Copper Coat Maintenance?

[Alistairr]

We’ve just Boat our first yacht which is out of the water at the moment and has a copper coated bottom. We are told this is in good condition and just needs a rub down before re-launch.

Question is, what do we rub it down with as I was thinking a light rub, but I’ve been told it should be a hard rub. Does it need to be a light/good rub by hand or a light/good rub with electric sander.
What grade of paper should I use.

Propeller is antifouled, and been advised to sand it all off and leave it bear, is this good practise?
Bought is located at Ardfern on West Coast of Scotland.

Tia
Alistairr.

 

[Tranona]

CC should not need anything doing to it unless it is several years old. You can get some background and instructions on signs that it might benefit from a sanding from coppercoat - it is also on their website. Normally it just needs a pressure wash once a year.

Antifouling props is generally a good thing, although it is often difficult to get it to stay on. I use Trilux spray after cleaning back with a chemical cleaner, then primer and 3 or 4 top coats. Usually just needs a clean and a further couple of coats each year. others have success with a product called Velox, but I stay with Trilux as it is also used on the saildrive housing.

Fouling on props is even more variable than hulls and bare metal can stay clean one year and attract growth the next, so best to coat it.

 

[macd]

Rules of thumb: unless a boat's regularly parked in an environment where the Coppercoat doesn't activate fully (like many mud berths), there's no routine need for scrubbing. If the surface is green (dark green through to a quite vibrant mid-green, the latter usually nearer the waterline), it's active. If brown or black, it isn't.

Typically, active Coppercoat just needs a good pressure wash after coming out of the water. 'Refreshing' by abrading is not the norm: check out the Coppercoat website.

If it does need scrubbing, a large (green) Scotchbright pad is sufficient.

Do not leave your propeller bear. It could become quite grizzly.
Bare is OK, perhaps polished if you can be bothered.
(More seriously, some people do antifoul their props, but often find that nothing will stay stuck to them. There are various past threads on what works and what doesn't* We don't bother.)

* I see Tranona helpfully stepped in whilst I was typing.

 

[Ian_Edwards]

Hi,

I keep my boat at Loch Linnhe during the summer, not too far from Ardfern.

I found that CopperCoat need a light scrub with a green Scotch Bright pad every year, if I don't I get a good crop of barnacle on the bottom and a light green slime nearer the water line.

As for the prop', I tried antifouling it with different products for many years, none that successful, I now polish it and that keeps it clean for the 6 or 7 month she's in the water and is much less hassle to do messing around with multiple coats of antifouling paint, although I doubt a polished prop' would stay clean for more than one season.

 

[biscuit]

+ 1 for green scotchbrite pads, used lightly. see Coppercoat website.
I keep my copper coated boat just up the coast from Ardfern. Fouling is very light, barnacles are a minor problem.

 

[Neeves]

As mentioned antifouling props is the subject of a number of threads.

Velox has some good reports - try a search of YBW for 'Velox'.

One of the secrets, well hardly a secret, is to use the boat regularly - the longer the yacht stands idle the greater the chance of growth. Once growth starts you are on a very steep, slippery slope.

Jonathan

 

[AntarcticPilot]

Didn't Vyv_cox have some success copper-plating a propellor? Given that metallic copper is the original antifouling (at least, the first that actually worked!), and that Coppercoat works by exposing metallic copper in a controlled manner, it would make sense that copperplating a propellor would work. However, I can see problems with folding or feathering props.

 

[Tranona]

However, I can see problems with folding or feathering props.

I have been using Trilux on my folding prop successfully for 5 years. However, can't see that copper plating (at least on the blades) would cause any difficulties. They are after all just chunks of yellow metal just like a fixed prop. Hubs for saildrives might be more difficult as they have rubber bushes, although FlexoFold have solved that problem with their nes hubs that are composite.

 

[AntarcticPilot]

I have been using Trilux on my folding prop successfully for 5 years. However, can't see that copper plating (at least on the blades) would cause any difficulties. They are after all just chunks of yellow metal just like a fixed prop. Hubs for saildrives might be more difficult as they have rubber bushes, although FlexoFold have solved that problem with their nes hubs that are composite.

I was concerned that plating on the mechanism might reduce clearances, and even if it didn't impede the mechanism, would wear quickly. After all, you'd need a reasonable thickness of coating for it to last long enough to be worth doing. If it could be restricted to the blade and hub, it would be OK.

 

[Quandary]

I have been using Trilux on my folding prop successfully for 5 years. However, can't see that copper plating (at least on the blades) would cause any difficulties. They are after all just chunks of yellow metal just like a fixed prop. Hubs for saildrives might be more difficult as they have rubber bushes, although FlexoFold have solved that problem with their nes hubs that are composite.

I purchased a Flexofold folder from Darglow a few weeks back ( excellent service, always willing to discuss and explain specification issues) I also had a direct quote from Denmark, very similar price but they also offered the composite hub option ( bit more expensive than bronze) Darglow said that they did not wish to offer the composite hub 'just yet' implying that they wanted to wait to see how it worked out first. I was not disappointed by that, I feel that it is usually better to let the more adventurous (and wealthy) do the field testing on innovations. In my career in construction we had a policy of not using innovative techniques or miracle materials until they had been well tested by others, saved our clients quite a lot of bother and expense on several occasions.
On the 'how to finish it' question, I favour polishing particularly for folders where there are surfaces you can not paint. How well that works is a condition of frequency of use, if you always sail on and off your mooring it may not be the answer.

 

[Tranona]

The 2 blade prop is very simple with just the geared ends to the blades. I spray the whole lot with the blades in place and inevitably some gets on the gears but never any problem with either operation or fouling. Last summer I stripped the blades back in brick cleaner, abraded, primed and top coat. Boat came out last week and no fouling at all plus blades swung freely. Have to say this is one of the best bits of kit I have ever put on a boat.

 

[CJ13]

If the copper coat below the water line is greenish, then it’s oxidised & doesn’t need rubbing down. If it’s reddish then a light rub with a wet scourer does the trick.

 

[Hydrozoan]

If the copper coat below the water line is greenish, then it’s oxidised & doesn’t need rubbing down. If it’s reddish then a light rub with a wet scourer does the trick.

If I had Coppercoat, I’d be looking out for the green colour too; but it is not the result of oxidation alone.

The copper’s just being oxidised would produce red cuprous oxide (Cu2O) or black cupric oxide (CuO). Indeed, the Coppercoat site refers to the former being the ‘...highly effective antifouling agent [which] deters growth until the surface degrades further to become cupric hydrochloride. This final copper form is highly unstable, and is washed away by the movement of the yacht ...’. (http://coppercoat.com/coppercoat-info/antifoul-how-it-works/)

The green substance is probably the basic cupric chloride Cu2(OH)3Cl * and is I think what Coppercoat means by ‘cupric hydrochloride’ (though it’s not the most clear, modern chemical name for it). As it is the most thermodynamically stable solid corrosion product of copper in normal seawater, I presume the reference to ‘highly unstable’ is to its physical instability.

* The green might alternatively be the basic cupric carbonate Cu2(OH)2CO3 – the ‘verdigris’ of copper roofing and bronze statuary. Seawater’s pH and its carbonate and chloride concentrations put it close to the phase boundary between the two solids; the carbonate would be more likely to form at lower salinities.

 

[Halo]

If find Immersing your flex o fold prop in warm brick acid solution will restore it to a polished finish in about 2 minutes. It's hydrochloric acid and dissolves the calcium deposits

 

[Tranona]

If find Immersing your flex o fold prop in warm brick acid solution will restore it to a polished finish in about 2 minutes. It's hydrochloric acid and dissolves the calcium deposits

See post#11

 

[dave_gibsea]

Agree the copper coat doesn't need abrading but its important that any organic material not washed off by the high pressure wash is removed. I use a pot scourer for this, occasionally 400 grade wet n ' dry if that doesn't do the trick.

 

[Alistairr]

Thanks all for the replies, the copper is green in colour so I’ll do what suggest and give a very light rub down with a Scotch Bright pad.
The Prop is heavily coated in anti-Foul, so will rub that off and try and leave it polished.

Thanks
Al.