Klarinet Archive - Posting 000068.txt from 2009/09

From: David McClune <dmcclune@-----.edu>
Subj: RE: [kl] Mouthpiece Bores
Date: Thu, 17 Sep 2009 10:44:59 -0400

Measuring a bore by eye is very silly and useless. The difference between =
a small bore and large bore mouthpiece exit bore is 100th of an inch! I us=
e a special set of calipers attached to a dial indicator. It has two arms =
which go out then the ends bend in opposite directions. I push it up the b=
ore to where the crown or cone starts (looking down the chamber in good lig=
ht to see), then read the measurement. I pull it to the exit and measure t=
here. THEN I start again and slowly pull the guage out noticing if the bor=
e taper is changing evenly or has parallel walls (some do) with another tap=
er. =20

You could spray the bore with "PAM" and push in modeling clay which drys. =
Take it out after drying and measure the plug, However you risk the mouthp=
iece (dahhh) and the tapered plug will still be slightly different from the=
actual bore because it has dried.

Does changing the bore taper change anything? Yes! The better question is=
does changing the bore taper make things better...it depends.

In making a mouthpiece everything you do changes something in the playing q=
uality. If you open up the top of the bore then you have to do "different"=
things in the chamber and facing to adjust the things that changed. Chang=
ing the bore may make better one aspect but mess up another aspect of the p=
laying. You have to rebalance everything. =20

Am I still experimenting with changing bore tapers in mouthpieces? Yes. H=
ave I found the Holy Grail...nope!

Reamers are custom made by machinists and easily made wrong. If you have $=
500-1000 laying around and can blow it, then get reamers made. However wha=
t tapers, what length, what shape of a crown...it just gets complicated and=
expensive. After you ream the bore, then what?

Best of luck

Dave

Dr. David McClune
University Professor of Music
Union University-1862
1050 Union University Drive
Jackson, TN 38305

731-661-5294
dmcclune@-----.edu

www.mcclunemouthpiece.com

-----Original Message-----
From: Karl Krelove [mailto:karlkrelove@-----.net]=20
Sent: Wednesday, September 16, 2009 3:34 PM
To: klarinet@-----.org
Subject: [kl] Mouthpiece Bores

I'll skip over the possible double meaning of "bores" for now - too easy.

Is there a standard way to measure the bore width and the taper of the back
bore of clarinet and sax mouthpieces short of cutting the mouthpiece in hal=
f
or renting time with expensive X-ray equipment? When I use a taper gauge
meant to measure barrels I'm not really sure what it's actually measuring -
is the gauge stopping at the narrowest point inside, or is it indicating th=
e
actual width at the opening, or is it hitting the back of the window and
just won't go in any farther (so I'd be getting some indication of the
distance from the end to the throat, but not a width measurement at all)?

I know lots of players who will hold a mouthpiece up to look through it and
declare it has a narrow throat or an open one, but that seems like looking
at the tip of a mouthpiece and deciding by eye how open it is. Are there
tools or instruments that can give more precise measurements at reasonable
cost (like a Brand gauge for bores)?

I'm interested in comparing mouthpieces, not getting an absolute
measurement. It would be interesting to know if certain pitch or timbre
tendencies of certain mouthpieces correlate to differences in bore
dimensions rather than those of the facing or the chamber.

Thanks for any input,
Karl

------------------------------------------------------------------

------------------------------------------------------------------