[CR]Copper-plated frames

(Example: Framebuilding:Norris Lockley)

Date: Mon, 7 Apr 2008 03:58:19 -0700 (PDT)
From: "Norris Lockley" <norris.lockley@yahoo.com>
To: classicrendezvous@bikelist.org
Subject: [CR]Copper-plated frames

In reply to Peter Schwars query about such frames I might be able to offer a little help, having, in the early 80s made a few Show machines finished with this technique, as well as others with brass or nickel or black chrome plating.

As has already been pointed out not all copper-plated frames, ie Wiliers, are plated, but merely sprayed up with a copper flam translucent paint, this coat being applied over a polished chrome plate..the whole finish being topped off with a durable, one hopes, varnish coat..or two.

A finish that is truly copper-plated will have had a layer of pure copper applied to an initial layer of chromium by the electro-plating process. This is of course the reverse of the normal chrome-plating process whereby the copper is applied first and then the finish layer of chromium, although the better quality processes will have a layer of nickel between the copper and the chromium. In some cases, I believe, the copper will be applied directly to the polished steel of the tube, without the chrome initial layer.

A true copper-plated finish will then be topped off with varnish coats to prevent the copper from oxydising/tarnishing. The real problem with this finish is to make the varnish stick to the copper. At points or spots where the varnish peels off the copper will turn dull green.

If the frame has only had the copper -lacquer - over - chrome treatment, the exposed copper paint is unlikely to go green, but is more likely to peel or chip off the chromium base coat completely, leaving an apparently copper-plated frame with silver patches.

If the frame had been copper-plated the layer should be several microns thick and it should be possible to polish the metal with any one of dozens of proprietary polishes, but as in all such metal-finishing tasks, care should be exercised and some experimentation carried out delicately beforehand. After cleaning the polished area should be re-varnished. Normally if the plating process has been carried out to a high standard, the copper should adhere keenly to the steel tubing of the frame.. or to the chrome base layer.Peeling of copper off steel is not common.

The last copper-plated frame that I built was for my mechanic as a leaving presnt when he went off to Paris to ride for the Peugeot-sponsored ACBB top amateur team. In early February he had to report to a training camp on the French Riviera.. So complete with resplendent copper frame on the pro-bike rack on the boot of his car he drove all the way from Calais to Nice. Unfortunately en route he encountered the worst of inclement weather, to which the copper plate was exposed for many hours. Unfortunately, the sprayre who had applied tro lacquer coat to the shining copper had not done too good a job, with the result that the frame arrived at its destination sporting copper-plated tubes riddled with dozens of greenish spots, where the lacquer had failed to provide adequate protection from the elements.

Electro-plated finishes are only as good, generally speaking, as the varnish or lacquer coats that area applied as the final barrier to the elements and to wear-and-tear.

This account of the finish is as related to me by the companies that undertook the work for me..they were the experts not myself, and I can appreciate that techniques and processes will vary from country to country, industry to industry.

Norris Lockley Settle UK

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