[Harp-L] Reed "Profile"

[Robert Coble <robertpcoble@xxxxxxxxxxx>]

I've been systematically combing through the Harp-L archives. It's fascinating to find such a treasure trove of information on every possibility related to harmonicas!

While in the stacks (so to speak), I noticed a peculiarity regarding the term "reed profile." It appears that there are two quite different usages of this term. Perhaps I misunderstood, so if there is a different set of terms, please enlighten me.

One usage appears to refer to the curvature of the reed between the reed pad and the tip. The generally accepted wisdom is that the reed should sit flat (to the plane of the reedplate) between the reed pad and a point approximately 2/3 of the length of the reed without descending below the surface of the reedplate. The remaining distance should be arced upward (curved gently) to produce the appropriate reed gap at the tip.

An alternate usage appears to refer to the thickness of the reed along its length. It appears that there is a subtle (not necessarily visible to the naked eye) difference in thickness which is machined into the length of the reed. This subtlety supposedly is the driving factor behind the necessity for approximately 1500 individually different reeds required for a complete set of reeds for a complete set of harmonicas in all keys. Although there are reeds with the same lengths and set to the same pitch, apparently there are subtle differences so that performance and longevity are optimized.

That last usage brought to mind some questions.

Is there any known equation (published) defining the natural pitch of a reed, given a particular type of metal, length, and thickness profile? Given my past life in association with engineering, I believe it highly unlikely that specific reed thicknesses for over 1500 reeds would be arrived at through purely empirical means (trial-and-error). I realize that the descriptive equation most likely is some weird integral equation that only a calculus nut (or an engineer) is likely to be able to decipher and turn into a CNC milling program.

When a reed is machined, does the cut occur across the reed (perpendicular to the reed length) or along the reed (parallel to the reed length)?

I note that one of our greatest "MacGyver-like" resources, the great and wonderful Smo-Joe, has often experimented with various sources for reeds, such as razor blades of varying materials. CAVEAT: Smo-Joe STRONGLY recommends against wasting time and effort on transforming razor blades into reeds, given the amount of time it takes. (I don't know of any such restrictions from Smo-Joe on beating razor blades into plow shares.) Please don't mistake my feeble attempt at humor as being disparaging to Smo-Joe: I have nothing but the highest admiration for his inventiveness as both an experimenter on harmonicas and as a musician. I always look for his posts whenever I see them in the  Harp-L digest.

Given that a razor blade is angled from BOTH sides down to the edge, does one side of the razor blade have to be flattened, or does it work as-is with the "reed" becoming progressively thinner on BOTH sides from reed pad to the tip? If so, what (if anything) does that say about the effort to make EVERY reed unique in a harmonica?

May I have a description of the process and tools used to reform a razor blade into a reed? (This may be in the Harp-L archives already; since I'm only up to about May 1995 so far, I may not have read it yet. If in the archives, please just point me to the relevant post.)

I'd like to experiment with making a reed by hand. Actually, that's NOT true. I'd like to be able to purchase individual reeds of a particular material from someone else, but no one seems to be in that market at the present time. I'd love to do it as a charitable venture to the harmonica world, but alas, Uncle Sam seems to have the exclusive rights to creating money whenever desired. Those of us who are retired have to live within our means and only dream of unlimited wealth. (Hey Ma! Where's that winning lottery ticket?)
Regards,Crazy (Isn't it OBVIOUS?!) Bob 
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