Coppercoating a metal hull?

[OndinePLC]

Coppercoat on a metal hull.

When I had a boatyard the golden rule for steel and aluminium boats was “Do not use copper based antifouling”.

This was to avoid electrolytic action between the copper paint and the steel hull. Normally we used TBT tin-based bottom paint.

Recently I saw a vintage steel-hulled boat for sale that has been treated with coppercoat. I looked up their website and they state that it is suitable for metal hulls (steel and aluminium) so long as they are first protected with a 500 micron ( half millimetre) layer of epoxy barrier coat to isolate the copper from the hull.

However I wonder about the effect of small holes or imperfections, or scratches, and also possible interaction between the sacrificial anodes on the hull and the exposed copper surface.

Does anyone have experience of coppercoating a metal boat? Would you recommend it?

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"A Small Slip" and "Desperate Deliveries"

True sailing adventures by Cris Robinson.
Paperbacks and e-books available at Amazon Kindle.

[sailorboy1]

Wouldn't scratch be through both the copper coat and the barrier coat? In order words it is now just bare metal (steel) and it isn't in contact with the copper coat.

But, wouldn't the real way to ask be to email/call Copper Coat?

[OndinePLC]

Well let's see.
I have advised Coppercoat of the post and look forward to seeing their comments.



-------------------------------------------------------------------------------


"A Small Slip" and "Desperate Deliveries"
True sailing adventures by Cris Robinson
Paperbacks and e-books available at Amazon Kindle.

[OndinePLC]

I received a prompt reply from Coppercoat, the gist of which is:



"Certainly you are very welcome to use Coppercoat on a steel boat, and this is something we have been doing for over 25 years. If you go to www coppercoatsuperyacht com and www coppercoat-commercial com you will see lots of examples of Coppercoat being used an a wide variety of metal craft as well as sub-sea installations.

But Coppercoat will not bond directly with bare metal surfaces, so these must be primed well with an appropriate two-pack epoxy resin beforehand. Popular options are Jotun Jotamastic, International Interprotect, Hempel High Protect II, etc."


However I would really like to see independent opinions from cruisers who have used Coppercoat on steel or aluminium hulls and seen how it performs over a period of years.


Of course if everybody has followed the Golden Rule there won't be any out there!




--------------------------------------------------------------------------


"A Small Slip" and "Desperate Deliveries"
True sailing adventures by Cris Robinson
Paperbacks and e-books available on Amazon Kindle.