Oxidisation of Coppercoat

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TimfromMersea

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I'm continuing to have problems with the Coppercoat applied to my boat. It was applied in late summer 2006, and then abraded in the summer of 2007 as it hadn't really worked at all well as an antifouling.

The boat was launched in March this year and when she was hauled and scrubbed in June she was quite fouled.

The boatyard are having her out of the water next week and are abrading the bottom again, but the essential problem seems to be that the Coppercoat has not turned green, and is still the unreacted red colour it was when it was applied. According to Coppercoat, it needs to turn green, i.e. oxidise, before it works.

What I can't understand is why it has not turned green! Has anyone out there got enough technical chemistry knowledge to advise why the copper has not oxidised in sea water?

Any information gratefully received!
 
First guess is that the abrading might not have been thorough enough. Once applied, the epoxy paint must be rubbed down enough to expose the copper.
 
When you abrade it, is there copper coming off or just epoxy?
Sounds like copper not exposed, through incorrect application?
The copper should discolour a bit before launch, as an exposed copper pipe would.
Could the copper powder have been oxidised? is it brown like an old pipe or colour of polished copper?
 
Thanks for the advice.

It was applied by a very highly regarded (and highly charging!) boat yard that was recommended specifically by Coppercoat following problems with it earlier and which they put down to incorrect application, and so there is, I believe, little chance that it was incorrectly applied.

It may well not have been abraded enough - the same yard did it, I wasn't there. Hopefully when they haul it next week and abrade it again, this will resolve this possibility.

At the moment it is a dull, sort of dark brick, red. If I knew how to I'd attach a photo!

Thanks again for any advice that anyone can give.
 
Ours was applied 11 years ago - so can't comment on how long it took when new. However, each year when we haul out I mix up a little bit and touch in any areas where it has flaked off or looks thin - this is always a pinky colour when applied, but after a couple of months in the water goes green.

This is how our 11 year old Coppercoat looked when hauled out at Easter - you can see the pink patches we touched in:

Groundplate.JPG


It does seem to get a thin layer of slime developing quite quickly - ours has been sat for about 12 weeks now and has a slimly look to the rudder and around the waterline - will wait for some clean water and get in there with a scotchbright pad and a snorkel!

We didn't abraid ours last season and it wasn't too bad when hauled out - although when nice and clean after launch you sure can tell the difference!!

Jonny
 
We had a very similar and unimpressive experience. The job was professionally done and I was there when it was done. Everything by the book - well the video actually.
After the first season it came out looking worse than if we had used regular anti fouling The people at CopperCoat were very helpful but the advice was abrade it some more. Also that we should expect to haul out and scrub during the season - this is a serious cost that destroys the economic argument for using CopperCoat.
We did the abrading before we went back into the water this season and await developments, though a quick visual inspection last week does not inspire confidence.
My problem is how much can you abrade it before there is nothing left and we are back to using regular anti foul?
I would find it hard to recommend it based on my experience - it is not cheap, takes a lot of work and is a long term investment that does not look like paying off.
Sometimes I get the impression that there is an air of 'The kings new clothes' around this product.
 
[ QUOTE ]
If I knew how to I'd attach a photo

[/ QUOTE ] Eazy peazy

The comprehensive tutor is HERE but its a lot simpler than it looks.

Basically upload a picure to Photobuket using the upload options to get the size right (See the sticky at the top of every forum index).

Click on "IMG code" below the thumbnail you get to auto copy that to your clipboard then just paste it into your post.

Lemon squeezy! /forums/images/graemlins/grin.gif
 
I'm in my 4th season of using Copper coat and I have to say I tend to blow hot and cold over its use. However, although we do get weed and slime on the hull, we never get crustacheans. We have never abraded the hull since it was applied. Copper coat told me that the epoxy gradually degrades at about the same rate as the copper(?). Mind you the epoxy seems so hard it is difficult to rub through to a new copper shine. Pressure washing off the hull twice a year is no real big deal if one of those times you dry out and the second time you take advantage of a summer lift deal over a weekend.

I believe, although I have no scientific evidence, that with water like that in our marina, where there is a high proportion of fresh water the CopperCoat is less effective. Last summer, with lots of rain running off into the marina, was a lot worse for weed growth than years when there was more sun. Also, the more the boat is used the better it survives.

As to the question posed by the OP'er, ask the 'professionals' who applied the stuff and abraded it why it is still brick rather than green, tell them to get the job done properly.
 
If you get the boat out of the water, is there a preparation that will accelerate the oxidisation process? Strictly speaking the green colour is copper carbonate not copper oxide which is black. I am not sure what in sea water is going to cause Coppercoat to go green (Any chemists here).

It looks to me as though we need a catalyst to get the green to form, if that is what is needed to prevent growth the process to work(Any confirmation?). Any suggestions as to how we could accelerate the process? It would also be great if we could wipe the hull with an impregnated rag, and easily identify areas where have not been opened up.

Any suggestions?
 
[ QUOTE ]
Any suggestions?

[/ QUOTE ]Dilute Acetic Acid (common white vinegar will do) to form an acetate film which will deter the weed and crustaceans.
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Artificial Intelligence is no match for Natural Stupidity
 
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