Re: [Harp-L] Reed "Profile"





On Jun 16, 2009, at 10:34 AM, Robert Coble wrote:


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!

Actually, I have a lot more than is in the archives...(as he ducks the shoes). Seriously though, in the past there have been books. Most of which didn't cover the fine points of harmonica. These were written by professionals who, and here's where I'm going to take a chance, didn't divulge the REALLY fine points. The points that separate the champs from the chumps. My belief, and this is only my opinion is that the pros were protecting their own rice bowl, while, at the same time, were at least giving an inkling as to what the harmonica is all about.


Why a 'few'guys wrote the books is beyond me as it has been my experience that most of the old masters died and took their knowledge with them. The first book I read was by the great Blackie (Alan Schackner). I found t to be a great book, but it was geared to the new player and unfortunately, I was already set in my ways and it didn't show me anything I didn't already know. The second book, which was loaned to me by a lady friend of my wife's, was by the great Tommy Morgan. IT, also, was old news. Now I don't mean any of this in a BAD way. It's just that, I was already too lousy a player to change. Btw, I was unaware, at the time, that this Morgan was the guy that I had heard countless times during my entire LIFE, on so many movies and commercials, that I could never count.

By the time the Doug Tate book came along, I was already too cheap to spend money if only to see if there was anything in there that I wasn't aware of. It turned out to be the best book of the bunch.

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.

I could be way off base here but I always thought of the word profile as being a side view. I seem to remember that from mechanical drawing class. So, I guess that ANY side view qualifies. Even a personal profile is a side view...of a person.

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,

No, you cut that off.


or does it work as-is with the "reed" becoming progressively thinner on BOTH sides from reed pad to the tip?

No, you are up INTO the reed. See, you will need a rivet pad attached to your reed. So, you have to take about 1/16" (1.5mm for our European shut in friends) off of the one side. THAT removes the sharp honed edge. The best way to cut the pad is to shape it like 'home plate'...with the stem of the reed coming off of the end that usually would have a point. . In other words, NO inside corners. Since I was always working with cuticle cutters and scissors, I didn't want the chance of a 'rip' by allowing an inside corner. Inside corners require a 'double snip' and are too risky in these small sizes that we are working with. I always cut larger than needed and finished with files/abraders/emory.


If so, what (if anything) does that say about the effort to make EVERY reed unique in a harmonica?

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 'finish' reeds. Leaving only 'fine' tuning.

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.)

Monseur 'either Dave Payne or no gain' has one of my 24 year old spl-20s that has a razor blade reed in it. The harp is beat up but it plays ok. I used it Buckeye to play 'After the Lovin'. Which is on you-tube. f I werent such an idiot, I could take photos and send them out with this Apple. It can do everything. The trick is that the person on this end can't be a scarecrow.

I'd like to experiment with making a reed by hand. Actually, that's NOT true.

The springiest material I have found are contact points from onside electrical relay switches. They have enough alloy in them to be quite springy. Springy is what you want. Springy is what you need. Common brass is lousy to work with. You can cold hammer it. heat treat it, anneal it, and that sometimes helps. But do yourself a favor. Use a real reed. They're easy to scavenge. When I was young I had no respect for harps and when I thought they sounded off, I would toss them off a bridge into the river. Then, for a while, I hung onto 'some' of my my reed plates. About 5 years ago, I sent G a 7 lb cigar box of parts and harps.


Now that I can afford it again, I play em and then throw them away.

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.

People should be able to fix their own harps. If you don't learn to fix your own, it could cost you a small fortune to PLAY harp. Especially chromos.


Smokey Joe


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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