 The Clarinet BBoard
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Author: jeffreyc
Date: 2005-07-09 17:28
I'm curious if anyone on the list is successfully using a hardness tester to "qualify" cane before making them into reeds.
Note, I'm not talking about a simple dial indicator, but a dial indicator that has a function which applies a predetermined force and then measures displacement of the measurement tool after the force is applied.
In this usage, the higher the displacement the softer the cane.
I can find a good deal of research on oboe/bassoon usage on the web.
Apparently bassoon and oboe players often use this device successfully in an effort to not waste their time on making reeds out of cane which doesn't meet their basic criteria.
But there appears to be little information about the success of its use for clarinet reeds.
Thanks,
Jeffreyc
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Author: ClariBone
Date: 2005-07-09 18:23
Correct me if I am wrong, but are you referring to the "Perfecta Reed" or a similar device? This device is listed in the Accessories section to the right-------------------------------->
under the Reed Wizard. The seller, Ben Armato isn't it, can give you more info on the product and after conducting a search under "Perfecta Reed" I came up with a lot of threads that mentioned it. Check it out!! Hope this helps!!!
P.S. If I'm completely off base with what you're talking about, I'm sorry but your post seemed vague to me.
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Author: woodwind650
Date: 2005-07-09 20:59
claribone:
he's not talking about the perfecta reed. jeffreyc is talking about a device that measures the "density" of the cane and not the thickness; which is what the perfecta reed does.
double-reed players often use the density of the cane to determine whether or not their cane is viable to use.
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Author: BobD
Date: 2005-07-10 13:18
What the guy is looking for is not a hardness tester or a density tester....it would be called a stiffness tester....as far as I'm concerned. But, no, I'm not using one as I don't make reeds. I'm wondering if when did use such a tester if one would support both ends of a piece of cane and apply the load at the mid-length or clamp one end and apply the load at the other end.
Bob Draznik
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Author: jim S.
Date: 2005-07-10 15:23
There is such a device on the market, has been for years. Italian, I think, or at least has an Italian name, but appears in major U.S. catalogues at any rate. Have never heard anyone mention it as useful.
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Author: Arnoldstang
Date: 2005-07-10 15:44
The device might be a durometer. Steve Goodson...sax gourmet mentions this product. Bill Roscoe used to grade his cane 1-10 in hardness....he had his own methods of determining oboe reed hardness. . I think Arundo reeds used to sell different grades of hardness....I don't see it anymore on their webpage. John
Freelance woodwind performer
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Author: jeffreyc
Date: 2005-07-11 03:15
Yes, woodwind650 is correct.
This is capable of doing the same thing a perfectareed does (measuring thickness), but it is also capable of measuring the "hardness" of the cane.
It does so (in simplest terms) by taking a thickness measurement (x) before application of a predertimined force. You then turn a switch to apply the predetermined force and then take a thickness measurement again (y). Subtracting y from x tells you the amount of displacement. The more displacement, the "softer" the cane.
Devices like this are used on construction projects and in all sorts of machining for verification and quality assurance of the hardness of various substances.
I'm curious if anyone uses this device with clarinet reed cane with any success. Theory is that if the instrument is valuable for double reed players to qualify their cane, it might be for clarinet players as well.
Thanks,
jeffreyc
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Author: BobD
Date: 2005-07-11 11:22
"Devices like this are used on construction projects and in all sorts of machining for verification and quality assurance of the hardness of various substances."
I think you've hit the nail on the head.
Bob Draznik
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Author: Bob Phillips
Date: 2005-07-11 16:56
Stiffness testing of a material is not simple. The standard method is to bend the test specimen with a four point loading. Imagine a popsicle stick (test specimen) supported near its ends (two points of support) and pressed downward at two more points (for loading points). The downward-pressing points are equally distributed along the section of the test specimen between the lower points.
This loading puts a constant bending moment along the center of the test specimen. The load and the deflection due to that load are measured as the load is increased.
Now, the stiffness of the material in the test specimen can be calculated from the load/deflection data. That requires that the cross sectional shape and dimensions of the test specimen be known. As an example, if the cross section were rectangular, the material stiffness (Young's Modulus of Elasticity) would be computed from:
E = ( W*a ) / (Y * width * thickness * thickness *thickness ),
Where W is the force pressing down on the test specimen, a is the distance between the two upper loading points, and Y is the deflection.
Because the thickness enters the calculation three times, in the denominator, the results of the test are extremely sensitive to the machining accuracy and measurement of the test specimen.
In the case of a hunk of reed, the cross section is complicated to describe mathematically, and the sensitivity of the results to its dimensions will remain.
In a practical sense, the stiffness of the material is correlated to the material hardness, so a more practical screening test for reed material might be to use a hardness tester. In hardness testing, a precisely formed point is pressed into the material with a given load, and the amount of penetration is measured. Note, though, that hardness testing permenantly deforms the test specimen, and normal use does not.
An arbitraty interpretation of the amount of penetration is used to specify the material hardness.
I assume that the "bark" on the cane would not have the same hardness as the part of the reed that actually vibrates, so the hardness would need to be measured in the core material. Also, the material should be thick and wide compared to the indentation made by the tester so that the specimen geometry doesn't (so much) affect the measuremenjt.
I image that screening material with a hardness tester could give insight to cane quality, but wonder if experience with the stuff wouldn't serve as well.
Bob Phillips
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