Re: [Harp-L] Specification of and Sources for Harp Reed Materials

["Vern Smith" <jevern@xxxxxxx>]

Good spring materials make good reeds.

Mark's Handbook for Mechanical Engineers has a section that includes brass 
and bronze as well as steel and stainless steel spring materials. It gives 
the properties that affect the use as springs/reeds... modulus of 
elasticity, density, and strength.

Trade secrets of manufacturers are over-rated.  If anyone were really 
curious, a mass spectrometer analysis would give the percentages of each 
metal in any reed alloy.  Standard polish, etch, and microscope examination 
would reveal the amount of work hardening.

I have used shim stock obtained from http://www.mcmaster.com/  You want 
thickness of .012" brass/bronze or .014" SS  in the rolled or work hardened 
condition.  "Half-hard" is a typical spec for copper alloy material.

Reeds are very difficult to make.  I found it necessary to make special 
machines for the purpose.  The width, non-linear tapering thickness, length, 
and the location of the rivet/screw hole on the centerline all must be held 
to tolerances of  about +0.000 -0.0005"  You know from tuning how sensitive 
the pitch is to tiny changes in thickness.  If you are interested in making 
the machines for making reeds, email me off list and I can share my 
experience with you.

I once expected to use exotic reed materials to make exotic harmonica 
sounds.  I was disappointed.  I experimented with brass, bronze, 
beryllium-copper, spring steel, and stainless steel.  If the pitch and the 
stiffness/responsiveness of two reeds is the same, they will sound the same 
even if they are made of different  materials.  I can engage in a long 
discussion about why this is so but you wouldn't like it because it would 
sound a lot like the discussion about comb materials.  I think that the only 
benefit from using better materials might be resistance to fatigue. 
Beryllium copper might have better fatigue properties but it is brittle and 
easy to break while gapping.

Small differences in alloying materials don't have much effect on the metal 
properties that affect reed performance.  I am very skeptical of any claim 
that a "magic formula" will produce any meaningful improvement in 
copper-alloy reed performance.  There is no reason why the best alloy would 
not have been discovered and put to use long ago.

I applaud Seydel for bringing out a line of SS reed harps.  I think it 
likely that they are less subject to fatigue.    I love Seydel harps and the 
folks who make them but I think that they are on very thin ice in claiming a 
characteristic SS tone.

The cost of the materials is not a significant factor in making reeds.  The 
cost of machining them is.  SS is more costly than copper alloys because it 
is harder, tougher, and causes more tool wear.

Vern
Visit my harmonica website www.Hands-Free-Chromatic.7p.com

----- Original Message ----- 
From: "Robert Coble" <robertpcoble@xxxxxxxxxxx>
To: "Harp-L" <harp-l@xxxxxxxxxx>
Sent: Friday, October 03, 2008 9:35 AM
Subject: [Harp-L] Specification of and Sources for Harp Reed Materials



Is there any specification of harp reed materials (outside of the
trade secrets of each manufacturer)? If so, are there commercial
sources for the materials in limited (hobbyist) quantities?

Please DON'T suggest the current harp manufacturers. I am aware
that both Hohner and Seydel will provide individual reeds for a price.
I'm also aware that their prices are astronomically LOWER than the
cost of creating the tools to make my own reeds, and probably lower
than the mere cost of the material in the reeds because of the
economies of scale of a large manufacturer.

I'm still curious, even if I never make the first reed. Indulge me,
please. I know from the Harp-L archives that several people have made
their own replacement reeds from a variety of sources and materials.
I also know that Brad Harrison is gearing up to produce his own brand
of harmonicas based on his own unique reed design. How did he arrive
at his choice of reed materials?

(Let's talk about ANYTHING except comb materials!)

Thanks for any and all help!
Crazy (obviously) Bob
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