrier coats are employed. If the coating contains metallic copper as a pigment, and the barrier coat is inadequate, more serious pitting may result at holidays or breaks in the paint surface. The protection afforded by the paint against fouling wil be decreased whenever the cónditions lead to increased corrosion, and this may, in fact, be a more serious consequence than the damage to the steel or the destruction of the paint film by corrosive action"

 

But in practice on a small steel vessel that is protected by an appropriate epoxy primer it is manageable.

 

Running total thus far

 

Haiqu 1 Because he is correct that they have a negative effect.

Wheels .5 Because he is also correct but not for the right reasons

KM 0 because that's all he gets on the Dunning Kruger metallurical scale

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