ORDINATE DIMENSIONING PER ANSI Y14.5 1998 6

[drawoh]

BUGGAR and jgKRI,

Are your machine operators carefully reading dimensions off your drawing, or are they using the geometry off the drawing?

--
JHG

 

[SwinnyGG]

Both are possible, depending on the scenario.

We deal with a LOT of one-of-one work where it's faster to program manually.

 

[Belanger]

The above figure violates ¶1.7.1.4

Sorry to dig back into this thread, but that Figure 5-4 does not violate 1.7.1.4, simply because that paragraph says "should" and not "shall" avoid crossing dimension lines. Recall the difference between those two words -- maybe this picture is an instance of the "unavoidable" situation they mention?

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

 

[ewh]

Did you read all of my post JP?
Last line was "It is not "shall" but a "should" and there are many situations where it just isn't worth the effort. When it can easily be done though, it should be."
If it doesn't make a difference in drawing interpretation, why include ¶1.7.1.4 in the standard at all?


"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

 

[BUGGAR]

I just called one of the operators. Since he has worked with me before, he doesn't even look at the nice drawings I send him but just puts my dxf file in the waterjet cutter drive. Then, on the machine screen, he puts my file visually where ever he wants it, with no regard to my 0,0 point. This is where he nests the parts (some machines can do this automatically) and even combines my parts with my competitor's parts (horrors). I once forgot to properly place a part and its coordinates were up in the 100,000's but that didn't even cause a pause.

 

[Belanger]

ewh -- no, that's not quite what you wrote. I didn't see any use of the words should or shall.

I agree with your general premise: a figure in the standard doesn't have to toe the line in every darn rule if it's just trying to illustrate a specific point. But it's too strong to write that the figure "violates paragraph 1.7.1.4."

The reason they give paragraphs stating "should" rather than "shall" is to give guidelines. It's nice to have guidelines to follow that aren't enforceable in the way that a full law would be.

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

 

[ewh]

JP
That is what I added in the edit I did immediately after posting (16OCT18). I do agree that "violates" was too strong an incorrect characterization. If the detail shown was on a drawing, I would mark a comment that the situation could easily be avoided, unless there were other views/dimensions that were crowding that detail. Without some sort of guidance for those creating the drawings, unnecessarily crossing dimension lines will become standard practice (I see it happening on almost every drawing I check). It is not a big problem, but it is one of the smaller things that contribute to ease of drawing interpretation.

edit: added relevant posting date

"Know the rules well, so you can break them effectively."
-Dalai Lama XIV

 

[Belanger]

ewh -- to be clear, that "edit" was nearly one month after your post about violating 1.7.1.4 (Sept. 18).
So I admit that I didn't scroll down 11 posts later to see your follow-up. At any rate, all is well...

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

 

[pylfrm]

I just called one of the operators. Since he has worked with me before, he doesn't even look at the nice drawings I send him but just puts my dxf file in the waterjet cutter drive.

I assume the nice drawings get a quick glance to determine material type and thickness at least. What about tolerances?


pylfrm

 

[greggula]

Just don't put an extension line through the arrowhead of another leader line or dimension LOL.

 

[BUGGAR]

"I assume the nice drawings get a quick glance to determine material type and thickness at least. What about tolerances?"
Actually, on the stuff we have set up for production, we have a coded file name which references that required information. We're looking to really streamline production and it works pretty well. (Mostly. I told you about my sculpture garden displaying my mistakes.)
I now realize water jet cutting does not require a 0,0 on your dxf drawing. What about X,Y CNC drilling machines?