Coppercoat on propeller

AntarcticPilot

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As promised, but rather than simply posting the article here I have added it to my website. Copper plating a propeller

The boat was sold last year, so I cannot update further.
That looks very promising. Would the thickness of copper compromise the operation of a folding propeller? I have a Gori two-blade propeller. I presume you could expect the copper on the interlocking teeth at the base of the blade to wear rapidly, but this is also the area where fouling would be least likely to adhere.
 

vyv_cox

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That looks very promising. Would the thickness of copper compromise the operation of a folding propeller? I have a Gori two-blade propeller. I presume you could expect the copper on the interlocking teeth at the base of the blade to wear rapidly, but this is also the area where fouling would be least likely to adhere.
I do not know the thickness of the coating on my prop but the thickest coating specified by ASTM B734 is minimum 25 microns. I cannot see this having much effect on the action of a folding prop.
 

Poey50

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I do not know the thickness of the coating on my prop but the thickest coating specified by ASTM B734 is minimum 25 microns. I cannot see this having much effect on the action of a folding prop.

Vyv, I'd be interested in using this on my stainless steel Darglow Featherstream blades. Is copper close enough in the galvanic series not to be a problem?
 
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vyv_cox

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Vyv, I'd be interested in using this on my stainless steel Darglow Featherstream blades. Is copper close enough in the galvanic series not to be a problem?
My concern would be the adhesion of copper plate on stainless steel. I suspect that platers would want a nickel layer first, which introduces a further corrosion factor.
 

Poey50

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My concern would be the adhesion of copper plate on stainless steel. I suspect that platers would want a nickel layer first, which introduces a further corrosion factor.

OK thanks. I'd better stick to the usual dissapointing potions in that case.
 

lancsjohn

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I am restoring a 9M catalac which as twin steel rudder blades and an trying an experiment having sanding the blades to remove old paint they still have pitted corrosion so I paint one good coat of black hammerite smooth paint let it dry for several days then applied a second coat and immediately piled copper powder on the surface of the wet paint and brushed it allover with dry paint brush the copper powder dried into the paint immediately and the surplus powder brushed off easily at £23 /Kg it is worth saving so the rudder plate was over a plastic sheet supported on 2 blocks so the edges could be painted and coated.
The painted plate was covered in copper was immediately dry enough to handle and was turned over to treat the other side. The plate now as a copper powder surface which does not rub off by handling so I am hoping to launch next spring and see if it proves successful. As anyone tried this before?
 

vyv_cox

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I am restoring a 9M catalac which as twin steel rudder blades and an trying an experiment having sanding the blades to remove old paint they still have pitted corrosion so I paint one good coat of black hammerite smooth paint let it dry for several days then applied a second coat and immediately piled copper powder on the surface of the wet paint and brushed it allover with dry paint brush the copper powder dried into the paint immediately and the surplus powder brushed off easily at £23 /Kg it is worth saving so the rudder plate was over a plastic sheet supported on 2 blocks so the edges could be painted and coated.
The painted plate was covered in copper was immediately dry enough to handle and was turned over to treat the other side. The plate now as a copper powder surface which does not rub off by handling so I am hoping to launch next spring and see if it proves successful. As anyone tried this before?
An interesting idea! My concern would be whether the paint has sufficient adhesion to retain the copper particles once water is flowing by. Will be pleased to hear the outcome.
 

Neeves

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I forgot to say the two plates used about 600grms of the copper powder over an total area of approx 12 sq feet.

Agree with Vyv - Interesting.

What copper powder did you use? Copper powder comes as flake (for printing and paint) or as more spherical (I think for powder metallurgy). Flake primarily comes from Eckart or Schlenk.

Jonathan
 

Porthandbuoy

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Found this on t'interweb. Looks interesting, copper plate your propeller and then spray it with a mixture of bleach and seawater. How long will such a coating last though?

Patents Assigned to Propeller Antifouling Pty Ltd.
  • Prevention of marine encrustation on bronze propellers
    Patent number:
    6521114
    Abstract: From the time that they are immersed into a marine environment, bronze propellers are prone to attack by marine organisms, such as barnacles, coral and algae, which attach themselves to the bronze metallic surface, creating lumps on the propeller, which adversely affect its balance and cause impedance and vibration of the propeller and its boat in the water. Anti-fouling paints are either too toxic for the marine environment or lack smoothness on the surface. These problems have been overcome by polishing the propeller to prepare it for electroplating, cleansing to remove dirt and grease, electroplating with copper, followed by spraying with a standard solution (5%) of sodium hypochlorite and sodium chloride and allowing sufficient time for a reaction of the hypochlorite solution with the copper to form a firmly adhering conversion coating of basic cupric chloride. The coating is blue-green in color.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: February 18, 2003
    Assignee: Propeller Antifouling Pty Ltd.
    Inventor: Ronald Kempin

PS. A much longer description of the process here.
 
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vyv_cox

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Found this on t'interweb. Looks interesting, copper plate your propeller and then spray it with a mixture of bleach and seawater. How long will such a coating last though?

Patents Assigned to Propeller Antifouling Pty Ltd.
  • Prevention of marine encrustation on bronze propellers
    Patent number:
    6521114
    Abstract: From the time that they are immersed into a marine environment, bronze propellers are prone to attack by marine organisms, such as barnacles, coral and algae, which attach themselves to the bronze metallic surface, creating lumps on the propeller, which adversely affect its balance and cause impedance and vibration of the propeller and its boat in the water. Anti-fouling paints are either too toxic for the marine environment or lack smoothness on the surface. These problems have been overcome by polishing the propeller to prepare it for electroplating, cleansing to remove dirt and grease, electroplating with copper, followed by spraying with a standard solution (5%) of sodium hypochlorite and sodium chloride and allowing sufficient time for a reaction of the hypochlorite solution with the copper to form a firmly adhering conversion coating of basic cupric chloride. The coating is blue-green in color.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: February 18, 2003
    Assignee: Propeller Antifouling Pty Ltd.
    Inventor: Ronald Kempin

PS. A much longer description of the process here.
The spraying with hypochlorite accelerates the natural process, producing the oxy-chloride compound that is the antifouling agent. Copper plating definitely works, see my earlier post.
 

Porthandbuoy

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The spraying with hypochlorite accelerates the natural process, producing the oxy-chloride compound that is the antifouling agent. Copper plating definitely works, see my earlier post.

That was my understanding too. I've been following your posts regarding copper plating for years. I've even experimented with DIY copper plating using the 'paint on' method; with patchy results. It is very difficult for an amateur to get components clean, down to a granular level, without the use of acid baths. Still, having just bought a motorsailer, I'm seriously looking at getting the prop professionally stripped, prepped and plated.
 
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