Copper based antifouling

my experience so far is it is fine in cold waters but not so good in warm waters,there are a couple of posts running about it at the momment,
i would say at the momment no really clear conclusion,but the more input we get maybe a more informed decision can be made,
 
Having worked in the industry for the best part of 30 years the info I have on long life Copper A/f is that unless the surface is "stimulated" by rough bristle brushing or by rubbing down at regular intervals, fouling will attach itself to the hull. I have had to clean off some of the Epoxy copper coatings with a spade before I could take hull readings!
 
I bow to the experience of others. My Coppercoat in Greece did not show any vegetable or animal fouling for the first four seasons and then only a hundred small barnicles in the fifth season. The boat was in the water at the height of summer for between four and eight months.

I think those with experence of many different systems might have more knowledge. I would guess application technique etc has a lot to do with the performance.
 
The boat was in the water at the height of summer for between four and eight months.


hi scarlett,did you polish your coppercoat regularily to expose the copper as i assume by the above that you had her lifted out each year,and were you on the move alot of the time,i'm wondering whether being at anchor or in a marina makes a difference to the effectivness of coppercoat
 
Our copperbottom has been on for 11 years. This year we forgot to abraid it before launching (first season with the boat!). We have some growth on the water line (rubbed off with deck brush) and the rudder appears to have some. However, this said, I dived on it in the summer and it appears to be only weedy in areas where the sun can get to it (rudder etc). The rest of the hull just has a thin layer of slime.

The boat has been in the water since March, but has mostly been marina bound (2 weeks sail at easter, 5 weeks this summer - but nothing between). Considering this it has simalar / less weed than conventially antifouled boats in the marina - not bad for 11 years old and not abraided!

Jonny
 
I'll start by declaring an interest. I make one of the copper based antifoulings and I've been in the marine paints business for more than 20 years so hopefully have picked up a little knowledge!

Copper based antifoulings work in all water temperatures and locations - but not always perfectly. They can be affected by environmental factors - usually water quality - or occasionally just be overwhelmed by quantity of fouling trying to grow.

There is no such thing as the perfect antifouling for all locations - unless they are so dangerous you wouldn't want to be near them. All can fail but most work most of the time. The reason copper is gaining interest is because the boosting biocides used in conventional antifoulings are being whittled away by legislation so they become progressively less effective.

We have examples of customers spending extended periods in very warm climates with excellent results. I have to admit we have also seen some with fouling problems, but they were usually as a consequence of being in places where the water quality was not good.

We have test panels at an independent research station in Southern India where water is very warm and fouling very aggressive. After nearly 2 years they are completely clean.
We are also about to apply to a pipeline carrying oil at 85C for an oil company who are happy with performance at high temperatures.

Most copper based products use copper dust mixed with a resin - usually an epoxy - and applied in multiple layers. This means the copper is distributed through the coating and you will need to abrade the surface periodically to expose fresh copper as each layer is exhausted. If the surface is not abraded you will be left with only epoxy on the surface and it will foul.

As Scarlett says, application technique is critical to these systems and most problems are as a result of poor dispersion of the copper during application.

We insist on professional application for our system and all the copper is embedded in the surface so it does not need abrading and cannot suffer from poor dispersion at application.

Copper antifoulings work by a complex mechanism, and there is no doubt they are best if left permanently immersed. If you take a boat out of the water for any length of time do not expect the antifouling to just start again automatically with no maintenance when the boat is launched. While maintenance is important it is also very simple.

Copper works just as well whether moving or static except that you will usually get more slime in static water. Water flow doesn't really affect the erosion rate of the copper either except in extreme turbulence so working life is not affected.

Copper has been used as an antifouling for hundreds of years but went out of fashion when strong chemicals were introduced (and when you could no longer nail sheets of copper to boats).
It is coming back into fashion as the strength of chemical antifoulings reduce and we develop methods of application that don't put holes in boats!

Hope this all helps
 
[ QUOTE ]
If you take a boat out of the water for any length of time do not expect the antifouling to just start again automatically with no maintenance when the boat is launched. While maintenance is important it is also very simple.


[/ QUOTE ]

How would you suggest maintaining the copper coating when launching the boat after 3 / 4 months out of the water over the winter? I was told a light abrasion with a scouring pad or simalar to bring the copper back to the surface?

Thanks

Jonny
 
Hi Jonny
Just read your thread on this subject.

For your antifouling you are exactly right if the initial application was good - which it must have been to last so long.
Abrading exposes fresh copper and also removes the greasy pollution film that will be on the surface as a consequence of being out of the water for so long.
Some people find a scouring pad adequate but others need to use wet & dry paper.

Your trip looks fantastic and well organised. I will follow with interest and envy!
One reason to choose copper is no worries about where and how to lift out, compatibility of antifouling etc.
 
Thanks! Hoping that with some good abraision before launching next spring we will get more years out of the coppercoat.

Seems to have been well maintained - there is a small kit of Coppercoat in the locker and previous owner applied this to areas where the original was thinning or flaking thus keeping quite a good thick layer over the whole hull - seems to have worked well so far. I'm impressed with performance this year given she was out of the water for 10 months pre purchase and had no abraison pre launch.
 
Passarell sounds authorative. To explain further. When to boat was lifted at the end of the first few summers the Coppercoat would be washed with washing up liquid the same as the topsides. [ Topsides waxed afterwards prior to winter].The last time, it was lifted from mainly salt water, the 100 baby barnicles were removed with a credit card and then, this year, some 1200 wet and dry paper run over the surface before the launch. A half hour job.

The boat spent about a week in salt water this year - the rest of three months in mostly fresh water.

Nothing at all on the hull.
 
hi passarell,you seem to have cleared up a few points, i think my problem stems from more abrasion needed or possibly water quality in the marina,i am removing the barnacless at present then going to try and abrade the surface more,i definetly seem to have more problems in the med eg barnacles than i did in cardiff,spain portugal where i only ever got a thin layer of slime,but its possible they didn't have many barnacles about,there.the idea of the long lasting no liftoout etc was what appealed to me ,and up to going in the med all was fine ,
 
Hi Orizaba. Barnacle spat tend to settle in the spring when most antifoulings are still at their strongest soon after launch. The spat also seem to swarm (my opinion based on observations) in that they will colonise one boat and leave others with the same antifouling alone. Having said that they will go for the "softest" target when possible. Copper antifoulings operate at a similar level throughout their life without that initial peak strength.
Scarlett says he removed them with a credit card which I see as a positive for copper. They would take a lot more than that to remove from most antifoulings! If copper does get fouled it is usually only lightly adhered and easy to remove.
If the water in your marina is polluted it may well contribute to the fouling but your problemit is more likely to be lack of abrasion. The epoxy resins usually used to hold the copper are quite hard and while you may get away with a scourer for a while they will need to be taken back properly to expose fresh copper sometimes. The 1200 grit Scarlett mentions seems a bit fine to me. If you haven't done so before I think I would use 200 - 300 grit every few years with scourers in between but that's just my opinion.
 
thanks for the answer pasarell,the ones i have come of with a light scrape,bit more than a credit card tho,i think i was spoilt / luckybefore and did not realize the amount of exposure really needed,will persevere and see what happens,
best dig out my frogmans mask and flippers
 
Any of you who followed the post by Jonny_H on SB will have already seen my post on the subject, but for those who didn't here it is:

"The application of copper based antifoul is all important. Both my friend with his Hanse 371 and myself have Coppercoat. Both boats are in the same marina in Chi Harbour.

Hanse 371: professional spray application, curred with heated lamps undercover. - Poor performance, lots of weed.

Same Hanse, strip at water line to extend height and keel re coated after repair, both done outside in borderline conditions - both areas working well.

ETAP 35i: applied by us, outside well within climatic limits - works OK no crustacous growth but some weed and slime.

What we have concluded is that the 'professional' application with heated lamps has cured the epoxy to hard. Our own boat where the epoxy also cured well is difficult to abrade, its too hard.

The Hanse 371, where the coating was applied in borderline conditions, the epoxy is softer and can be abraded. The keel on the Hanse was completely clear of any growth when she was scrubbed early this month.

So to summarise, the harder the epoxy the poorer the performance. DIY application is better than pro, but don't do it mid summer, its too hot! Apply just within the climatic limits. All other application criteria must be adhered to, IE clean dry hull free of ALL old antifoul, degrease etc and the epoxy/copper/curring agent mixed well using a mechanical means."

Pasarell, am I correct in thinking that your product is Cuprocoat or similar, like the one that Dick Durham has on Powder Monkey?

Our Coppercoat was applied over two coats of ME100 epoxy, it was applied the following day so is well 'glued' on, trouble is the surface is orange peel, so wet and dry only abrades the high points! A Scotch Brite pad will not touch the epoxy, it is too hard!

I have seen someone from a company based in Cornwall using what looked like an old fashioned cotton mop, but it was synthetic and was covered in some abrasive substance, it was fitted to a an electric polisher at about 1000rpm. This he used with a rubbing compound. That process made the copper look like your grannies copper kettle!

I have this year used regular antifoul on the high weed growth areas, rudder and under the forward sections of the hull. These are the areas where weed growth was worst.
 
Hi Galadriel. My product is Cuprotect and it is what DD has on his boat - a case where the maintenance procedure wasn't done when the boat was out of the water for several months.

I think you are making several assumptions that aren't necessarily correct. Amateur application better than professional, don't apply in mid summer etc.

If the epoxies aren't fully cured they will certainly not last their expected life. Some epoxies can be formulated to be harder than others when cured and this would certainly affect ease of abrading but this is not a function of temperature during application or curing.

I've seen good and bad applications from both professional and amateur jobs. A lot hangs on keeping the copper in suspension throughout application. You correctly mention keeping within all the other parameters of surface preparation, climatic conditions etc.

Epoxies are usually quite high build - they form a thick film - and so are prone to orange peel. I hadn't considered this before but it will affect rubbing down, especially if it is a hard epoxy when you will only touch the top of the peel with a scouring pad.

Despite epoxy being high build it is still really quite thin so any mechanical abrasion would have to be carefully done to avoid going right through to the gelcoat. Also any rubbing compound would have to be thoroughly removed to avoid a film left over the copper that may block it from working. I suspect the one you saw may have removed more of the epoxy than necessary if it polished the copper. The green patina that forms over copper is the active part when immersed and doesn't need to be removed.
With Cuprotect we spray copper into the surface of the resin so it is all on the surface and doesn't need abrading. We also use copper nickel rather than pure copper to harden the metal and control the leaching rate.
 
Sorry, got the name slightly wrong, Cuprotect is what I meant.

You say:

"The green patina that forms over copper is the active part when immersed and doesn't need to be removed."

That's copper oxide, isn't it? Although we haven't yet found a way to polish our hull to reveal fresh copper, the surface after pressure washing is green and apart from slime, we get no barnicle type growth.
 
This is my experience with it:- coppercoat thread and pics It was professionally applied over 2 coats of epoxy, worked OK for first 3 years but doesnt seem to work anymore. Abraded hull with wet and dry back in April this year but look at the pic of the "shredded wheat" growing all over hull, apologies for crappy pic, it was on mobi
 
Hi Galadriel. Copper oxidises in contact with the air to give a matt brown colour compared with the salmon pink colour of fresh copper (think of plumbing at home).
When it goes in the water that copper oxide reacts to form copper hydroxychloride which is the green patina you see. In fact the colour can vary from light grey (usually in cool brackish water) to almost black but always with a tinge of green. Colour is affected by temperature, salinity and other constituents of the water but it is that film that gives the antifouling properties. In the UK the colour of our product is usually a mid green.
Preventing slime is the holy grail for antifoulings so you have to expect it I'm afraid. Barnacles are normally stopped by copper but, as I said in an earlier post, it's not magic and it's strength cannot be varied so occasionally is overwhelmed by a strong attack.

Out of interest copper is also good at stopping the hospital superbug MRSA. Apparently the bug only survives for a few minutes on copper compared with days on stainless etc. A hospital in the W Midlands is starting an experiment with all equipment made from copper on a ward to see the effect.
Silver works even better as an antifouling but the price goes up a bit!
 
First of all I would like to declare an interest, as we are the manufacturers and suppliers of Coppercoat.

We, as a matter of course, monitor various forums for discussion of our product but have until now made the decision not to respond, as we believe web forums should not be used as a marketing tool.

However as our product is becoming more and more commonplace, a number of threads are being started by people looking for technical advice with regard to boats that already have the Coppercoat anti-fouling system. We have therefore made the decision to respond to some of these points to save people from well meant but misleading or inaccurate answers/advice.

A much debated point is whether or not Coppercoat needs abrading annually. The simple answer is that this is not usually necessary. We have many customers who have Coppercoat treatments that are over ten years old which have never been abraded. For example, “Zest” owned by the Norbury family (Sarah Norbury being the current editor of PBO) which we initially treated in 1993, is in the water (at the Hamble) all year round, only coming out annually for a couple of hours for a routine inspection. Nothing more than an annual pressure wash has been required in the last 14 years, in an apparently “high-fouling” area.

That said, a small percentage of our clients have found it beneficial to lightly burnish their Coppercoat. This burnishing should only be done using a fine grade of wet and dry paper (600-800 grit), a scotchbrite sanding pad or similar. The idea is to polish the surface - you are not looking to sand the Coppercoat, or to remove all of the green patina which as “Pasarell” (is that you, Peter Sims of Eco-Sea?) points out is an active part of Coppercoat. Any coarser grade will only “score” the surface, which might enable marine life to gain a hold. Coppercoat offers an exceptionally hard surface and this burnishing will not degrade the life of the product. In line with our application instructions, we recommend that in areas of high fouling treated boats will benefit from a light burnish after the initial application of Coppercoat, prior to the first immersion.

As with all anti-fouls, the performance of Coppercoat may vary from location to location and boat to boat. Consequently there can be no set rule when it comes to maintenance. While some boats will stay clean without burnishing, it is entirely possible that others may need attention from time to time.

Coppercoat is a simple product, based on the idea of using epoxy resin to attach copper to the hull. We use 99% pure copper powder in Coppercoat because over the last 16 years we have found this to provide the strongest anti-fouling properties and the longest effective life. Trials with copper-nickel showed a slower production of active cuprous oxide and consequently weaker anti-fouling performance. Importantly, the clever and truly unique part of Coppercoat is our specially designed epoxy resin. This breaks down at approximately the same rate as the copper and therefore provides a constantly refreshing anti-fouling surface. This is the main reason why annual sanding is not necessary in most circumstances. Of course, there are times and conditions when the rate of degradation of the copper and the base epoxy differs, and it is then that pressure washing and/or burnishing may be required.

Another point that raises many questions is application. Coppercoat is designed to be a DIY product. Most of our customers in this country are boat owners applying the product to their own boat. As “Galadriel” points out, with any job preparation is important and as Coppercoat is a permanent epoxy coating, it must be applied to a suitable substrate - for example, clean and abraded gel-coat or epoxy. Full details for application can be found on our website but as a “rule of thumb” if the weather is suitable for general painting (i.e. dry and warm), you can usually apply Coppercoat.

With regards to higher temperatures causing problems with curing, we currently have distributors in 16 countries around the world, not including the customers we supply directly. The ambient temperature in some of these areas (e.g. Dubai, Kuwait, Turkey, Australia, etc) is considerably hotter than here in the UK. This causes no problem to the application.

When using Coppercoat the copper must be kept in suspension. This is normally achieved by simply stirring the mix, as and when you go to top up your roller tray. We do not recommend mechanical mixing, as whisking the product with a drill is not beneficial. A bucket and stick is the only equipment required to mix the product correctly.

Finally please note that this advice is for the benefit of Coppercoat users. Since launching this product (and indeed inventing the genre of long-life copper-epoxy based anti-fouls) back in 1991 (when Coppercoat was known as Copperbot) several “similar” products have been available. Consequently although statistically unlikely, it is possible that some forum readers will have systems such as Copperclad, Copperbot 2000, CopperGuard, Cupro-FF, Cop-R-bot, Cu-17, Halcyon 5000 or Royal Copper. While some of the advice contained here may be applicable to owners of boats with these discontinued systems, we can not be held responsible for these products or their performance.

I hope that this general information proves useful.

I will sign off by stating that it is not our intention to be a regular contributor to this forum. For those of you with questions about the application, use and maintenance of Coppercoat please contact us directly for the most technically accurate and knowledgeable advice. Having supplied this coating to over 30,000 around the World boats over the last 15 years we should know the answer to your question!
 
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