Stupid question

[CheckerHater]

We all know that, and proud of this knowledge, but is there place in Y14.5 where placing datum feature symbol on axis is explicitly forbidden?

Just in case I need to point someone's nose into it?

Thank you.

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[greenimi]

6.3.2/2018
The datum feature symbol shall not be applied to center lines, center planes, or axes.

 

[pmarc]

ASME Y14.5-2018, para. 6.3.2:
"The datum feature symbol shall not be applied to center lines, center planes, or axes."

 

[greenimi]

pmarc,
I beat you by a minute!!!!

 

[pmarc]

greenimi,
Other than "congratulations", what else can I say?

I have a feeling that a follow up question is coming from CH very soon.

 

[geesaman.d]

On a practical level it should be common sense that a datum is actual geometry, and an axis is not. In fact, there are frequently multiple circular features on a common axis, so it could only be functional in the limited situations where there is only one cylindrical feature on that axis.

 

[axym]

Hi All,

Another way to think of it is that centerlines, center planes, and axes are not datum features. They're datums.

Evan Janeshewski

Axymetrix Quality Engineering Inc.

http://www.axymetrix.ca

 

[CheckerHater]

Thanks a lot!

Sorry pmarc, I am too old to play games now.

By the way, what kind of question were you expecting?

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

 

[BiPolarMoment]

By the way, what kind of question were you expecting?

"Something something symmetry is implied." ?

 

[pmarc]

CH,
I expected the same question but about Y14.5-2009.

 

[greenimi]

I expected the same question but about Y14.5-2009.

I cannot find a similar statement in the 2009. Am I missing it?
Or it is in a different part of the standard then Symbology?

 

[pmarc]

I cannot find a similar statement in the 2009. Am I missing it?
Or it is in a different part of the standard then Symbology?

There is no similar statement in 2009 as far as I can tell, only some hints.

In para. 3.3.2:
"The datum feature symbol is applied the feature surface outline, extension line, dimension line, or feature control frame..."

In para. 4.24.13:
"The datum feature symbol should be applied be attached only to identifiable datum features."

 

[3DDave]

4.8.2 '2009.

 

[pmarc]

Thanks, 3DDave.

 

[mfgenggear]

yet old school it was a common on shafts to specify datum to centerline. -A- centers and still is

 

[DraftingMan]

ASME Y14.5M-1994 - 4.3.2

JHD

 

[DraftingMan]

ASME Y14.5-1982 - 4.2.2


JHD

 

[mfgenggear]

https://rarehistoricalphotos.com/life-before-autocad-1950-1980/