drill holes in reflexes, make clamps (photo)

John B. writes:

The 0.002 mm requirement is insane. My "hand
tools" for measurement are not that accurate
by far and I don't have any motor driven
measuring tools either

No, not really. It equates to 1/10,000 of an
inch and you can measure that with a "vernier
micrometer" and I've seen work drawings with
tolerances in that range.

1/10 000 inch is 0.00254 mm so yes, that is
close to the guy's cube.

But my caliper is +/-0.03 mm and my micrometer
+/-0.01 mm so nowhere close!

--
underground experts united .... http://user.it.uu.se/~embe8573
Emacs Gnus Blogomatic ......... http://user.it.uu.se/~embe8573/blogomatic
- so far: 55 Blogomatic articles -

On 6/26/2016 11:12 PM, Jeff Liebermann wrote:
On Mon, 27 Jun 2016 08:57:38 +0700, John B.
wrote:

By the way, Walter Chrysler's tool box with a number of tools that he
had made himself used to be on display in the Chrysler Building.

Walter P Chrysler's Toolbox
https://www.flickr.com/photos/stuffbyxtine/3796829392

I like the Henry O. Studley Tool chest:
https://blog.lostartpress.com/2014/08/10/studley-tool-chest-exhibit-faqs/
https://lostartpress.files.wordpress.com/2014/08/studley_overall_img_0132-2.jpg
https://www.google.com/search?q=studley+tool+chest&tbm=isch

That's an example of what people can accomplish when they don't have a
TV to distract them.


--
- Frank Krygowski

On Mon, 27 Jun 2016 06:20:47 +0200, Emanuel Berg
wrote:

John B. writes:

The 0.002 mm requirement is insane. My "hand
tools" for measurement are not that accurate
by far and I don't have any motor driven
measuring tools either

No, not really. It equates to 1/10,000 of an
inch and you can measure that with a "vernier
micrometer" and I've seen work drawings with
tolerances in that range.

1/10 000 inch is 0.00254 mm so yes, that is
close to the guy's cube.

But my caliper is +/-0.03 mm and my micrometer
+/-0.01 mm so nowhere close!

I've never used a mm mike, but your description sounds very close to
what inch mikes, common and vernier, are.

But in many cases ultra small tolerances are not really necessary. I
hear people talking about "umpteenth of an inch tolerance" but my
guess is that even on a bicycle (High tech machinery) they aren't
really important. Back when I was in the trade a tolerance of +.001
-.000 was very rare, indeed.


--
cheers,

John B.

John B. writes:

1/10 000 inch is 0.00254 mm so yes, that is
close to the guy's cube.

But my caliper is +/-0.03 mm and my
micrometer +/-0.01 mm so nowhere close!

I've never used a mm mike, but your
description sounds very close to what inch
mikes, common and vernier, are.

But in many cases ultra small tolerances are
not really necessary. I hear people talking
about "umpteenth of an inch tolerance" but my
guess is that even on a bicycle (High tech
machinery) they aren't really important.
Back when I was in the trade a tolerance of
+.001 -.000 was very rare, indeed.

I never used one for fixing a bike - tho that
would be cool if such precision was needed -
but here I mention it because doing the metal
cube to a degree of perfection that cannot be
measured, at least not with the tools in my
possession - or put it this way, how would the
master verify the work of the apprentice when
he hands over the cube? Are there micrometers
and verniers that are more expensive that
carries more precision?

--
underground experts united .... http://user.it.uu.se/~embe8573
Emacs Gnus Blogomatic ......... http://user.it.uu.se/~embe8573/blogomatic
- so far: 55 Blogomatic articles -

On Tue, 28 Jun 2016 20:44:56 +0200, Emanuel Berg
wrote:

John B. writes:

1/10 000 inch is 0.00254 mm so yes, that is
close to the guy's cube.

But my caliper is +/-0.03 mm and my
micrometer +/-0.01 mm so nowhere close!

I've never used a mm mike, but your
description sounds very close to what inch
mikes, common and vernier, are.

But in many cases ultra small tolerances are
not really necessary. I hear people talking
about "umpteenth of an inch tolerance" but my
guess is that even on a bicycle (High tech
machinery) they aren't really important.
Back when I was in the trade a tolerance of
+.001 -.000 was very rare, indeed.

I never used one for fixing a bike - tho that
would be cool if such precision was needed -
but here I mention it because doing the metal
cube to a degree of perfection that cannot be
measured, at least not with the tools in my
possession - or put it this way, how would the
master verify the work of the apprentice when
he hands over the cube? Are there micrometers
and verniers that are more expensive that
carries more precision?

There are all kind of things that reach a higher level of accuracy
than a micrometer. "Gauge Blocks come in several classes".

Class (AAA): small tolerance (±0.05 um) used to establish standards
(AA): (tolerance +0.10 um to be used to calibrate inspection blocks
and very high precision gauging
(A): (tolerance +0.15 um to be used as toolroom standards for setting
other gauging tools
(B): large tolerance (tolerance 0.25 um to um20.15 \u03bcm) used as
shop standards for precision measurement

That "um" means micro meter. This computer won't make the "micro"
designation character.

I once saw an imaging device used to determine the accuracy of a gear.
You drew the outline of the gear, as accurately as possible, at, say
10 times the size of the actual gear on some sort of stabilized paper.
Then projected an image of the actual gear through an optical device
at a magnification of 10 times, onto the paper and the imperfections
were readily identifiable.

I've also seen a electronic "dial indicator" that read in increments
of 0.000001 inch.
--
cheers,

John B.

On 6/28/2016 9:53 PM, John B. wrote:

I once saw an imaging device used to determine the accuracy of a gear.
You drew the outline of the gear, as accurately as possible, at, say
10 times the size of the actual gear on some sort of stabilized paper.
Then projected an image of the actual gear through an optical device
at a magnification of 10 times, onto the paper and the imperfections
were readily identifiable.

Sounds like you're describing an optical comparator.
https://en.wikipedia.org/wiki/Optical_comparator


--
- Frank Krygowski

John B. writes:

There are all kind of things that reach
a higher level of accuracy than a micrometer.
"Gauge Blocks come in several classes".

Class (AAA): small tolerance (±0.05 um) used
to establish standards (AA): (tolerance +0.10
um to be used to calibrate inspection blocks
and very high precision gauging (A):
(tolerance +0.15 um to be used as toolroom
standards for setting other gauging tools
(B): large tolerance (tolerance 0.25 um to
um20.15 \u03bcm) used as shop standards for
precision measurement

That "um" means micro meter. This computer
won't make the "micro" designation character.

I once saw an imaging device used to
determine the accuracy of a gear. You drew
the outline of the gear, as accurately as
possible, at, say 10 times the size of the
actual gear on some sort of stabilized paper.
Then projected an image of the actual gear
through an optical device at a magnification
of 10 times, onto the paper and the
imperfections were readily identifiable.

I've also seen a electronic "dial indicator"
that read in increments of 0.000001 inch.

Ha ha, this sounds like some industrial complex
in East Germany! "Dial indicator" you say,
yeah, I should get one of those...

--
underground experts united .... http://user.it.uu.se/~embe8573
Emacs Gnus Blogomatic ......... http://user.it.uu.se/~embe8573/blogomatic
- so far: 55 Blogomatic articles -

On Tue, 28 Jun 2016 23:20:23 -0400, Frank Krygowski
wrote:

On 6/28/2016 9:53 PM, John B. wrote:

I once saw an imaging device used to determine the accuracy of a gear.
You drew the outline of the gear, as accurately as possible, at, say
10 times the size of the actual gear on some sort of stabilized paper.
Then projected an image of the actual gear through an optical device
at a magnification of 10 times, onto the paper and the imperfections
were readily identifiable.

Sounds like you're describing an optical comparator.
https://en.wikipedia.org/wiki/Optical_comparator

Yes, but I thought I should explain it a bit. It was at Fellows Gear
Shaper in Springfield, Vermont. I was told that it was the first
company to "generate" a gear.
--
cheers,

John B.

On Wed, 29 Jun 2016 06:03:02 +0200, Emanuel Berg
wrote:

John B. writes:

There are all kind of things that reach
a higher level of accuracy than a micrometer.

I've also seen a electronic "dial indicator"
that read in increments of 0.000001 inch.

much previous material deleted

Ha ha, this sounds like some industrial complex
in East Germany! "Dial indicator" you say,
yeah, I should get one of those...

Well, it had the finger that rested on the work and a round gauge but
everything else was electronic :-)
--
cheers,

John B.

On 6/28/2016 11:03 PM, Emanuel Berg wrote:
John B. writes:

There are all kind of things that reach
a higher level of accuracy than a micrometer.
"Gauge Blocks come in several classes".

Class (AAA): small tolerance (±0.05 um) used
to establish standards (AA): (tolerance +0.10
um to be used to calibrate inspection blocks
and very high precision gauging (A):
(tolerance +0.15 um to be used as toolroom
standards for setting other gauging tools
(B): large tolerance (tolerance 0.25 um to
um20.15 \u03bcm) used as shop standards for
precision measurement

That "um" means micro meter. This computer
won't make the "micro" designation character.

I once saw an imaging device used to
determine the accuracy of a gear. You drew
the outline of the gear, as accurately as
possible, at, say 10 times the size of the
actual gear on some sort of stabilized paper.
Then projected an image of the actual gear
through an optical device at a magnification
of 10 times, onto the paper and the
imperfections were readily identifiable.

I've also seen a electronic "dial indicator"
that read in increments of 0.000001 inch.

Ha ha, this sounds like some industrial complex
in East Germany! "Dial indicator" you say,
yeah, I should get one of those...


A verier or dial expands the reading between two marks to a
finer increment than can be readily seen. Modern digital
readout models can go to extremes in that regard, very
useful for jet engine manufacturing, more information than
you need for most bicycle work.

Derailleur chain length for example, runs in one inch
increments so even if you determine an 'ideal length' at
112.3864 links you'll have to choose either 112 or 114 links.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971