Copper-Plating Propellers

[sailalfin]

Does anyone has had some experience in the subject of copper plating propellers? Would like to discuss this.

[delmarrey]

Why would you want to copper plate something that is already resistant to corrosion. It'll start to flake once it's use up.
If you want to keep the sea life off then use Marine Propeller Nano Coatings - Nanotechnology
or Propspeed USA or..............................

[hellosailor]

"Why would you want to copper plate something that is already resistant to corrosion."
You've never had to dive on the prop with tools and implements of destruction to clear barnacles off it?! Leave a nice clean bronze folding prop unused for 3-4 weeks in the wrong waters (even the NE US) and it can become useless. Bronze just isn't good enough.

Unused for 3-4 weeks? Yeah, well, sometimes, not often, the unforgivable happens. :-)

[sandy daugherty]

Three reasons not to do that;
Copper plating will create galvanic corrosion, and disappear almost as fast as your zincs, with some of your precious bronze.
Copper isn't much better that bronze at deterring marine growth. (Bronze is mostly copper)
and I believe pure copper is not on the EPA's she-loves-me list.

The jury is still out on effective anti-fouling treatments for propellers, beyond keeping it polished mirror bright and running it every week.

There are a thousand unscientific approaches, each with it own highly opinionated hand maiden! If you listen carefully, you can hear them cracking their knuckles in preparation to setting me straight once and for all!

[Bash]

Originally Posted by sandy daugherty

Three reasons not to do that;
Copper plating will create galvanic corrosion, and disappear almost as fast as your zincs, with some of your precious bronze.
Copper isn't much better that bronze at deterring marine growth. (Bronze is mostly copper)
and I believe pure copper is not on the EPA's she-loves-me list.

To that you could add a fourth reason: copper is a relatively soft metal.

[S/V Illusion]

why not simply spray on a couple of coats of Petit Zinc Coat barrier paint on the prop which is exactly what it is intended for - to minimize growth. I know many folks who's experience mirrors mine that it is a very effective relatively cheap and long-lasting product.

[Hudson Force]

I'm often close to the Luddite plan with my prop only coming out of the water once every three years or so. It seems that while underway, we change our environment enough to prevent the growth of varieties of orgnisms that have very specific tolerance levels. This might not be true of the pelagic cruisers, but coastal cruisers are moving to different salinities and the terretories of predators that feed on those that cling to our boats. There is often a different community of organisms that can be found at locations just thirty miles apart. I do find that I sometimes need to clean my prop and rudder in the spring or summer after staying at one location for a few weeks and I do this with snorkeling gear, and a synthetic abrasive pad and a thin flexible putty knife only when I'm preparing to cruise again. This usually means I perform this task about three times a year. We all choose our battles,- I'm ready for the ocassional swim. Take care and joy, Aythya crew

[beachhowes]

A friend of mine who kept his boat at Port Canaveral tried copper plating on his prop with poor results. My uncoated prop fouls in 2 weeks or less. I'd love to find something that would last a year.

[foggysail]

YES!!! I had my props plated about 4 years ago and NO, THERE IS NO GALVANIC CORROSION ON THEM. I have had mixed results though on performance most likely because I had them plated with just copper instead of copper nickel which would have given better results.

I encourage vertigris by washing them each year with hydrochloric acid. This also helps remove whatever growth that accumulated over the season. The plating shop I took them to was not happy about doing them, I doubt they would respond to a request to do them over with copper nickel.

Over all, the growth is not as bad as it was prior to the plating. I might have some pictures of them just after haul out but they are at home. They don't look pretty but never the less, the total build up is much less than before plating.

What inspired me was that Lord Nelson won the Battle of Trafalgar with the help of copper plating on his ships that minimized marine growth.

Foggy

[Astrid]

According to the US Patent office entry United States Patent 6521114

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.

Another patent, WIPO Patent Application WO/1998/007897

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. Ant-fouling paints are either too toxic for the marine environment of lack smoothness on the surface. These problems have been overcome by a combination of known steps, namely, polishing the propeller to prepare it for electroplating, cleansing to remove all traces of dirt and grease, electroplating with copper to a depth of at least 0.005' or 0.15 mm, followed by spraying with a standard solution (5 %) of sodium hypochlorite and sodium chloride in a suitable container to form a firmly adhering conversion coating of basic cupric chloride and then sealing for at least twenty-four hours. The preferred procedure for polishing is 60# grit size at 3500 sfm for roughing, followed by 180# grit size at 5500 sfm for finishing using grease as a polishing aid. Electroplating with copper to the minimum depth provides a smoothing effect ranging from 70 to 90 per cent. The container in which the hypochlorite spraying is carried out is preferably kept sealed until just before fitting and launching. A life expectancy of five (5) years can be anticipated with minimal maintenance every time the vessel is slipped.

Inventors:
Kempin, Ronald (3 Rodgers Place, Bull Creek, W.A. 6149, AU)

[delmarrey]

I just use a SS prop. The critters just pop off with a plastic ice scraper.

Wouldn't it be nice to get props coated with the plastic non-stick that is used in frying pans & pots. The only problem, once it gets scratched it'll start to peel with the spinning of the prop.

[Astrid]

something like teflon?

[James S]

Originally Posted by Astrid

something like teflon?

Yeah...why not?
I wonder what that process would involve?

[foggysail]

Originally Posted by Astrid

According to the US Patent office entry United States Patent 6521114

THANKS ASTRID!!!

Heck, I don't even know what those chemicals mentioned in your post are but I will check on them. The props are already plated so the next process should be easier........remains to be seen of course.

Foggy

[Astrid]

Sodium Chloride is the chemical name for salt (NaCl), while sodium hypochlorite is bleach (NaOCl). One can probably get the NaOCl in cyrstalline salt form, as used with treating swimming pool water, but I would not use household bleach as that also contains caustic lye and other chemicals that may retard the oxidation process