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Rackety Sax
05-31-2009, 05:01 PM
7 and 7* Link tenors differ by 5 thousandths of an inch. How much is this? According to this calculation found on Yahoo answers, about the thickness of a sheet of paper...


I have a package of 500 sheets of HP Bright White Inkjet paper. If I squeeze it together, it's about 60 mm thick, so we have the following:

thickness of 1 sheet = 60 mm / 500
= 0.12 mm
= 0.012 cm

According to a converter found on the web,
0.012 centimeter = 0.0047 inch or about 5 thousandths.

Anyone else surprised that the thickness of a piece of paper could account for a common "step" in mouthpiece tip opening?

SaxPlayer1004
05-31-2009, 05:22 PM
Go measure a bunch of STM's and you'll find some 6*'s that have bigger tips than 7*'s

It's a common step, but most people can't tell the difference.

Spooner
05-31-2009, 05:47 PM
A thousandth of one inch is .001"

It is just a simple move of the decimal place to describe one inch broken up into a thousand pieces.

The "standard" 7* opening is .105", which is .005" (or five thousandths) larger than a size 7 opening (which would be .100" -- or one hundred thousandths).

It is really shocking to see how much of a difference even .001" (in the right place) can make in the sound and response of a mouthpiece. The closer you get to the tip, the more impact subtle changes in the mouthpiece geometry can have on the sound.

mfry
05-31-2009, 05:54 PM
.005 just seems to be about the smallest step that most players notice on tenor. If it makes you feel better, it's 5% of .100.

oldcorollas
05-31-2009, 07:25 PM
one inch is 25.4mm
one thousandth of an inch is 25.4/1000 = 0.0254mm = 25.4microns

easier way to think about it is that 40 "thou" = 1mm (approx)
so 100thou = 2.5mm (2.54mm proper)

your paper measurement was pretty good :)
according to standard measurement = 0.122mm (http://www.i-tech.com.au/products/15327_HP_BRIGHT_WHITE_INKJET_PAPER_90GSM.aspx) or 4.5"mil"
just to confuse the issue more, 1 "mil" = 1 thousandth of an inch :P (not a millimetre.. which is called "mil" or "mils" for short in non-imperial countries)

it is not so surprising perhaps
going from jody jazz charts:
openings on alto go from 12 to 21 sheets of paper, a range of 9 sheets.
for tenor, roughly 14-28 sheets of paper, range of 14 sheets, but for a given mpc, usually about 11 sheets of paper range...
given that not so many people may play (in otto) 5's or 10*'s, that range is even smaller... say 7 sheets of paper

it kind of makes sense though, because for a given reed, there are 7 steps in hardness (maybe 4 or 5 within "normal" range), and in combination with the range of mpc, gives you more scope to fine tune the opening/hardness, but the actual number of steps is similar..

or....

Rackety Sax
05-31-2009, 08:00 PM
Gee, you guys sure know how to make a simple subject confusing. :)

I was just asking for a practical example of what .001" amounts to.

Here's another example I found on the web. I have no idea if it is accurate, since it isn't from Wikipedia. ;)


The thinnest [human hair thickness] is about 2 thousandth of an inch in diameter.
The thickest can be about 6 thou'.
Most is around 0.004 inches.

So a typical "step" in a mouthpiece is about the thickness of a typical human hair, if the above is accurate.

I doubt that most of us ever stopped to think what a subtle difference that is - at least I didn't.

Finnerski
05-31-2009, 08:49 PM
doubt that most of us ever stopped to think what a subtle difference that is - at least I didn't.

Unless you happen to be a machinist or tool and die maker. .005 is a mile for those guys.

Phil Barone
05-31-2009, 09:34 PM
7 and 7* Link tenors differ by 5 thousandths of an inch. How much is this? According to this calculation found on Yahoo answers, about the thickness of a sheet of paper...


I have a package of 500 sheets of HP Bright White Inkjet paper. If I squeeze it together, it's about 60 mm thick, so we have the following:

thickness of 1 sheet = 60 mm / 500
= 0.12 mm
= 0.012 cm

According to a converter found on the web,
0.012 centimeter = 0.0047 inch or about 5 thousandths.

Anyone else surprised that the thickness of a piece of paper could account for a common "step" in mouthpiece tip opening?

I love this question because it gives me a chance to cut loose. You can barely see a thousandth of an inch. Two thousandths is about the thickness of a hair so five thousandths is barely noticeable when playing a mouthpiece and whoever started that system was crazy.

When I make tenor mouthpieces I face them to one hundred thousandths and then when someone orders one I face it by hand to what they want and I play test it as I open it and file the baffle in and I don’t begin to feel the difference in opening until I reach eight thousandths. Now I know you’re thinking that you have different pieces with different openings and that you can feel the difference between a few thousandths between the two pieces but there’s other variables that contribute to how a mouthpiece feels like the height of the baffle near the tip and a bunch of other things but five thousandths is really nothing and when you factor in the difference in reeds, that some are softer and some are harder within a box these different strengths cancel out that measly little five thousandths.

There’s other things to consider too. When I or someone else gets a blueprint to make something, on the print there’s a number with a +/- symbol on it depicting the tolerance that the print or customer is willing to accept. So in the case of a part that doesn’t require a high level of precision you may have something that looks something like this: +/- = .005 which tell the machinist that the part can be accurate plus or minus five thousandths of an inch. The more accuracy the part requires the more expensive it will cost. Now saxophone parts don’t require a high level of accuracy like medical equipment, NASA, certain automobile parts like those used in racing etc. I’ve seen a Link that said #10 that was only .110 so it was .020 off. It should have been .130.

Another thing to consider is how a person is measuring it. A glass gauge with a metal feeler gauge isn’t enough and I’ve seen guys use things that didn’t make sense to me at all like a Vernier caliper because you can’t get a good handle on it and it slips easily and moves all over the place. Another thing to consider is where to measure it. Do you measure it toward the outer edge of the tip rail or toward the inside of the tip rail? If the tip rail isn’t flat the inside of the tip rail is going to be more closed than the outside. Who says that the tip rail is the same size throughout the entire length and width? The point is that it really doesn’t matter because once again the difference between reeds eclipse these minor differences. It wasn’t until the internet did mouthpiece techs start making an issue out of all these slight, minor, cosmetic flaws and issues in mouthpieces. I won’t go into that now but I know I’ll hear about it. Phil Barone

mfry
05-31-2009, 09:48 PM
I'll bite, Phil -- besides facing curve and tip opening accuracy (which you have made clear lately that you value less than some), what flaws do guys make an issue out of that you think are minor and cosmetic?

EZ
06-01-2009, 12:53 AM
Unit conversions:
http://www4a.wolframalpha.com/Calculate/MSP/MSP14121961ag46gg7f495200005g709e7ahea1g8b9?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14131961ag46gg7f4952000022gg2e625d53ch20?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14141961ag46gg7f4952000049g78hafhdcd93ef?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14151961ag46gg7f49520000252ga649gce8b63g?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14161961ag46gg7f495200000ge0ac40i19fgbg7?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14171961ag46gg7f4952000062c20d5c2493g83a?MSPStoreType=image/gif&s=21

Comparisons as length:
http://www4a.wolframalpha.com/Calculate/MSP/MSP14721961ag462318dd7b00004e4f871851cg355b?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14731961ag462318dd7b000054f9d26cci534e98?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14741961ag462318dd7b0000410e716c5be4fcg3?MSPStoreType=image/gif&s=21

Comparison as width:
http://www4a.wolframalpha.com/Calculate/MSP/MSP15991961ag4699a5if860000622510031h6g41aa?MSPStoreType=image/gif&s=21

Comparison as diameter:
http://www4a.wolframalpha.com/Calculate/MSP/MSP13871961ag4699d818190000362hghibb4cbgfeb?MSPStoreType=image/gif&s=21

Comparisons as light wavelength:
http://www4a.wolframalpha.com/Calculate/MSP/MSP14321961ag4699hbgchh00001ac1bc0df67f783a?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP14341961ag4699hbgchh00002gh60ggci1c439ai?MSPStoreType=image/gif&s=21

Comparisons as caliper:
http://www4a.wolframalpha.com/Calculate/MSP/MSP13691961ai23b2368f1b000066fcaac961251137?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP13701961ai23b2368f1b000052h763dfgh8i7i81?MSPStoreType=image/gif&s=21

Comparisons as fabric length:
http://www4a.wolframalpha.com/Calculate/MSP/MSP16091961ag4699a5if8600003a895dg8ebh0dfi1?MSPStoreType=image/gif&s=21

Electromagnetic frequency range:
http://www4a.wolframalpha.com/Calculate/MSP/MSP14751961ag462318dd7b000062ih58he36b05hag?MSPStoreType=image/gif&s=21

Corresponding quantities:
http://www4a.wolframalpha.com/Calculate/MSP/MSP13881961ag4699d81819000036d4gi9ageg57g7f?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP13891961ag4699d81819000012011b5c1d4f83ff?MSPStoreType=image/gif&s=21
http://www4a.wolframalpha.com/Calculate/MSP/MSP13901961ag4699d8181900005516c3adcdcd4d22?MSPStoreType=image/gif&s=21


Looks to be something close to a gnat's a**...

oldcorollas
06-01-2009, 02:45 AM
Two thousandths is about the thickness of a hair so five thousandths is barely noticeable when playing a mouthpiece and whoever started that system was crazy.

Phil, If you don't mind me asking..
If you were going to make mass produced mpcs that were not hand finished, and you wanted to make a range for anyone from a beginner to someone with iron lips, what range in openings would you choose, and how many steps within that range?
ie 80-120thou in 10thou steps? 20 thou steps?

Phil Barone
06-01-2009, 02:56 AM
Two thousandths is about the thickness of a hair so five thousandths is barely noticeable when playing a mouthpiece and whoever started that system was crazy.

Phil, If you don't mind me asking..
If you were going to make mass produced mpcs that were not hand finished, and you wanted to make a range for anyone from a beginner to someone with iron lips, what range in openings would you choose, and how many steps within that range?
ie 80-120thou in 10thou steps? 20 thou steps?

First, it's not about lip strength, more larger openings really require more air, not embouchure strength. Say we're talking about tenor. I would start with
.090 and work my way up in increments of .008 to whatever someone wanted. Phil Barone