On 11/24/2013 12:45 AM, Gunner Asch wrote:
On Sun, 24 Nov 2013 00:20:47 -0600, Richard
wrote:

On 11/24/2013 12:00 AM, Gunner Asch wrote:
On Sat, 23 Nov 2013 23:33:15 -0500, "Mike Marlow"
wrote:

Gunner Asch wrote:


Ayup...aerospace requires 50 millions or half 10ths all the time.

Which is damned hard to do with machines that hold +/- 2 tenths


One might think it is impossible to do with repeatability and assurance.

Hardly impossible. It happens many thousands..hundreds of thousands
of parts a day.

So - I am curious - what is it that aerospace requires that is 50
"millions"? I worked in that space for a while and I never saw any
tolerances like that - but that does not say much. I believe that even the
space shuttle does not demand tolerances that close - but I really do not
know.

Jet engine parts, microwave wave guides, thousands of things. Most of
which I was not cleared to know what they were when I ran into them..
An awful lot of optical stuff is that or more.

Shrug. And a lot of that stuff I figured would be good at
+0/- .001...but..the specs...

As the truism goes...the more zeros you add to the right of the
decimal point...you multiply the cost by a factor of 5-10


Half a thou? (NOBODY says 50 millionths!)

Half a thou isnt 50 millionths. Its only 5 tenths.
Half a tenth..is 50 millionths.

I really hate to get in to this with all of you exactimundo types with
all your close tolerances but "Half a thou is not 5 tenths"

..001 / 2 =.0005 not .5

and half a tenth is not 50 millionths,

..1 / 2 =.25

Or maybe you guys are using a different kind of math....