[Harp-L] Reed Profile - More Questions



I went back to my copy of The Harp Handbook and found the photo of the reed lathe on page 10. The accompanying text reads:

"3) The reed profile is automatically milled into the edge of a rolled brass strip which is then cut into individual reeds - note that the lathe bears the name "Richter" (photo 1)."

Thank you, Steve, for an excellent book, and for the additional information about the milling process, repeated below. This is very important additional information about the reed-making process, and sheds considerable light on it.

Steve Baker:
"In order to understand reed profile, it helps to know how reeds are made. The profile is milled crosswise into the upper surface of the strip of brass from which the reeds are then cut lengthways, so the milling is at right angles to the length of the reed. The Harp Handbook contains photos of this process. This is necessary in order to create reeds with the same dimensions but of different pitch (e.g. 4-blow in a C and a G harp, both long slot mensur = same size, but different pitches) or vice versa ( e.g. 4-draw in a C, a long slot mensur, and 4-blow in a D, a short slot mensur, different sizes but the same pitch). Apart from this function, the profile influences response, opening reed behaviour (bending & overblows) and longevity."
That difference in mensurs certainly explains why two reeds of the same pitch but from different keys require additional work when cross-pollinating for repair by scavenging from another harp but not the same key. I had always assumed that two reeds of exactly the same pitch would be exactly the same (with the same mensurs). I now understand that in order to get an even response, the mensurs would have to be different for different keyed harps, even though the pitch and length of the two reeds is the same.
Monsieur Smokey-Joe posits a possible 3-step process for milling the reeds:
"Nothing..really. I think there are probably 40 'Raw' reed sizes. I think they would be made in a sheet and individual reeds sheared off and then go on to further milling. The further milling would produce 135 different 'rough' reeds. Further trimming of lengths and milling 
end weights would produce 450 'basic' reeds. Further thinning and tuning and we would then have 1500 'finished' reeds. Leaving only 'fine' tuning."
>From an industrial point of view, I find it hard to imagine that two additional milling steps would be applied to individual reeds. Given the tiny size of the individual reeds, I would think it would be cost-prohibitive to manipulate each reed so that it could be specifically milled. But then, I'm as ignorant as dirt about the actual process used. Perhaps I have misunderstood Smokey-Joe's process...perhaps he is referring to a 3-step process applied to the strips of brass PRIOR to stamping out the individual reeds (which would then have the appropriate mensurs). IIRC, Vern Smith's custom set of reed making machines were applied to individual reeds. My impression is that Vern did this to experiment with various individual reeds and materials, and not to attempt a commercial venture into reed making. It seems enormously time-consuming.
More questions, s'il vous plait (presuming this is NOT Hohner "proprietary and confidential" information; if so, please ignore; I don't want anyone violating intellectual property rights just to satisfy my curiosity):
(1) Are specific reed profiles (mensurs?) milled in one pass? (It would appear so from The Harp Handbook.) I assume that means one specific reed type (with specific mensurs) is lathed into one strip of brass at one time and then the individual reeds are stamped from that strip of brass. Dang! That seems like a lot of changes to lathe settings to produce a complete set of reeds! OR an enormous number (1500?!?) of lathes would have to exist in the factory. I guess when you're creating gazillions at a time, it doesn't seem like that much work. I'd certainly opt for a CNC machine with a program that could be changed on the fly.
(2) Are the weights (blobs) on the end of the lower pitched reeds milled as part of the mensurs milling process?
(3) Regardless of the process, is specific response (the flexibility of the reed, for lack of a better terminology) the reason for using a weight at the free end of the lower-pitched reed, rather than a more gradual taper (possibly requiring a much thinner reed)?
(4) Is manufacturing convenience the reason for milling across the reed (laterally) instead of milling along the length of the reed (longitudinally)? In my ignorance, I assume that might be one of the reasons for earlier reed fatigue. Or, because of the fine-grained milling process used, is that no issue at all? (Yes, I know: EVERYTHING in industrial engineering is a tradeoff of various factors. I much prefer reeds with average longevity at a reasonable [to ME] price vice reeds with optimal longevity at an exorbitant price.)
(5) Given that the milling process is applied to the upper side of the strip of brass, I assume that the lower side of the brass is completely flat. Is that so? That would answer my earlier question about various substitutes (like razor blades) as reeds.
Thank you all for participating in this discussion. Lest anyone wonder, I am NOT a machinist nor a mechanical engineer (that must be painfully obvious to those of you who are experts in those fields); I am a retired software engineer - and I intend to stay as retired as I can afford! I'm interested in the topic of harmonica (including reeds) design as a means to the end of making my own harmonicas play better for me. I have no intention of trying to compete with any commercial company. That said, I do wish Brad Harrison good luck in creating his business; he's going to need it to break into a long-established, VERY competitive and EXTREMELY exacting environment.
Regards,
Crazy Bob 
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