Leica MP Construction Material

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<p>The Silver MP top plate is clearly of brass. My question is whether the chrome finish is applied directly to the brass or is there a layer of nickel applied to the brass first, then the chrome applied to the nickel.</p>

[mukul_dube]

<p>The traditional method was to put nickel on the brass and chrome on the nickel -- and the MP was explicitly declared to look back to tradition. I assume there was a reason for the intermediate layer of nickel. Perhaps a metallurgist can say if that reason no longer exists.</p>

[GlennS]

<p> A quick search ..... http://www.finishing.com/faqs/chrome.html<br>

"Decorative chrome plating is sometimes called nickel-chrome plating because it always involves electroplating nickel onto the object before plating the chrome (it sometimes also involves electroplating copper onto the object before the nickel, too). The nickel plating provides the smoothness, much of the corrosion resistance, and most of the reflectivity. The chrome plating is exceptionally thin, measured in millionths of an inch rather than in thousandths.<br>

When you look at a decorative chrome plated surface, such as a chrome plated wheel or truck bumper, most of what you are seeing is actually the effects of the nickel plating. The chrome adds a bluish cast (compared to the somewhat yellowish cast of nickel), protects the nickel against tarnish, minimizes scratching, and symbiotically contributes to corrosion resistance. But the point is, without the brilliant leveled nickel undercoating, you would not have a reflective, decorative surface."</p>

[rossb]

<p>That's good to know. I have wondered about the finish myself. How about the black finish. How is that process done?</p>

[GlennS]

<p>Ross, there's a podcast about black chrome on the page I linked to above. http://www.finishing.com/podcast/willie_world.mp3</p>

[wendell_kelly]

<p>When plating over steel or other iron alloys, it is common to first apply a thin layer of copper to promote adhesion of the subsequent nickel layer, and then finally apply the top layer (usually also thin) of chromium.<br>

Presumably, the copper layer would not be needed over brass.</p>

[rossb]

<p> Thanks Glenn, I am saving my pennies for an M6 and was curious as to the finish.</p>

[Rob F.]

<p>Ross, the M6 top plate is zinc, not brass. I used to have an M4-P, with the black chrome partially worn off near the strap lugs. I recall there was a silvery layer where the black chrome was rubbed. So it could be that the silvery layer was nickel; I don't know. However, after this discussion about the base material being brass, I thought it might be useful to point out that it isn't brass for the M6, just FYI.</p>

[rossb]

<p> Are some of the Leica's an enamel finish or are they all a silver or black chome finish?</p>

[Rob F.]

<p>Some Leicas are factory painted. Some examples of Leica models produced in both chrome and original black paint include the M2; M3; the MP (both the original MP and the current one). Leitz referred to the paint as "lacquer" in the serial number listings supplied for inclusion in various books, such as the Hove collector's guide. Some Leicas have been produced in grey paint. Those include some wartime IIIc's, and of course the Hammertone finish M6. There have also been some Leicas in green paint, for the military, as well as a green SLR--I think it was a "safari" R4.</p>

[httpphoto.netsharedco]

<p>I do believe that all Leicas that were/are painted by Leica have top and bottom plates of brass without any applied nickel coating. The paint is applied directly to the brass.</p>