 The Clarinet BBoard
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Author: Philip Caron
Date: 2020-04-09 05:52
My Bb R13 was made around the late 60's. A couple years ago it got probably its first full overhaul. Leaks were fixed, keywork was improved, etc.
The work revealed a problem with the key for throat G#. The original key was a little short, and the pad barely reached the hole to cover it - the outside edge of the hole was very near the outside edge of the pad. This was the source of a kind of phantom leak - under pressure, or with a fatiguing spring, it sometimes leaked.
My repair person said this was not terribly out of the ordinary; he'd seen similar things from Buffet before. They have been known for sometimes marginal key work.
He first tried crafting a slightly off-center pad to better cover the hole, but wasn't satisfied with the result. After discussion, he bent the key so that it reached further over the hole. After that it closed with the pad better centered, and also with improved mechanical advantage so the closing force was greater. It seemed to work.
However, in the ensuing year I started squeaking rather often, especially, but not only, in harder left-hand passages. The repair person and I both checked for leaks without finding any. I figured my technique was just going to pot, so I started focusing on that, particularly left hand technique. Among other things I finally started daily practice from a good scale book. The frequency of squeaks went well down, but not completely away.
Self-teaching I've been slow to zoom in on specific causes. The most frequent cause of squeaking is my left index finger brushing that throat G# key enough to slightly raise the pad. Asking myself why, I wonder if lengthening the arch, which had the effect of slightly lowering the key on the hole side of the pivot, didn't also slightly raise the actuator on the other side of the pivot. I might be brushing it more because it's higher off the clarinet. While playing, my finger feels it much of the time.
Maybe, maybe not; by eyeball it's hard to tell. I'm reluctant to alter my current hand and finger position (though I am experimenting with just that) because apart from this problem my technique is coming along pretty well. What I think I'd like is to lower just the actuator side of that key a little bit, while maintaining it's travel distance on either side of the pivot.
Maybe this work could be arranged, though no doubt the repair person is social distancing. I'm leery of trying to bend just that part of the key myself; I might have to reduce the height of the contact post beneath the actuator by some "right" amount as well. Maybe I could, ah, just file down the top of the actuator a little, somehow retaining the basic contact shape and all the other operational aspects of the key. How hard could that be?
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Author: Tony F
Date: 2020-04-09 06:29
I experienced exactly the problem you describe on an R13 that I had some years ago, and I've also had it on Boosey and Hawkes instruments. B & H are renowned for their fat keys, so my fix on that one was to reshape the key by slimming it slightly. On the R13 the key shape was OK, so I bent the key slightly so as to lower the actuating lever. I reduced the thickness of the cork on the underside of the key to compensate. As a small bonus, by doing this I slightly reduced the venting of the G#, which improved its tuning. The key bending was done with two pairs of pliers to avoid stressing the instrument.
Tony F.
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Author: Bob Bernardo
Date: 2020-04-09 06:51
God advice from Tony. It shoudn't be too hard of a fix.
Designer of - Vintage 1940 Cicero Mouthpieces and the La Vecchia mouthpieces
Yamaha Artist 2015
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Author: clarnibass
Date: 2020-04-09 10:04
If you are rubbing it closer to the end of the touchpiece then it can be very easy to bend it lower (it would bend close to where it is brazed to the hinge, so move lower near the end).
As Tony mentioned, sand the bumper or put thinner material to compensate for the reduced travel. Especially easy if is one of those clarinets where the G# uses a very thick bumper against the body, but should be possible either way probably.
>> the outside edge of the hole was very near the outside edge of the pad <<
With a stepped pad or not? If not, a stepped pad can be used to its advantage in cases like these.
If it's still a bit short (borderline), the angle part of the key cup arm can be "flattened" to some degree. Maybe that's what they have already done. Some other adjustment might nee to be made to compensate for that.
If the above doesn't completely solve the issue, then a permanent solution is to re-braze the key to the correct length. Either by the more often used method of cutting the arm and adding some length, or by removing the key cup and re-brazing it farther. Both methods have advantages and disadvantages and cost can depend on how much you care about the way it looks (plating, etc.).
Of course the touchpiece can be shaped to fit better if that will help, and assuming you will need to mill/grind/file the outside of it, also depends how much you care about the way it looks since it would remove the plating at least.
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