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Discussion Starter #1
Anybody ever try this?
You could prime the bronze prop or maybe one coat of pure epoxy, then the copper loaded epoxy.

You can get copper powder on ebay pretty cheap.
groundhog
 

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Telstar 28
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Don't put copper anti-fouling on a BRONZE prop. It will dezincify the prop and make it worthless... :)
 

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It sounds from your plan to coat the prop first with epoxy that you are aware of the theory regarding mixed metals.

Making an emulsion of epoxy and copper powder, as you describe, will more than likely do noting except coat the prop with epoxy. The copper would be bound up in the epoxy making it effectively inert. You could put TBT in the epoxy with the same intent and it would similarly do no good.

One suggestion - Pettit Zinc Coat Barnacle Barrier paint
 

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Actually, fine copper powder mixed into epoxy makes a fairly decent anti-fouling layer... provided you use enough copper powder per volume of epoxy.

It sounds from your plan to coat the prop first with epoxy that you are aware of the theory regarding mixed metals.

Making an emulsion of epoxy and copper powder, as you describe, will more than likely do noting except coat the prop with epoxy. The copper would be bound up in the epoxy making it effectively inert. You could put TBT in the epoxy with the same intent and it would similarly do no good.

One suggestion - Pettit Zinc Coat Barnacle Barrier paint
 

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Actually, fine copper powder mixed into epoxy makes a fairly decent anti-fouling layer... provided you use enough copper powder per volume of epoxy.

I'd be interested in seeing any reference indicating this is true as standard epoxy is not soluble in or permeable to water making the hypothesis dubious at best. Same principle as typical barrier coat
 

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At best, you'd be making your own "copperpoxy" type product, and there's a lot of debate over how well that works. AFAIK even the companies that make these products say they are not for use on props though--that should be a hint.
 

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Discussion Starter #7
Well, I work with a silver epoxy product that is so loaded with silver, that it is highly conductive.

It get's weaker as a glue though, as metal content is increased.

The thing would be to have enough CU in soulution to do the antifouling, but still be strong enough to stay on the prop when rotating.
 

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I'd recommend you look at CopperCoat, which is a UK-based antifouling paint that is just that.... very fine powdered copper in an epoxy base.
I'd be interested in seeing any reference indicating this is true as standard epoxy is not soluble in or permeable to water making the hypothesis dubious at best. Same principle as typical barrier coat
 

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I'd recommend you look at CopperCoat, which is a UK-based antifouling paint that is just that.... very fine powdered copper in an epoxy base.
Somehow, I don't think that copper-loaded epoxies (CopperCoat, Copperpoxy etc.) are as easy to duplicate as simply dumping some powdered copper into a tub of West System.

And FWIW, in my neck of the woods, copper-loaded epoxies (which are not paints, BTW) don't work for sh*t.
 

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I'd be interested in seeing any reference indicating this is true as standard epoxy is not soluble in or permeable to water making the hypothesis dubious at best. Same principle as typical barrier coat

Epoxy with enough of any filler is and can become permeable. This is why wood flour or Microballoons are not generally recommended fillers for below waterline applications.

I just had my bottom stripped faired and barrier coated. When we had it down to bare gelcoat I noticed microballoons around the strut used as a filler/fairing compound.

When I put my meter on it it read nearly 6 times the moisture content of the surrounding polyester gelcoat (and no this was not Bondo it was epoxy & microballoons). We went ahead and removed all the microballoon filling and fairing done by the PO and re-did it with an epoxy mix consisting of milled fiber and cabosil.

The filler can contrubute a lot to moisture absorbtion despite it being mixed in with epoxy..

As others have said it is not a wise idea to coat a prop with copper as many of them are made from manganese bronze. Manganse bronze, depending upon grade, can have as much as 40% zinc content..
 

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However, I'd point out that this does not make the epoxy a non-standard epoxy.
 

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However, I'd point out that this does not make the epoxy a non-standard epoxy.
You should understand that the term"epoxy" is a generic one encompassing a wide range of epoxy resins. Also, the paint you referenced contains far more than just epoxy and copper powder which makes the copper:
1. bioavailable, and
2. semi-permeable (to water).
Simply mixing copper and a generic epoxy together is equivalent to magic dust. I don't know how else to simplify it.

Mainesail's description may be accurate but predicated on conductivity created by moisture of the entrained water in cavities.
 

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Just curious, but what do you base your statements on. What else is in their product? AFAIK, the paint is just what they claim it is... an epoxy with a filler made of a fine copper powder.

You should understand that the term"epoxy" is a generic one encompassing a wide range of epoxy resins. Also, the paint you referenced contains far more than just epoxy and copper powder which makes the copper:
1. bioavailable, and
2. semi-permeable (to water).
Simply mixing copper and a generic epoxy together is equivalent to magic dust. I don't know how else to simplify it.

Mainesail's description may be accurate but predicated on conductivity created by moisture of the entrained water in cavities.
 

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Mainesail's description may be accurate but predicated on conductivity created by moisture of the entrained water in cavities.
You don't need cavities only enough filler. Microballoons absorb moisture just as wood flour does. If you have a fairing filler of peanut butter consistency you have flour touching flour or balloons touching balloons which can wick moisture through the mix. There were no visible cavities in this microballoon fairing mix and it was a good mixture just not an appropriate filler for below water. If the fairing had been over coated with straight epoxy or even a slightly thickened epoxy mixture (not microballoons or wood flour) moisture never could have reached the balloons to begin the wetting out and wicking process. The more filler you mix into epoxy the more likely it will be for the filler to absorb moisture, if it is water permeable filler. The epoxy does not absorb moisture it is the filler that absorbs it and when thick enough you get wicking from balloon to balloon until it hits a 100% epoxy encapsulated balloon then it stops. The odds of water hitting a 100% epoxy encapsulated balloon get slimmer as the filler gets thicker.
 

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Avoid Coppercoat like swine flu...

Hi all.....
Found this thread as I was online today. My advice...be very careful with spending your hard-earned bucks on antifouling products claiming all sorts of miracles scenarios. I purchased and applied Coppercoat on my vessel a year ago. I was fastidious about preparation of the substrate and the coating application, and the coating began to craze and do weird things within 6 weeks of being back in the water. It has obviously had a serious incompatibility with my vessels epoxy treatment - applied 10 years prior, however the sales muppits from CC didn't enlighten me to any potential incompatibility issues, and were particularly unhelpful once I alerted them to my problem. You can read about my personal experience at the following link: Crap Anti-Fouling 'Coppercoat' - Do not believe the hype!! Avoid this 'product'. (RDBYC.com)

I DO believe that some folks have had a reasonable experience with this product, but that has been limited to new hulls without previous antifouling. My experience has been particularly galling considering the amount of research, effort & considerable expense that went into the hull prep and paint system.....and moreso once the morons at CC refused to offer any solutions, advice, or compensation.
My advice...avoid CC like a dose of swine flu.....:hothead
 

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Just curious as to what your previous epoxy coating was? It sounds like the previous epoxy coating was more the problem than the CopperCoat itself. I've spoken to quite a few people about CopperCoat and went with it after talking to over a dozen people, either via e-mail or by phone, including two friends who have between them over 22 years with the product currently on their two boats.

I had the previous anti-fouling on my boat removed via sodablasting down to the gelcoat, and barrier coated the hulls prior to applying the CopperCoat, and have had NO problems since doing so. I'm currently on my third season with it.

BTW, this doesn't look like crazing. It looks like bad prep. Did you tell them specifically what "epoxy" coating was previously applied to your boat.



Hi all.....
Found this thread as I was online today. My advice...be very careful with spending your hard-earned bucks on antifouling products claiming all sorts of miracles scenarios. I purchased and applied Coppercoat on my vessel a year ago. I was fastidious about preparation of the substrate and the coating application, and the coating began to craze and do weird things within 6 weeks of being back in the water. It has obviously had a serious incompatibility with my vessels epoxy treatment - applied 10 years prior, however the sales muppits from CC didn't enlighten me to any potential incompatibility issues, and were particularly unhelpful once I alerted them to my problem. You can read about my personal experience at the following link: Crap Anti-Fouling 'Coppercoat' - Do not believe the hype!! Avoid this 'product'. (RDBYC.com)

I DO believe that some folks have had a reasonable experience with this product, but that has been limited to new hulls without previous antifouling. My experience has been particularly galling considering the amount of research, effort & considerable expense that went into the hull prep and paint system.....and moreso once the morons at CC refused to offer any solutions, advice, or compensation.
My advice...avoid CC like a dose of swine flu.....:hothead
 

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It does remind me of a baked apple. That is, the top coating has wrinkled as it shrank and pulled itself apart, leaving the cracks showing. Look at their edges, it would appear just like they'd been pulled apart as the coating shrank, and failed to adhere to the material under it. (Could be an adhesion problem, could be the shrinkage was a thermal problem from cure rates?)
 

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If you have a fairing filler of peanut butter consistency you have flour touching flour or balloons touching balloons which can wick moisture through the mix.
Whoa, wait a minute, I was planning on using wood flour filler when doing my cored deck repair. Does this mean that it's a potential way for water to migrate back down into the deck? I should get a different filler then yes ?
 

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As others have said it is not a wise idea to coat a prop with copper as many of them are made from manganese bronze. Manganse bronze, depending upon grade, can have as much as 40% zinc content..

Hey Maine,

If you use an underwater primer it seems to me that then a copper based paint can be applied. I've done that for 20 years on my Max Prop. Knock on wood. I use interlux primewash, then primocon and then the bottom paint and it's good to go for about 3 years between haul outs here on the Cheaspeake. Note that Max Prop does not recommend using the bottom paint so caution is advised.
 

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Hey Maine,

If you use an underwater primer it seems to me that then a copper based paint can be applied. I've done that for 20 years on my Max Prop. Knock on wood. I use interlux primewash, then primocon and then the bottom paint and it's good to go for about 3 years between haul outs here on the Cheaspeake. Note that Max Prop does not recommend using the bottom paint so caution is advised.
I believe that the MaxProps were a more recent invention that didn't exist 20 years ago?
 
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