Coppercoat on bronze/DZR Brass fittings

Dazedkipper

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Once again when I washed off at the end of the season the Coppercoat I'd applied at the start of the season to the skin fittings flaked off. Over the years I've tried it with an epoxy primer and directly onto the metal with the same result, it's becoming tedious. Am I doing something wrong or is there a special way to prepare the metal? I noticed an Oyster that had new Coppercoat at Foxes but the skin fittings were uncoated, no one was around to ask unfortunately.
 

Tranona

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No real need to coat them - as you have discovered it does not stay on. However I used to mask mine off and spray them with Hemplel Ecopower as used on the saildrive housing and propeller blades. You could also try Velox.
 

Birdseye

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Once again when I washed off at the end of the season the Coppercoat I'd applied at the start of the season to the skin fittings flaked off. Over the years I've tried it with an epoxy primer and directly onto the metal with the same result, it's becoming tedious. Am I doing something wrong or is there a special way to prepare the metal? I noticed an Oyster that had new Coppercoat at Foxes but the skin fittings were uncoated, no one was around to ask unfortunately.
getting paint, whether epoxy or not, to stick to non ferrous isnt easy. What often happens is that a bare edge or hole through the coating to bare metal allows corrosion to start and this travels under the paint at the interface between paint and metal . Almost a parallel to how oxides form where stainless fittings are screwed into ally. If you can get a full impervious surface coating that adheres well, then you have a chance. But with skin fittings, by definition, a part will always be bare metal.

In my experience the worst by some distance is lead as in keels. You stand a chance if you take a flapper disk to the metal to get it shiny and clean them, immediately epoxy coat and then with coppercoat or antifoul on top but then all it takes is a mild grounding or bad coating where the keel was chocked to start the rot.
 

dansaskip

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Similar to Tranona I just put on some "normal" antifoul paint to mine, apply with a brush takes minutes. Why sweat over little problems.
 

Dazedkipper

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Once again Hammerite Special metals primer comes up trumps. It adheres very well to copper alloys and Coppercoat adheres to it after light abrasion.
That's interesting. I used it on a propeller once u der Trilux but because it's water soluble it simply dissolved. I assume that when overcoated with Coppercoat it's completely sealed but what about the hole in the skin fitting, doesn't detachment start from there as another reply suggests?
 

vyv_cox

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That's interesting. I used it on a propeller once u der Trilux but because it's water soluble it simply dissolved. I assume that when overcoated with Coppercoat it's completely sealed but what about the hole in the skin fitting, doesn't detachment start from there as another reply suggests?
It is water based but not soluble once dry. I have had the same coat of primer on my prop for 10 years! I only abrade off the Velox and leave the primer alone.
 

Tradewinds

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It is water based but not soluble once dry. I have had the same coat of primer on my prop for 10 years! I only abrade off the Velox and leave the primer alone.
How do you do that without removing the primer as well? This time I used H-SMP and Velox like yourself. The velox has flaked off the SMP in quite a few places. I didn't have this problem with the Velox metal primer. I used SMP this time because I found the Velox topcoat tended to soften the velox primer when brushed. I'll probably end up removing the lot and start from scratch again - it will probably be quicker in the long run. A shame as the SMP has really stuck to the prop. It's a pity it has no anti-fouling properties!

Perhaps I should have keyed the SMP before applying the Velox?
 

vyv_cox

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How do you do that without removing the primer as well? This time I used H-SMP and Velox like yourself. The velox has flaked off the SMP in quite a few places. I didn't have this problem with the Velox metal primer. I used SMP this time because I found the Velox topcoat tended to soften the velox primer when brushed. I'll probably end up removing the lot and start from scratch again - it will probably be quicker in the long run. A shame as the SMP has really stuck to the prop. It's a pity it has no anti-fouling properties!

Perhaps I should have keyed the SMP before applying the Velox?
I only abrade lightly and the primer remains in situ. I originally abraded the primer with 180 grit, to which the Velox has adhered well. I only used HSMP originally because I had a full pot but subsequently read of various problems with Velox' own.
 

superheat6k

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My boat was hauled out yesterday to reveal hardly any wear to the antifoul applied just before I bought her 2 years ago, although that said my usage has been too light for other reasons.

The props are fully coated with what looks like the same antifoul as the hull and it is very well attached. The barnacles have mostly been removed with the jet wash then a scraper, but the tubular worms remain.

I intend to use Velox as I bought several cans a few years ago when they announced it was being discontinued.

So do I ...

1 Remove the lot from the sterngear with a wire cup brush on the grinder then start afresh
2 Remove just the worm using HCL with wallpaper paste - and if so will this damage the paint anyway ?

Then for the primer ...

Is the currently available Hammerite Special Metals Primer stil a decent formulation as a base for Velox ?

Can I simply apply the Hammerite on top of the sound prior coat of AF ?

Do I need to if the old AF is hard and sound ?

I used to be able to answer much of the above from y own experiences, but its been a while since I used a traditional AF, and for the main hull I'm paying the yard to apply the stuff - getting too old for that now !!!
 

vyv_cox

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There is no point applying Hammerite over other paint, it is an etch primer intended to lightly corrode metals. I would abrade all the old paint off, then prime.

You could apply the Velox over the existing paint but without knowing what it is I think there is a good chance it will be unsuccessful.
 

superheat6k

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Thanks. As a bonus I have found a 6 year old can of primer 3/4 full, plus a 1/4 tin of white and full tin of black Velox plus.

Also found two anodes not worn at all (obviously connection problems) so will sort the circuits and saved ~ £70 on the necessary anodes.
 

Greg2

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I haven’t anti-fouled props and shafts before but suffered notable fouling last year so having read about HSMP and Velox on here, that is what I have applied for this season. I didn’t abrade the primer once dry though so we will see how that works out.

I intended to strip the previously anti-fouled P-brackets and rudders back to bare metal and do the same but whatever was on them under the self-polishing stuff I had applied the extremely well adhered and was proving difficult to shift, even with fairly extreme power tools, so I decided to apply a coat of International Primocon before applying Velox. A bit of an experiment😉
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