copper bottom paint on stainless steel

Hi all,
I painted the boat bottom with a paint that has a lot of copper in it. I screwed up an painted the props and rudder.http://www.trawlerforum.com/forums/images/trawler/smilies/sk/facepalm.gif Question; if I leave it on how fast will it corrode the steel? It is ablative paint. Do I risk it? Once the boat is in the water it will have light use for months, until restoration is complete.

Thanks

Gordon B said:

Hi all,
I painted the boat bottom with a paint that has a lot of copper in it. I screwed up an painted the props and rudder.http://www.trawlerforum.com/forums/images/trawler/smilies/sk/facepalm.gif Question; if I leave it on how fast will it corrode the steel? It is ablative paint. Do I risk it? Once the boat is in the water it will have light use for months, until restoration is complete.

Thanks

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Most bottom paints in use where I have my boat have a high copper content.

Everyone I know paints their rudders with it, and most have SS rudders. I certainly do. I haven't noticed any deterioration of my rudders in 22 years, so whatever effect it has is negligible.

I also paint my props with the same paint frequently. For a few years I was leaving one blade unpainted, just to see if it made any difference. It does, as unprotected, the barnacles are bigger and more densely attached. Those prop barnacles will effect performance more than any other factor, so paint those props. I haven't seen any deterioration in the bronze props either.

It is quite common to paint shafts and rudders and struts too. Also through hull and through hull grates. It will not hurt a thing!

Same as Keith, been painting our for over 20 years with bottom paint as well with no apparent side effects. Had the yard do the bottom this year as I was laid up with a bad knee and they painted the running gear and rudder with Petit Zinc Spray.

Stainless prop and rudder? Are you sure they aren't bronze? I think that would be more common, no?

twistedtree said:

Stainless prop and rudder? Are you sure they aren't bronze? I think that would be more common, no?

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Maybe, at least the prop for sure on our type boats. Our rudder is SS as is the rudder shoe but the prop is bronze. We paint everything and have never had any corrosion or electrolysis issues.

What they said. Plus: Bottom paint is of no use on metal unless isolated from the metal by a barrier coat or several coats of old, dead bottom paint. This directly from Pettit. After coating my rudder and skegbar with epoxy, the bottom paint works just like it does on the hull.

Thanks

Thanks everyone. Just made my life easier.