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pool_shark69
07-20-2005, 02:18 AM
I work at A Machine shop in Mark ill. We get little training. I have been doing this kind of work for over a year and i still call myself a PUSH BUTTON OPERATER!! I am dealing W/ the fact that set-up, and maint. are to do all the fun stuff. But they made a guy a cell facilitater(guy that walks around and helps operaters with problems)that says .00005 is not fifty-millionths. Now i asked my supervisor and he said im right. But the guy said to go on line and look it up, cuz there wrong. Please tell me what it actually is. I just love my job and want to learn it better the right way. Thanks

07-20-2005, 02:46 AM
Tell that "cell facilitator" dweeb if he can't work decimals he doesn't deserve a fancy title.

You're right. 0.00005 is 50 millionths. The decimal progression is in multiples of ten as the numbers move to the right of the decimal point. As we in the machine shop express it: tenths of an inch (one decimal place), hundredths (two places), thousandths (three places), ten-thousandths (four), ten of millionths (five), millionths or micro-inches (six decimal places).

IOWOLF
07-20-2005, 04:02 AM
OK,Forrest is correct. But really whats the point? Do you work to that tight of tolerances?Most places only deal with 4 decimal places.

IMHO

pool_shark69
07-20-2005, 10:25 AM
thank you for the correct answer. and yes on one job we run spline shafts and only get+.00025 -.00025 and have to offset in.00001. Iguess the point is just for my own satisfaction, of knowing a man thats 40+ years old, been doing this work for a little while and is wrong. You would have to meet the guy and then you would want to prove him wrong to. He is a cocky noit all.

[This message has been edited by pool_shark69 (edited 07-20-2005).]

[This message has been edited by pool_shark69 (edited 07-20-2005).]

[This message has been edited by pool_shark69 (edited 07-20-2005).]

[This message has been edited by pool_shark69 (edited 07-20-2005).]

Paul Alciatore
07-20-2005, 01:03 PM
I don't like that type myself but remember that we all have our strong and weak points.

Paul A.

IOWOLF
07-20-2005, 01:54 PM
There was a guy on here a while back who had a guy named "Pete" I think,He was asking what he should do about him,there was all sort of advice , you might look in the archives for advice on him.

Becouse there is at least one on every job.

07-20-2005, 06:53 PM
Hey you guys! Watch how you talk. Us cocky ni-it-alls have sensitive feelings.

07-20-2005, 07:10 PM

Is'nt 50 millionths .000050? Without the 0 after the 5 would the value not be 5 hundred thousandths? The 0 after the 5 is a significant figure, and reflects greater precision in the measurement. On the other hand I could be clueless.

Wirecutter
07-20-2005, 07:23 PM
I always thought it boiled down to whether you're talking to a scientist (achademic) or an engineer. HP calculators have settings for FIX, SCI, and ENG which determine how decimals are displayed. The difference between SCI and ENG is that ENG makes the exponent a multiple of 3, so you see thousanths, millionths, billionths, etc. (Ok, milli-, micro-, and nano-...) The SCI setting likes to put a single digit to the left of the decimal, the rest on the right, and adjust the exponent to make it all fit.

I know it sounds like gobbledigook to type it out like this, but when speaking, it's easier to say "millionths", "thousanths" etc than it is to say "ten-thousanths", "hundred-thousandths", etc. I guess that makes me an engineer. I'd rather say "50 millionths" than "five hundred-thousandths" or perhaps more correctly, "five one-hundred-thousanths".

What did the "cell operator" say .00005 is?

-M

07-20-2005, 07:49 PM

ok, let me see if i get this right.

if, .00005 is fifty millionths
then, .000005 is five millionths
and, .0005 is five hundred millionths?

and, .000045 is fourty five millionths

and, .000455 is four hundred fifty five millionths?

how about .004, thats four thousandths. then .04 is fourty thousandths?

*brain swelling*
*emergency shutdown*
*turn off computer*

pool_shark69
07-21-2005, 01:25 AM
Yes im a noob, i said that i have only been doing this kind of work just over a year. sorry.
The guy told me tonight that .00001 is one- one-hundredth of a tenth. i guess there are a lot of different formats for decimals. Anyway he did apoligize for being cocky about it.

[This message has been edited by pool_shark69 (edited 07-21-2005).]

Scatterplot
07-21-2005, 01:59 AM
That's not one hundredth of a tenth. It's one thousandth of a hundredth, or a ten-thousandth of a tenth. a Well unless you're talking about a tenth of a thousandth being "a tenth," in which case it's one tenth of a tenth. Then again, combining them it could be a tenth (slang term) of a tenth (technically correct term).

OK, hang on, my brain just gnawed it's way out of my head.

fpressly
04-18-2014, 10:11 AM
Q: I hear metal machinists talk about tenths and thousandths. Can someone tell me the right way to say .00005"? I know in scientific jargon that would be 5/100,000th of an inch. Can anyone tell me the correct method of saying it in machinist talk?

A:

To a trained machinist (NOT USING THE METRIC SYSTEM), that is "half a tenth" of an inch.

The increment of measurement used in all metal machine shops, is a thousandth of an inch (.001). Often referred to as "a thousandth". You have 1-1000 of them in an inch.

.0001 is a tenth of .001 and therefore referred to as a "tenth" [of a thousandth]. The next level .00001 is a tenth of .0001, so that would actually be a tenth of a tenth. Although no machine shop could hold tolerances of .000001 that would technically be a "tenth of a tenth of a tenth." Follow the logic?

Everything in a machine shop is discussed in terms of 10s, 100s and 1000s (no million, billon, trillion). There really is no need for millionths, billionths and so forth because nothing in machine shops hold to those tolerances. Those tolerances are maybe finishes or something; but, real shop work stays in the "thousandths" range and "tenths" range if you really are working tight.

So .00005 is "5/10 of a tenth" or "half a tenth of a thousandth". or just

"half a tenth" to the properly trained individual.

Source:

25 years experience

5 out of 5 Brilliant! Thanks that helps a lot.

loose nut
04-18-2014, 10:44 AM
So where do Ha'pennies enter into it.

Jaakko Fagerlund
04-18-2014, 10:54 AM
Holy resurrection.

Alistair Hosie
04-18-2014, 04:31 PM
Haaa'pennies are what John his ludship Stevenson spends on a good night out. Alistair

Paul Alciatore
04-18-2014, 04:41 PM
fpressly, I see that is your first post. Welcome to the group. I guess you are reading the archives. Or you landed on it via a web search.

To answer your question, the various positions in the decimal order of digits can be referred to in different ways. As someone stated above, many calculators have the ability to express them in the manner that different professions use them. Thus engineering vs. scientific displays.

As for your question, what do you call 0.00005", I suspect that different professions would speak it differently. A lay person may say zero point zero zero zero zero five inches. A scientist may say five hundred thousandths or five times ten to the minus five. Engineers loke to work in tiers of three (hundreds, thousandths, millionths, billionths, etc) so an engineer may say 50 millionths. And a machinist may say half a tenth. ALL are equally right and all are equal amounts. For better or worse, we need to be aware of the various ways of saying this and of the fact that they are all correct.

There is a more confusing place in all of this and that is the machinist's use of the word "tenths". In a strict sense, that could be taken as 1/10 of an inch, but no machinist would ever think that is what the word means. They would always assume you are talking about a tenth of a thousandth (0.0001") because they are almost always working in thousandths. The thousandth is their standard unit. But, to the uninitiated, this could be confusing.

It's a wide, WIDE world and we need to learn to live in it.

boslab
04-18-2014, 05:38 PM
We say it "four noughts five" over here, least everyone i know does, asked a similar question to an instructor once, he said its half of three noughts one, or half a gnats cock between two sheets of plate glass, micro inches comes to mind too, but not certain, at that amount of zeros your measuring the surface texture, im buggered if ive ever machined anything to that, i dont even think slip gauges have that sort of tolerance, they just make them lap them and measure them and sort them into bins of tha size they are, they don't try to make them to size, hopefully 1 std deviation, think thats 68 % come out to size but i forget all the useful crap i once knew, they use the normal distribution curve, after gauss the math wizard
Mark

Doozer
04-18-2014, 05:43 PM
Holy resurrection.

It is Easter.
Time to rise up.

-Doozer

PStechPaul
04-18-2014, 06:13 PM
Confucius say: "The baker whose boy falls asleep in the dough, find the Son rises in the yeast!"

loose nut
04-18-2014, 07:17 PM
fpressly, I see that is your first post. Welcome to the group. I guess you are reading the archives. Or you landed on it via a web search.

To answer your question, the various positions in the decimal order of digits can be referred to in different ways. As someone stated above, many calculators have the ability to express them in the manner that different professions use them. Thus engineering vs. scientific displays.

As for your question, what do you call 0.00005", I suspect that different professions would speak it differently. A lay person may say zero point zero zero zero zero five inches. A scientist may say five hundred thousandths or five times ten to the minus five. Engineers loke to work in tiers of three (hundreds, thousandths, millionths, billionths, etc) so an engineer may say 50 millionths. And a machinist may say half a tenth. ALL are equally right and all are equal amounts. For better or worse, we need to be aware of the various ways of saying this and of the fact that they are all correct.

There is a more confusing place in all of this and that is the machinist's use of the word "tenths". In a strict sense, that could be taken as 1/10 of an inch, but no machinist would ever think that is what the word means. They would always assume you are talking about a tenth of a thousandth (0.0001") because they are almost always working in thousandths. The thousandth is their standard unit. But, to the uninitiated, this could be confusing.

It's a wide, WIDE world and we need to learn to live in it.

You could also say it is a wee bit less then a thou. and still be close enough for most.

macona
04-18-2014, 08:18 PM
Here is half tenth or fifty millionths.

ulav8r
04-18-2014, 11:36 PM
When I worked in a Vickers pump and motor plant, it would be called 50 millionths. That was my first exposure to measurements that small.

Paul Alciatore
04-18-2014, 11:43 PM
Everywhere it is too small to see. And usually to bother with too.

J Tiers
04-19-2014, 01:19 AM
What it really is is too daggoned small to worry about unless you are dealing with gage blocks and optical flats...

But the "walk around guy" has his head in a dark place..... so long as you are talking inches.

becksmachine
04-19-2014, 02:18 AM
fpressly, I see that is your first post. Welcome to the group. I guess you are reading the archives. Or you landed on it via a web search. .................................................. .................................................. .................................................. ..It's a wide, WIDE world and we need to learn to live in it.

Very eloquently put, good on you! ;)

However, I have seen no mention of mils, so in an effort to make the inventory of confusion (more?) complete, I thought I would.

Dave

Peter.
04-19-2014, 02:42 AM
0.00005

That would be 'half a tenth' to me but if I ever saw one I'd call it 'Sir' :)

mike4
04-19-2014, 07:08 AM
Haaa'pennies are what John his ludship Stevenson spends on a good night out. Alistair
And thats after he has been shouted a few pints.
Michael

Jaakko Fagerlund
04-19-2014, 02:34 PM
0.00005

That would be 'half a tenth' to me but if I ever saw one I'd call it 'Sir' :)
I have seen it. On the outside layer of my workpiece, and it talked, too! He said "I don' wanna go in that hole" :D

Baz
04-19-2014, 05:40 PM
Very eloquently put, good on you! ;)

However, I have seen no mention of mils, so in an effort to make the inventory of confusion (more?) complete, I thought I would.

Dave

Well I'm confused. How many Angstroms are we talking here?

Jaakko Fagerlund
04-19-2014, 05:56 PM
Well I'm confused. How many Angstroms are we talking here?

fpressly
04-19-2014, 08:00 PM
0.00005

That would be 'half a tenth' to me but if I ever saw one I'd call it 'Sir' :)

Yessir, I think anyone holding half a tenth tolerance, is to be commended and called Sir.

fpressly
04-19-2014, 08:01 PM
Well I'm confused. How many Angstroms are we talking here?

Well if you really want to know lets see...

"half a tenth" is precisely 12,700 Angstroms.

KJ1I
04-19-2014, 11:06 PM
Back in the day, working at TRW Space Systems, we (they) had a stone (in a clear room, key card access only) that was accurate to 1 one millionth of an inch across its entire length. I don't remember if it was 3 feet or 4 feet long. I also don't remember what it was used for - and while in my position (top secret clearance, electronics maintenance) I had access to most of the rooms on site, I didn't have access to that one. But I could look through the window and watch them work - with only their eyes showing.

garyhlucas
04-19-2014, 11:32 PM
0.00005 inches is about 50 times more expensive than 0.001 inches!

PStechPaul
04-20-2014, 01:01 AM
"Less is more!" ;):rolleyes:

Where I once worked, we had a slacker named Les. I found an advertising poster that said "Making Less do More". I scratched off one "s" and posted it by his desk. He did not appreciate the humor, but most of us did.