 The Clarinet BBoard
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Author: Rusty
Date: 2009-04-05 23:13
If I take the mouthpiece off the top half of the clarinet. Block the end, I can draw a very good vacuum. If I repeat the process on the bottom half (less the bell) and making sure all holes are closed the vacuum is not very good.
I can`t find a leak anywhere and pushing on the closed pad holes does`nt improve the vacuum.
My request is, could you helpfull clarinetests out there see if the vacuum you can draw on both halves of your clarinet is the same good vacuum, or is the bottom half never as good as the top one? Thanks.
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Author: jparrette
Date: 2009-04-05 23:37
Hi Rusty,
If you can't get a suction on the lower joint, than you most definitely have one or more leaks. The bottom should seal as well as the top.
Secondly, the vacuum test is fundamentally flawed because you can suck ANYTHING shut. Since air is blown into the horn, a pressure test is much more accurate and informative.
Instead of sucking air out, seal the end of each joint with a plug (or your hand), cover the holes and blow into the joint. If you have a good seal, you should be able to use your tongue to seal the air in, and have the joint retain some air pressure. There are machines made to gauge the pressure that a joint will retain, but are impractically expensive for non-repair techs.
Good luck! :^)
John
John Parrette
CLARION MUSICAL SERVICES
john@clarionmusical.com
914-805-3388
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Author: Arnoldstang
Date: 2009-04-06 01:02
My clarinet seals as good or better on the lower joint. I for one believe the suction test is not flawed totally. There is some correlation between suction that lasts a long time and how well the clarinet is sealing. Albeit we don't suck when we play but the test is still an indicator. I don't find you can suck anything shut. If it is leaking badly you don't get a seal. The real indicator is how long it retains suction. If you get 30 seconds then things are working very, very well. Of course one should use the same finger pressure as when you play the clarinet.
Freelance woodwind performer
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Author: Rusty
Date: 2009-04-06 08:05
Don`t know. Normal creamy yellow ones. But I found the leak it is the lowest pad , one next to bell. Tech. repaired it 4hrs. ago but no diff. to the suction test. I wrapped plumber`s teflon around it and this produced the vacuum.
I doubt tho` whether it makes any difference if this pad leaks or not so close to the open bell.
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Author: Gordon (NZ)
Date: 2009-04-06 13:08
Possible leak sources include:
Porous membrane covering a pad.
Small splits across a tone hole edge.
Other imperfections of a tone hole edge.
Tone holes under ring keys are often inserts, glued in, and sometimes the glue job is poor, allowing air to leak.
Sometimes a drilling for a post or mounting screw has gone a little too deep, and into the bore.
Occasionally the timber itself has some blemish, eg what resembles a minute borer hole through it.
Somtimes the leaks are through splits in a tenon.
Post Edited (2009-04-06 13:23)
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Author: William
Date: 2009-04-06 15:01
"Since air is blown into the horn, a pressure test is much more accurate and informative."
I'm just sitting here laughing because this statement brings back old memories (55+ yrs) of a local clarinet repair person taking a big drag on his cigar and blowing smoke into the clarinet to see where the leaks were. And the "repaired" clarinet tasting like old cigar smoke for days afterward--yikes!! Ah yes, as Archie Bunker might say, "Those were the days" LOL
[sorry, couldn't resist this story]
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Author: BobD
Date: 2009-04-06 16:10
I've never heard of anyone complaining of clarinet leakage when he sucks on the mouthpiece. The point is that complaints of leakage stem from blowing into a complete clarinet and, to me, sucking to find leaks seems to be oxymoronic.
Yes, I know some swear by it but I consider the suck test another one of those old traditions that continue to be touted despite their non-sense. Maybe there is some rationale to it of which I'm not aware but blowing with or without cigar smoke still seems to make more sense to me. I have used soapy water to find non-pad related leaks.
Bob Draznik
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Author: DAVE
Date: 2009-04-06 16:33
One of my clarinets has no vacuum on the bottom joint but plays just fine. I thought about repadding it, but figured that if it plays to just leave it alone...
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Author: Arnoldstang
Date: 2009-04-06 17:16
The bottom of your horn is also long B in the staff. You want this note to resonate well without being stuffy. Again I feel the "suction test" may seem counterintuitive but it has some merit.. It is the duration the suction holds up that is the indicator. As far as the mouthpiece/reed suction test this is also sucking and not blowing. If you discount the efficacy of sucking air out of the instrument as a test then the same should follow for testing the mouthpiece/reed sealing.
Freelance woodwind performer
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Author: Gordon (NZ)
Date: 2009-04-07 22:17
"One of my clarinets has no vacuum on the bottom joint but plays just fine."
There is "just fine" and there is also BETTER than "just fine".
It depends on what the player is happy with.
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Author: tictactux ★2017
Date: 2009-04-07 23:16
EEBaum wrote:
> Indeed... there's "just fine" and then there's "HOLY CRAP ON A
> STICK, I DIDN'T THINK THIS INSTRUMENT COULD PLAY THIS
> NICELY!!!!"
With nice and competent repair people all over, the world would be a much noisier place. ![[tongue]](http://test.woodwind.org/clarinet/BBoard/smileys/smilie6.gif)
--
Ben
Post Edited (2009-04-07 23:16)
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Author: Rob Vitale
Date: 2009-04-09 17:39
try blowing while sealing. The pads are designed to stop air from getting out, not to stop air from getting in. If you blow air, you will hear the leaks clearly in a quiet room. If you hear a leak, get a wine cork and plug the bottom. You can use your free hand to apply pressure to different pads and find the leak this way.
hope this helps.
sorry, to answer your question, the vacuum should be tight on both joints. On my clarinets they are.
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Author: stevensfo
Date: 2009-04-09 18:54
-- "Yes, I know some swear by it but I consider the suck test another one of those old traditions that continue to be touted despite their non-sense." --
Who will be brave enough to suggest that there are many other traditions that deserve to be questioned? ;-)
I have to admit that I've spent ages trying the suck test after reading posts here, but I always go back to sticking a huge piece of blu-tac on to seal the end and blowing. With this and the cigarette paper test on each pad, I always find the leak. I have NEVER had any success with the suck test.
Steve
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Author: Rusty
Date: 2009-04-09 21:06
Well as I said when I cork the bottom section and suck into this bottom half of the clarinet with fingers down I get little vacuum on one instrument but perfect when I test my other clarinet. This immediately tells me ,does it not ,that I`ve got a leak. I may get a positive test also by blowing but how do I know whether it is a leaking pad or a weak spring?
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Author: tictactux ★2017
Date: 2009-04-09 21:34
Sure, if you suck and it won't hold the vacuum, then there is a leak.
If you suck and it does hold the vacuum, this doesn't mean that there is no leak under playing conditions.
--
Ben
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Author: Gordon (NZ)
Date: 2009-04-10 00:13
David: "Magnehelic machine is $300"
My mouth sensors are priceless, yet free for the using. :-)
All the magnehelic does is the same as a controlled blow test (i.e. mouthful of air only), but uses a number read-out instead of a whole lot of nerve messages from the sensors within the mouth tissue. Both detect loss of positive pressure.
Ben: Sure, if you suck and it won't hold the vacuum, then there is a leak.
If you suck and it does hold the vacuum, this doesn't mean that there is no leak under playing conditions."
And that second statement highlights the advantage of the blow test over the suck test.
Rusty: "I may get a positive test also by blowing but how do I know whether it is a leaking pad or a weak spring?"
The controlled blow test (i.e. mouthful of air only) is excellent for determining whether or not there are leaks.
If there are leaks, then blow with more pressure, direct from the lungs this time, until you hear air hissing out.
Press keys closed, one at a time, until you find the one that reduces the hiss. In most cases this will identify the location of your first leak.
Then check that pad visually and with a feeler, and check the tone hole edge for blemishes.
Check for friction issues such as a binding pivot, or a flat-spring running up against a tiny wall worn at the end of its groove, or rust on the spring, or simply too much friction on the surface of a flat spring, producing a "grip-slip" condition.
Spring tension is the most unlikely of the causes, unless you have carelessly de-tensioned it, eg by hooking the G#/D# spring to its cradle AFTER mounting the key on the instrument.
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Author: Rusty
Date: 2009-04-10 01:36
Gorden, it never occurred to me about a rusty spring. The one to the last pad before the bell is rust covered all over the suface. All other springs are rust free. I can see that this might retard the opening or closing. Ta, R.
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Author: Gordon (NZ)
Date: 2009-04-10 10:09
The friction from rust is mainly a problem on flat springs, but I suppose it can have an effect on needle springs too, especially if there is a rubbing action in the spring cradle, on account of the shape of the cradle and of the spring.
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Author: oliver sudden
Date: 2009-04-10 11:23
Rusty, when I lived in Sydney I visited this chap pretty often:
Steve Giordano
1 Wells Street, Annandale
NSW 2038
phone: (02) 9571 9086
He took good care of my hardware. He might have time to have a quick peek at your pad?
> With students Clarinets I'd rather not slobber in them.
Hm. It takes rather a lot of deliberate effort to get spit right down into a clarinet but did you maybe not mean this at face value? ;-)
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Author: BobD
Date: 2009-04-10 11:40
"when I cork the bottom"
I don't trust corks to make good air seals. I use rubber stoppers and even these don't always provide an adequate seal on some section ends. The "blu tac" mentoned is better.
Bob Draznik
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Author: oliver sudden
Date: 2009-04-10 12:12
"squeamish"?... then I think the pads are the least of their worries!
It's not spit, it's breath! (Spit only makes it at most a little way down the reed and if you're just checking for leaks not at all...) It's the soul! It's life! It's the 'anima'!
Gosh.
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Author: clarnibass
Date: 2009-04-10 12:32
>> As well, the machine gives a number to the leak amount. <<
If you want, I can tell you a number for the leak amount when I check it with my mouth.
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Author: oliver sudden
Date: 2009-04-10 13:22
> No, its not spit, but it is germs.
You can get those from a handshake though, no?
Just ignore me, I can see I've been hardened by my time in a country where cheese isn't ready until it's a bio-hazard...
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