DIY CopperCoating application notes.

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This week I coppercoated my keel and rudder as an experiment and training exercise. I thought I would make some public notes for the benefit of others and maybe myself should I do the rest of the hull in a year of two.

Summary:

It is hard because once started there is no option to rest-up or postpone and the epoxy paint is temperamental stuff to work with.

Mistakes Made:

  • Trying to cram the job into a summer special 7 day haul out. After preparation of two days I had a two day weather window for application which did not materialize even mid summer.
  • Epoxy primer paints come in two varieties, solvent and water based. Don't buy the solvent variety unless you can allow for 7 days so that the base layer can vent off its solvent otherwise you risk the coppercoat trapping vapour and bubbling. In British terms this means don't buy GelShield 200.
  • I should have spent a few extra days filling & fairing minor dings in the keel profile because unlike a regular anti foul application I will now have to live with the finish for 10 years.
  • If you want a performance finish then buy 50% more paint that the manufacturer specifies in order to allow for some post application burnishing back to a slick finish. I have noticed over the years that many a coppercoated hull has a stippled finish probably because amateurs are not familiar with the unforgiving handling characteristics of a 2 part epoxy paint.
  • I did not key the epoxy base coat (non coppercoat) enough and as a result the first coppercoat layer did not transfer down well as the roller skidded over the surface. Realizing my mistake mid pot I quickly applied a deeper key with an orbital sander before the pot cured. This would not be a viable correction on a conventional whole hull job.
Tips.

  • There is no option to visit a DIY store for extra supplies mid job, you need all materials for the whole job e.g. 6 paint roller sleeves (not hairy ones) and paint trays and lots of plastic beakers if mixing mini batches. B&Q do calibrated clear plastic cups.
  • The paint is very heavy to mix, think sloppy cake mixture once the mass of the copper is added. A wooden slotted spoon from the galley was the perfect stirrer (need to find a replacement before Swmbo visits).
  • The copper settles very quickly post mixing so stir again every time you top up the paint tray.
  • Unless you have a large application team I doubt a DIYer can roll on a standard 1 liter unit of coppercoat before the pot begins to cure hence you will need something to weigh equal measures of the coppercoat powder. I would pre-bag mini portions of the coppercoat powder at home in heavy duty freezer bags ahead of the job. The copper powder bags supplied are very well sealed probably for health reasons.
  • The dry copper is very fine, think icing sugar or flour. Defo need a top notch breathing mask when handling this stuff and shelter from the wind.
  • I reckon a DIY team should be 3 strong, one mixing, dispensing and re-stirring, the other two rolling on.
  • The manufacturer of Coppercoat cannot be arsed to specify the max percentage of thinners on the bottle's label which contains mainly cut & paste health and safety wibble. 10% is too much, reckon 3% to 5% is ok. You will need thinners for ease of application and a smoother final finish.
 
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[*]
[*]The manufacturer of Coppercoat cannot be arsed to specify the max percentage of thinners on the bottle's label which contains mainly cut & paste health and safety wibble. 10% is too much, reckon 3% to 5% is ok. You will need thinners for ease of application and a smoother final finish.
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And presumably the OP could not be arsed to read the on line instructions which say:

Thinning:
Coppercoat®
should only be thinned with Iso-Propanol (available from Aquarius Marine Coatings). Always add the
thinners to the Coppercoat®
at the start of the mixing process – never add thinners later when the coating thickens
as this can adversely affect the curing process. For application by roller we recommend that the Coppercoat®
be
thinned by up to 5%. For application by spray it is necessary to thin by approximately 15% to 20%. (Tip – depending
on temperature, we generally add approximately 3 capfuls of thinners to each litre mix of Coppercoat®
, using the
cap of half-litre plastic thinners bottle as the measure.)​
 
Unless you have a large application team I doubt a DIYer can roll on a standard 1 liter unit of coppercoat before the pot begins to cure

Poppycock. I've Coppercoated at least five hulls and it's no bother for one person to roll on a litre before it begins to cure, even in far warmer conditions than you experienced. (I'd always thin it slightly, though, as per the instructions in Vic's post).

Two people is sufficient: one mixing/stirring, the other rolling. On larger boats, say, over 38 feet, you have the option of doing each side as a seperate job.

The best way to avoid the 'stippled' finish you mention (usually called 'orange peel' in the trade) is to spray. It makes naff-all difference to boat speed, anyway. Unless, of course, you're stippled finish was something else.
 
Poppycock. I've Coppercoated at least five hulls and it's no bother for one person to roll on a litre before it begins to cure
That would make you a coppercoating semi pro, my advice is not for people like you.

Two people is sufficient: one mixing/stirring, the other rolling. On larger boats, say, over 38 feet, you have the option of doing each side as a seperate job.
By implication you agree a team of one is too small so you agree with me in part.
 
And presumably the OP could not be arsed to read the on line instructions which say:
I did a lot of pre purchase research, the thinners arrived as an extra with the coppercoat paint. At the end of layer 1 I decided to use the thinners and guess what, mid job under the boat all I could find was the tutorial DVD which I did not have time to study.

Think of it from a customers point of view, having just purchased the most expensive paint on the planet so expensive even a NASA accountant would wince, I discovered the manufacturer could not be bothered to add "Thin by max 5% unless spraying" to the label. The cheapest white spirit in-house B&Q plonk would probably have more help on the label.
 
The best way to avoid the 'stippled' finish you mention (usually called 'orange peel' in the trade) is to spray. It makes naff-all difference to boat speed, anyway. Unless, of course, you're stippled finish was something else.
All those race crews ashore at Cowes or the Hamble laboriously smoothing the finish of their hard anti-fouling know otherwise.
 
1. That would make you a coppercoating semi pro, my advice is not for people like you.
2. By implication you agree a team of one is too small so you agree with me in part.
3. All those race crews ashore at Cowes or the Hamble laboriously smoothing the finish of their hard anti-fouling know otherwise.
4. ...the most expensive paint on the planet so expensive even a NASA accountant would wince, I discovered the manufacturer could not be bothered to add "Thin by max 5% unless spraying" to the label.
5. At the end of layer 1 I decided to use the thinners and guess what, mid job under the boat all I could find was the tutorial DVD which I did not have time to study.

1. No, that would just make my experience greater than yours. Other readers can make of that what they wish.
2. As do the Coppercoat people. It's not a state secret.
3. If you care about the tiniest fraction of a knot, go for it. Most of us, I suspect, don't.
4. Having just purchased 'the most expensive paint on the planet' (you've obviously never bought Awlgrip), a wise man would probably read the instructions.
5. So you were ill-prepared and cocked-up. I struggle to see how that's Coppercoat's fault.
 
1. No, that would just make my experience greater than yours. Other readers can make of that what they wish.
Since you could not be arsed to publish any Coppercoating advice in the public domain the World will continue to be deprived of your infinite wisdom on the subject.
 
Since you could not be arsed to publish any Coppercoating advice in the public domain the World will continue to be deprived of your infinite wisdom on the subject.

This 'could not be arsed' is a popular expression of yours, isn't it?

As a matter of fact I've given quite a bit of advice on these forums about Coppercoat application. I have no control over whether anyone finds it, or even looks for it. For the most part Coppercoat's own instructions are more than adequate, but only providing they're actually read.

But do feel free to try to deflect responsibility for your botched jobs onto anyone who passes by.
 
I did a lot of pre purchase research, the thinners arrived as an extra with the coppercoat paint. At the end of layer 1 I decided to use the thinners and guess what, mid job under the boat all I could find was the tutorial DVD which I did not have time to study.

Think of it from a customers point of view, having just purchased the most expensive paint on the planet so expensive even a NASA accountant would wince, I discovered the manufacturer could not be bothered to add "Thin by max 5% unless spraying" to the label. The cheapest white spirit in-house B&Q plonk would probably have more help on the label.

I doubt it. My white spirit came from Homebase. The label on the front basically says what it is. The label on the back is mostly H&S stuff plus what it can be used for. No further advice on its use. i would expect information about its use , as paint thinner for example , to be in the paint manufacturer's product data sheet.
 
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I applied Coppercoat with my wife and a friend on our 31' boat. I'd certainly agree that it's not a job for one person, and even two might struggle. We had two applying and one mixing, and it went on very well - we rollered it (as advised by AMC for non-professional application), and didn't get the orange-peel effect, though I'd agree that the "orange peel" effect is unlikely to have a measurable effect on boat speed - and could even enhance it (look up the aerodynamics of golf balls and the hydrodynamics of shark's skin). However, AMC advised us in great detail about how to apply Coppercoat, provided written instructions (I think the instructions are still kicking around in my car!) and LOTS of email and telephone support before we decided to buy it. Part of that support included them saying that you needed one person stirring and the rest rolling. So I really don't understand the comments about lack of instructions! It certainly isn't a product where you buy a couple of tins off a shelf and slap it on; it's one that is part of a costly project - preparation actually cost us more than the Coppercoat. I spent weeks preparing to do this job, talking over the requirements with my wife (who did the mixing) and making sure we had everything ready to go. Once we started, it took less than a day to complete; as far as I can see it has been a successful job.

Incidentally, the correct thinner is isopropanol; I strongly suspect that white spirit or anything similar would compromise the result.
 
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Wow, people here get very heated over these discussions.

I have done one 35 foot cat with copper coat in Spain which is pretty warm and I would say its pretty easy to do a litre before it begins to cure but I guess age, fitness, height etc all play a part.

I downloaded lots of instructions first so knew what I was doing but I do agree that in this digital age having CDs DVDs and online stuff is pretty useless when you want to check something whilst under a boat and also wish that companies (not just copper coating manufacturers) would stick to clearly written advice on a bit of paper stuck to the packet or at least supplied with it. Sure I could print off beforehand but I live on the boat and cruise continuously so don't have a printer...
 
But do feel free to try to deflect responsibility for your botched jobs onto anyone who passes by.
I am satisfied with the end result. The job was more demanding than I thought hence my original post. A walk around any British boatyard hard standing in winter will tell a story of DIY coppercoat jobs that hit a bit of application turbulence.

Maybe your antagonistic contributions to this thread are a covert form of personal advertising. Why no update your forum sig to "Coppercoat pro for hire".
 
I applied Coppercoat with my wife and a friend on our 31' boat. I'd certainly agree that it's not a job for one person, and even two might struggle. We had two applying and one mixing, and it went on very well - we rollered it
Pleased to read confirmation that 3 is a good team size.

didn't get the orange-peel effect, though I'd agree that the "orange peel" effect is unlikely to have a measurable effect on boat speed - and could even enhance it (look up the aerodynamics of golf balls and the hydrodynamics of shark's skin).
Hmm I will keep an open mind on this subject until I observe the grand prix racing machines of the Solent applying golfball textured laminate to their hulls :)

However, AMC advised us in great detail about how to apply Coppercoat, provided written instructions (I think the instructions are still kicking around in my car!) and LOTS of email and telephone support before we decided to buy it. Part of that support included them saying that you needed one person stirring and the rest rolling. So I really don't understand the comments about lack of instructions! It certainly isn't a product where you buy a couple of tins off a shelf and slap it on; it's one that is part of a costly project - preparation actually cost us more than the Coppercoat. I spent weeks preparing to do this job, talking over the requirements with my wife (who did the mixing) and making sure we had everything ready to go. Once we started, it took less than a day to complete; as far as I can see it has been a successful job.
I know from your many posts here over the years that you are a highly practical chap and in one sense you have contradicted yourself in your own post. You say you were not prepared to buy or commence the coppercoat application without an extensive dialogue and additional advice. My motivation for starting this thread was to flag up that coppercoating is far more challenging than just a slightly more demanding antifouling job but apparently my contribution to the forum has angered some Coppercoat experts. I should not be surprised after so many years here.

My only comment about deficient instructions from the manufacturer related to an absence of a suggested thinning percentage on the bottle of AMC branded thinners. At an effective cost of nearly £100 per liter I do not think it unreasonable to expect the manufacturer to put a tiny amount of extra effort into enhanced product labeling, which is something other marine paint products include by default.


Incidentally, the correct thinner is isopropanol; I strongly suspect that white spirit or anything similar would compromise the result.
Yes that is the stuff, my thinners has the same Coppercoat manufacturers label as the other pots.
 
When I bought the CC to redo the boat, it came with a DVD showing how to do it plus a leaflet which repeated the information on the website of how to do it (including the info about thinning). Frankly, given the cost and likelihood of not having dealt with resin paints before, I'd expect anyone approaching it for the first time to have read the supplied instructions and brought them along to the worksite for ease of reference. Given the fact that the resin comes in half litre containers by the time you've put the mandatory labelling on there's not much room left for things like detailed instructions, hence the DVD and printed instructions........

Doing a 38 foot boat with two people was hard work. With hindsight, it would have been better to do the boat in quarters rather than halves, as that would have removed the race against the resin going off.....

On thing: we had a paint mixer to go into the power drill. That removed the effort of manually mixing the resin and made it easy to keep the copper in suspension.
 
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Wow, people here get very heated over these discussions.

Go to hell!

Seriously though folks, I think its important to remember that jonjo5 started this thread with the intention of passing on a few tips re Coppercoat application. Really no need to attempt to shoot him down in flames for what was intended as a help to others. Perhaps a bit of constructive criticism might have led to a more useful discussion.
 
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The label on the back is mostly H&S stuff plus what it can be used for. No further advice on its use. i would expect information about its use , as paint thinner for example , to be in the paint manufacturer's product data sheet.
Every major marine paint manufacturer disagrees with you, have you noticed the mini instruction booklet attached to the tin of International, Hempel and Blakes pots in a
chandlery? Why don't you write to them advising they are wasting their time trying to assist customers use their products successfully.
 
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Every major marine paint manufacturer disagrees with you, have you noticed the mini instruction booklet attached to the tin of International, Hempel and Blakes pots in a
chandlery? Why don't you write to them advising they are wasting their time trying to assist customers use their products successfully.

No mini instruction books on my tins of International thinners. Just loadsa H&S stuff in umpteen lanuages
 
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