Re: [Amel Yacht Owners] Coppercoat revisited
Andrew & Kate Lamb
I pinged this post across to Coppercoat for comment (I have always found them very responsive to advice both before and during the application process) – this was the response.
“My first point would be that most Coppercoat is applied directly to bare gel-coat. For most boats, especially those made of GRP (such as Amel yachts), no primer is necessary. Coppercoat bonds perfectly and permanently with appropriately cleaned and abraded gel-coat, so pre-treating with a primer is unnecessary.
However, for those people that do want to apply some epoxy primer beforehand, there are some basic rules to follow. These rules are common sense and not unique to Coppercoat.
In the simplest terms, there are two general types of protective epoxy primer on the marine market, (a) solvent-based and (b) solvent-free. Both are good but have different characteristics when applying and (more importantly for this discussion) when over-coating.
Solvent-based epoxies are physically thinner and easier to apply. But by virtue of being heavily solvented, they need to be allowed to fully cure before “sealing” them with another epoxy, such as Coppercoat. For most of the commonly used systems (such as International Gelshield 200, Hempels Light Primer, Awlgrip Hullguard ER, and so on) this full cure normally takes about 7 days (depending on temperature). As these solvent-based epoxies normally cure to a matt surface, they usually require no further preparation before over coating with Coppercoat. However, to be really safe, it is of course sensible to lightly abrade the surface to be sure of a good physical key.
It is true that if you over-coat a solvent-based epoxy with another epoxy, before the solvent-based system has been allowed to cure, the second epoxy can trap in the remains of the solvent, and this can lead to micro blistering later down the line. Of course, anybody that reads the instructions provided with all coatings schemes, and indeed any reputable boat-yard, would already know this.
If a professional boat-yard applies Coppercoat (or any other such epoxy coating for that matter) over an uncured surface of solvent-based epoxy primer, they are not following standard guidelines and potentially would be liable for any repairs subsequently proved necessary.
The rules for using solvent-free epoxies are different. Solvent-free epoxies are normally thicker and more difficult to apply, but therefore take fewer coats to achieve the required thickness. One of the advantages of using solvent-free systems (such as West System epoxy or International Gelshield Plus) means that normally you can apply Coppercoat whilst the solvent-free epoxy is still curing and just slightly tacky to the touch. As there is no solvent to worry about, you do not need to wait a week or so, which shortens the time needed to treat the boat. By applying the Coppercoat to the solvent-free epoxy while it is still just tacky and not quite cured, a strong chemical bond can form.
If this over-coating window is missed and the solvent-free epoxy is allowed to fully cure it will give a hard and glossy finish. To over-coat such a surface (with Coppercoat or any other coating), it must be thoroughly abraded so that a good physical key is provided.
In conclusion, Coppercoat can (and is) applied successfully to boats with no epoxy primer, to boats with solvent-based epoxy primer, and to boats with solvent-free epoxy primer. All that matters is that you follow the guidelines appropriate for the boat/products in question.
I am delighted to say that we are fast growing to the stage whereby 10,000 boats per year will be treated with Coppercoat. And while this is good news for the owners, the environment, and for us as a business, it does mean that there are up to 10,000 opportunities each year for people to make mistakes with their applications. Of course, we try very hard to avoid these by providing written instructions, an application demonstration video, and constant telephone and email support. But unfortunately not everyone follows this advice and occasionally mistakes (such as using primers incorrectly) do occur. Dealing with such cases is just part and parcel of what we have to do.”
From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: 9 March 2016 16:10
Subject: Re: [Amel Yacht Owners] Coppercoat revisited
Well, that's a first ! not heard of any other supplier who has had that problem. Nor we, now in our sixth year. It's not perfect, but for us it has saved us endless sandings , fillings and paintings, to say nothing of hauling charges. There are many recorded instances of people using it happily in all waters for ten years and more.
I guess that, as with all paint jobs, fail to prepare and prepare to fail.
There are at least 50,000 boats worldwide, including many commercial ( oil service vessels etc,) and multimillion dollar yachts who use Coppercoat. If you google Coppercoat you can read of issues that people have raised, but actually extraordinarily few.
Up with the Coppercoaters!
Ian and Judy, Pen Azen, SM 302 Preveza Greece
amelyachtowners@... <amelyachtowners@...> on behalf of 'Bill & Judy Rouse'
yahoogroups@... [amelyachtowners] <amelyachtowners@...>
As some of you know I am prejudiced against Coppercoat because of the experiences of others that I know and what I have seen. I am also prejudiced against Coppercoat and any other product that makes claims of endurance 2-4 times the normal range.
I received this from a Canadian Professor (Chemistry PhD) and active cruiser to the Med, Caribbean, Pacific, Indian, South Africa, and North America:
"There was a discussion about Coppercoat some time ago and I said that
we had it for 3 years and were happy with it. Well, I just want to
post an update:
We've noticed bubbles on our Coppercoat. There were a few, but then
regularly more and more started appearing all over the place. We were
sure that it was because of unprofessional application of Coppercoat
back in South Africa.
We've just hauled out at a yard who used to be a Coppercoat supplier.
It turns out that our issue with bubbles is not unique, but rather a
byproduct of Coppercoat design. They said that the issue is with the
primer being solvent-based and Coppercoat being water-based. If
Coppercoat is applied even on slightly not-cured epoxy primer, then
the primer will off gas resulting in bubbles. On the other hand if
Coppercoat is applied to the dry primer it won't be able to adhere
well resulting in larger areas falling off. That's why this yard
stopped distributing and applying Coppercoat.
So now we're up to redoing the bottom paint including epoxy primer
frown emoticon. There is a quite new large Catana next to us that also
had to strip falling off Coppercoat. An expensive lesson in chemistry,
I thought that you Coppercoat believers should know and be aware of this.
Rodney Bay Marina for a week