Re: [Harp-L] brass or bronze ?

[Vern <jevern@xxxxxxx>]

There are no hard-and-fast rules, but mostly...............

Brass, bronze, german silver, and beryllium copper are alloys of copper.  
Brass contains zinc as the principal alloying element, up to about 20%.
Bronze contains tin as the principal alloying element, up to about 10%.
Beryllium copper contains beryllium as the principal alloying element, up to about 2%.
German silver is an alloy of copper with enough nickel and zinc to color it silver.  It contains no silver.
Nickel is used as a plating.  It is relatively cheap and corrosion resistant. Some people are allergic to it.
Chromium is used as a plating. It is more expensive, shinier, very corrosion-resistant, very hard, and non-allergenic.  
During WWII, Hohner used aluminum in some reedplates.
Aluminum is used in some metal combs.  It must be anodized or powder-coated to protect it from corrosion.
Stainless steel is an alloy of mostly iron with additions of nickel, chromium and small amounts of other metals.  There are many types having substantially different properties.
Silver and gold appear as plating in expensive harps such as the Renaissance.  

Yellow reeds can be either brass or bronze.
Silver-colored reeds, as in some Seydel harps, are stainless steel.  
Red (copper-colored) reeds can be beryllium copper, rarely used nowadays because it is brittle.
Yellow reedplates are brass.
Silver colored reedplates are nickel-plated brass (Hohner) or german silver (some Seydels). 
Covers can be plated brass, plated steel (in old harps), or stainless steel.
Chromatic slides and their mating plates are mostly plated brass.
Chromatic mouthpieces are mostly plated brass.

Brass is easy to form and to machine.  Most parts of yellow metal are brass.
Brass can be very soft when annealed and hardened by cold-rolling, also called work-hardening.
Stainless steel is more difficult to form and machine.

Because so little of the metal is used, the cost of the metal itself is not a major factor.
However, its effect on the forming, machining, and plating processes is.

Vern








On Jun 16, 2010, at 4:43 PM, Doug wrote:

> I just realized that I am not actually clear on which parts of a harmonica are brass and which are bronze, if any.
> 
> So, on a CX12 for example, what is the material used for each of the reedplate, reeds, and slide??
> 
> Thanks in advance!
> 
> Doug H