These are my conclusions and thoughts on profiling as I think it is from what I gathered from the factory visit.
Another thing he said, which I forgot to mention: Probably to emphasize his role in the production process ;) (but he surely isn't wrong!). He said that every mistake done by him (because they translate to such big numbers) always create a huge amount of work for the other employees. I.e. if the reeds don't have the right size or if they are tuned wrong, every single harmonica in that batch has to be corrected tediously. So the actual cost of the harmonica very much depends on the accuracy of his work.
1:10 - 1:14 : scraping out the profile ('milling' is possibly the correct term) 1:15 - 1:22 : stamping out the reeds
1:54 - 1:58 : scraping out the profile/milling the profile 2:04 - 2:13 : stamping out the reeds
And to end here's a in many respects very interesting interview of Kinya Pollard with Rick Epping [Link].
This excerpt might give a clues on how the profiles should/could be altered to allow greater playability: " Rick: There really isn’t a fundamental design difference between the built profile, the current, or previous production reeds, and the reeds that are used for the XB40. It’s more subtle variations in it. There’s a kind of process that is used for Accordion reeds called Egalitarization (sic). The only usage I’ve come across in English translation is in England when speaking about equalizing soccer scores. It (sort of) means equalizing the responsive of the reeds. It is where the built profile is adjusted on the Accordion reeds so that the same amount of pressure, from the low to the high, is required to get the reed to respond. Normally on factory reeds, the amount of pressure needed to get that reed to respond is not entirely smooth, and, in general, increases as you go up. So at the highest reeds you need a little more pressure. This is kind of the way it is with harmonicas as well. This technique of working on the profile of the reed and adjusting is so that the response is more uniform. There is a more even gradient that is not so steep that gets stiffer as you go up. It is not so much a theoretical thing where you mathematically arrive at the optimal profile for every reed, but is something best, or usually, done by hand, by actually hand finishing the reeds. ‘Hand Finished Reeds’ are where you take a factory reed and you reprofile them and finish them by hand to get a good response out of it. Going by what I’ve learned from Accordions and early sample harmonicas, I was able to come up with reeds that really responded well—I studied their whole characteristics. Then I refinished factory reeds to similar kind of response profile, which I sent back to Germany. They were able to measure my samples on their machinery and come up with the program that would match the profiles, and produce machine-made samples. "
That's all I've got.
---------- germanharpist on YT. =;-) - Resonance is KEY!
Last Edited by on Jan 21, 2010 10:43 PM
After thinking about it for a while, this is all I can think of (i.e. the apparently obvious):
Re-profiling is simply making the higher reeds thinner. And you have to do it in such a way as not to weaken but (hopefully) streangthen the reed. And, of course, it mustn't change the pitch...
Now, the question still remains, how you would go forward doing it.
I have difficulty imagining just scraping on the surface (although this is the only method that I can think off) because of this article again from Kinya Pollard. [Link] " Alternate Curvature //**arching**// Method Two
- Repeat steps 1 through 4 from Curvature Method One
1. Being careful not to "bend" the reed, gently slide the .002 feeler gauge between the reed and the reed plate - pushing it back approximately 80% towards the rivet end.
2. Working from the back to the front of the reed, gently stroke the top full length of the reed with the edge of the Brass Flat Strip (.064 x ½" x 6"). This technique is similar to "curling" gift-wrapping ribbon with the edge of a pair of shears.
- Repeat steps 7 through 9 from Curvature Method One "
Although it would created the wished effect of reducing the thickness of the reed, and you could correct the created arch afterwards, it just creates way too much tension in the reed that it could be of any good, IMO (however, it could be that it's not the bad kind of tension...).
---------- germanharpist on YT. =;-) - Resonance is KEY!
Last Edited by on Jan 21, 2010 11:45 PM
good info. but im confused. the only way to make the reed thinner would be removing material. an by doing that you would be putting it out of tune. or flattening the reed would make it thinner but then it would get stuck in the reed slot. what am i missing? ----------
When the reed is stamped out, it becomes slightly curved across the width of the reed. Stroking the reed as written above,takes this curvature out by flattening the reed, making it last longer.
The slight curvature creates more stress on the reed causing it to fail sooner.
It also slightly widens the reed, making it more airtight in the slot.
It is only done on the thinnest part of the reeds, not on the"thick" parts on the lower note reeds.
