Copper-nickel alloy keeps hulls foul-free

Currently on show at the Daily Mail Ideal Home Show is a revolutionary concept in either residential or commercial applications of a floating building.

Currently on show at the Daily Mail Ideal Home Show (running until 4th April 2004) and situated in the "Waterside Living" feature is a revolutionary concept in either residential or commercial applications of a floating building, the Optimum 60 from Waterspace.

As a luxury dwelling, this unique concept of vessel is virtually a multi-purpose floating penthouse capable of being transported to any waterway or mooring basin.

Faced with the requirement to be relatively maintenance free, the manufacturer has turned to a novel technique to protect the underwater sections.

Any structure that is destined to spend all of its life submerged in water needs to be fit for purpose.

If the water is pure and free from animal, vegetable and mineral additives and contaminants, then manufacturers of working and pleasure vessels could happily specify a selection of modern materials.

The facts are, however, that both fresh- and salt-water environments are far from pure and have their own respective characteristics.

In fresh water such as canals, navigable rivers and reservoirs, algae and weed tend to become attached to the underside of vessels, particularly if they are relatively static in their applications.

In seawater environments many different varieties of micro-organisms exist which, together with molluscs, such as barnacles, form the familiar build-up of fouling.

This is observed at its extreme on the permanently submerged pillars of piers where often the original structure cannot be seen for the sheer volume of attached growth.

For owners of pleasure craft built in GRP, glass fibre being the popular, practical and economical material from which to construct strong hulls for vessels, the traditional protection against bio-fouling has been an annual application of specialised paints to freshly scrubbed hulls.

Regular re-application is necessary because these paints are designed to wear away when in contact with water, making the attachment of bio-fouling difficult to sustain.

Early versions contained materials toxic to marine life; however legislation in recent years has restricted the ingredients of such paints to less harmful compounds.

A more eco-friendly solution with minimal maintenance, eliminating the need for this annual lift-scrub-and-paint procedure, is now commercially available courtesy of an innovation from the company Ecosea.

Copper sheets were used centuries ago to "skin" some of the earliest wooden naval craft, protecting against bio-fouling and also attack by marine borers.

Ecosea has homed in on the exceptional and unique properties of one of its alloys, copper-nickel.

At a ratio of 90/10 this alloy displays the optimum resistance to bio-fouling in all water systems, requiring no replacement, usually for the life of the product it protects.

In most cases any routine inspection required can be readily performed without lifting.

In the case of glass-fibre hulls and other structures, a matrix of small platelets of the alloy are applied to the underwater areas as self-adhesive sheets approximately 300 x 360mm, each with enough flexibility to be shaped to the substrate, forming a comprehensive and continuous cladding.

Flatter areas can accept plain sheets of copper-nickel.

Any small gaps between the platelets and sheets are subsequently filled with a grouting epoxy, which is "squeegeed" over the fine joints and the excess simply wiped off.

Cuproguard is not only suitable for cladding to GRP, it can be used just as easily and effectively on wood, aluminium and steel, hulls and structures.

The performance of the 90/10 alloy as a protective cladding is well established as a result of many years of testing on both pleasure and commercial craft with an amazing success record.

Experiments on yachts, ferries, piers and static structures, have shown that bio-fouling control can be simple and effective using copper-nickel.

In some cases entire hulls have been constructed in the alloy.

The very thin, complex oxide skin that forms when the copper-nickel is submerged gently dissuades attachments in an ecologically compatible manner.

After long static exposure a light slime will form, itself containing bio-material.

Macro-fouling may occasionally try to colonise too, but will slide off readily, either with natural water movement, or alternatively with a light wipe to clear the surface.

Now, with the availability of the product from Ecosea, benefiting from the properties of copper-nickel can be simply achieved via a simple post operation to most new or existing hulls and underwater structures.

The illustration of the latest application for Cuproguard, as the product is branded, is the cladding of the wetted surfaces of the 48t, multipurpose floating building from the innovators of floating offices, dwelling-houses, shops or business headquarters, Waterspace.

Founded in 2002 by Nils Baker, Waterspace takes a leaf out of its own portfolio by operating from a floating office moored on the Thames at Cardogan Pier.

The company plans to use inland basins and waterways to launch a fleet of vessels typified by the illustration.

On the performance of Cuproguard Nils Baker comments: "If you consider for a moment that one of our vessels is perhaps being used as the high-tech centre for an international corporation, full of computer and delicate communication equipment, there is no way the owners would tolerate being lifted out of the water annually for a scrub and a recoat of anti-foul".

"It is simply impractical".

"The availability of the proven alternative, Cuproguard, is the perfect answer to the problem".

"It is an elegant solution, it is aesthetically acceptable, it makes economic sense and it works".

"You cannot ask more of a product than that".

"Furthermore it has a 'double-plus' in the case of the GRP used in the construction of our vessels".

"Even with the top quality materials chosen and the best manufacturing techniques used in construction, we have to remember that water is an aggressive environment".

"Osmosis - the ingress of moisture into fibre-glass structures causing them to swell and slowly degrade - is a major undesirable, but in very rare circumstances can occur".

With the hull completely encased in Cuproguard this potential hazard is eliminated".

"This makes the copper bottoms we fit doubly appealing".

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