ASME Y14.5-2009 Errata sheet?

[3DDave]

Anyone have an errata sheet for ASME Y14.5 - 2009? I didn't see one on the ASME sales site.

I've started collecting errors, mostly from trying to diagram the definitions of datums and datum related terms that are scattered about. For example, 'True geometric counterpart' is supposed to have been eliminated between the '1994 version and the '2009 version, replaced by the term 'datum feature simulator' (A.6.5) but still is used in 4.16.5 and 3.3.3, but not defined elsewhere in the body of the standard.

Another are the borked cylindricity symbols back in Fig C-6.

Still not sure what distinguishes a Datum (1.3.13) from a Theoretical Datum (4.6) since a Datum is already defined as theoretical in nature. Word substitution would result in a Theoretical Theoretically Exact Point, Axis, Line, ...

 

[ctopher]

My guess is if there was one it would be on the ASME site.

Chris, CSWA
SolidWorks '15
SolidWorks Legion

 

[Belanger]

Found one today that I never noticed. In Fig. 3-29 there's no way the flange on the left end can be as large as 35-36 mm! That is way out of proportion from the other dims on the part. (Actually a student in my class pointed it out.)

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[tbuelna]

You can submit recommendations to the Y14.5 committee here:

 

[3DDave]

I know. They are not acted in a timely manner, certainly not to fix errors. Since each release is farther apart, 1982-1994-2009, the next release should be in 2027.

 

[3DDave]

1.3.60 Tolerance

tolerance: the total amount a specific dimension is permitted to vary. The tolerance is the difference between the maximum and minimum limits.

How does this definition fit in with a positional tolerance in which there may be no dimension or may be multiple dimensions involved locating a feature? There aren't really maximum and minimum limits that a positional tolerance depends on.

Suggested definition: the amount of variation that is acceptable in the finished product and expressed directly within dimensions or by using feature control frames. The value may be expressed as a single value, as a pair of limiting values, or be embedded as pre-calculated limit dimensions.

 

[3DDave]

datum reference frame symbol

It isn't a symbol as much as a notation on extension lines. This observation is supported in 4-24.13 where no mention is made of such a symbol that is in a diagram that is supposed to exemplify the symbol.

Mentioned in:
1) Figure 4-1 and 4-2 per 3.3.30 Datum Reference Frame Symbol
2) Figure 4-54 per 4.24.1 Datum Target Symbols

The notation appears in figures 4-7, 4-8, 4-28 4-42, 4-43, 4-44, 4-45, 4-46, 4-47. The notation is subsequently referenced only in figures 4-45 and 4-46 where modifiers depend on knowing the orientation of a coordinate system. In the other cases it is either not used or redundant to the coordinate system in the related computer based model where it provides possible conflict between the drawing and model.

Errata: in Figure 4-28 the direction of the x-axis changes from the 'this' to the 'means this' segment, making the 'means this' a left hand coordinate system while the 'this' segment is right handed.

 

[3DDave]

Geometric Dimensioning - Apparently the only concrete use of the term is in the title of figure C-3, Form and Proportion of Geometric Dimensioning Symbols, where it is applied to just four symbols.

 

[3DDave]

In the foreword is this:

To accomplish this it is becoming increasingly important that the use of geometric and dimensioning (GD&T) replace the former limit dimensioning for form, orientation, location, and profile of part features.

 

[akitasumo]

Figures in the standard are basically for reference only, see para 1.1.4

 

[powerhound]

akitasumo,
???

John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
SSG, U.S. Army
Taji, Iraq OIF II

 

[greenimi]

Figures in the standard are basically for reference only, see para 1.1.4

Yes, in the court of law, what’s matter, has relevance, substance and importance is the text only and not the pictures.

 

[CheckerHater]

in the court of law, what’s matter, has relevance, substance and importance is the text only and not the pictures

Does it mean that GD&T symbology is not defendable and only verbal notes have power?

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

 

[JNieman]

I think in the court of law, verbal notes are worth the paper they're written on.

_________________________________________
NX8.0, Solidworks 2014, AutoCAD, Enovia V5

 

[3DDave]

Figure 8-21, "Means this" is missing the outer boundary and the three datum indicating arrows point to empty space. Probably on a layer that was blanked or were set to white.

 

[CheckerHater]

Figure 8-21, "Means this" is missing

a, b, c, or d?

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

 

[Belanger]

CH -- I think Dave means Fig. 8-20.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

 

[CheckerHater]

Found it. I guess they will fix it in 2025 edition...

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

 

[3DDave]

Ahh yes - caught by the non-standard captioning -above- the image; should be 8-20.

Perhaps that's the largest running errata of all - placing captions ahead of what they caption. It's a development new to the '-2009 version.

 

[Belanger]

In paragraph 2.7.1(C), the first word should be "there" not "where."

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems