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Satin/pearl chrome question

2005

I am in a similar situation the questioner who posed question number #1751.

I have recently acquired a Velocette motor cycle dating from 1937. The machine is very original condition and quite a bit of the original "satin/milky pearl chrome" survives. It is not cadmium or nickel plate. I would like to restore the plating using a process as close to the original one as possible.

Now Velocette was always a family run concern and always had a reputation for producing a high quality, well engineered product. The same process for plating parts such as kick start and bolts was still being used on motorcycles still being produced in the 1960's. I would guess they were simply using the same plating vendor throughout this period.

Knowing their reputation for quality and based on the long term survival of the original plating I suspect that this process was developed to achieve long life but reduced cost with respect to regular decorative chrome. I am hypothesizing they used this finish to avoid cost in some way but in no way impact durability.

I now very little about plating processes but one guess would be that this process was maybe used to avoid the need for costly polishing preparation. (a shiny finish tends to show up blemishes while the satin/milky pearl process would not)

In your response to #1751, you said chrome could be done directly on copper. Would this produce the finish and durability that was achieved with the original 68 year old plating?

Again pardon my ignorance but I did read something on another site that indicated that a "milky looking deposit" was as a result of using "too low a current plating density"

The only other clue I can give you is that when the plating deteriorates it appears to chip off and not rust through with pin pricks.

If I could determine how it was done my plan is to attempt persuade my friendly local plater to try it. I have seen this question asked many times in various forums but have never seen a definitive answer to exactly how it was done.

John Ellis
hobby - Pleasanton, California, USA

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2005

Modern chrome plating is bright and reflective because the underlying nickel is bright and reflective. In 1937 the processes for producing bright nickel were pretty much in infancy, so much nickel was plated in the unbrightened condition, and then chrome plated, or it was buffed bright and then chrome plated. I'm guessing here, but from what I know of the history of the British plating industry and British bikes, I will hazard the guess that the original nickel plated was deposited in the dull or, at best, semi-bright condition and then chrome plated, giving a "satin" finish. Plating for a smallish manufacturer like Velocette was basically a cottage industry (they may have done their own), and was not very sophisticated. What they lacked in reflective brightness they made up for in thickness so some of this old plating has proven very durable.

No plating is done by those seventy year old methods today, but a plating shop which specializes in restoration plating can probably duplicate in appearance what you have if you have at least one piece in good enough condition for them to see what needs to be done. Look in Hemmings Motor News for such platers.

Good luck restoring your Velo. As they say, we need to save every one of them as there will never be any more.

Jeffrey Holmes, '59 Sprite, '63 Norton Electra

Jeffrey Holmes, CEF
Spartanburg, South Carolina

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2005

Thanks Jeffrey

I will check out Hemmings Motor News. In the late 1960's I owned a 1963 Norton Navigator. It was in very nice condition, and after 1960 Triumph 21 it felt really peppy. It had only done 10k miles when the main bearings went. I remember I phoned the factory service to ask what was going on. I spoke to this "old/experienced" guy who told me that all these models suffered from condensation in the crankcase. He advised me to use marine oil. Never did and it was still running ok when I sold it (45 pounds I think). I replaced it with a 1964 Velo Venom, which I still have and restored last year. The 1937 KSS which I just purchased was the subject of my enquiry.

John Ellis
- Pleasanton, California, USA

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You're welcome. I expect you'll find a plater who can do what you want, but if not, let me know. We can't give commercial endorsements on this site, but if you need help later, I may be able to put you with a sympatico plater.

Nice bike. Even better when ridden.

Jeffrey Holmes, CEF
Spartanburg, South Carolina
2005