Is "typical opposite side" still legal?

[jeff97070]

I have a rectangle sheet metal part with two flanges one on each side bent the same direction and each flange has a hole of the same size at the same locations.

Showing the front view and then a right and left view in the drawing can you dimension one view and then say typical opposite side?

Thanks.

 

[KENAT]

TYPICAL - or TYP is not explicitly supported by the current ASME Y14.100 series drawing standards so I'd avoid it.

Not sure I follow your entire post but why not just '2X' on appropriate dimension(s)?

Posting guidelines faq731-376

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(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[powerhound]

Per ASME Y14.5, no. The use of "TYP" is not supported at all.

John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
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[CheckerHater]

But you can draw only half of the part and declare it symmetrical. See Y14.5-2009 Para 1.8.9, Fig. 1-35

 

[ewh]

If the flanges are bent the same direction, it would not be symmetric. I agree with KENAT; the easiest out may be to add "2X" to the appropriate dimensions and double the qty at the hole callout.

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

 

[fsincox]

The GD&T people I was taught by always said: "remember when all else fails you can always go back to adding notes to clarify". I am not aware of any real prohibition against using notes for anything! The intent of the symbolic notations is to standardize some of the more common terminology. How about 2 holes going through 2 opposed flanges then what does 2X actually mean, symbolism has its limits, too. I say yes! it is legal, I am not guarantying any note you write will be commonly understood by anyone!. The biggest problem I see with standards is they can't cover everything.
Frank

 

[powerhound]

I agree that notes should certainly be used "when all else fails". That is not the case here though. I can think of at least two other, standard supported ways to define the hole locations that would not require a note. Thus, "all else" has not failed.

John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II

 

[ctopher]

I would use 2X.

Chris, CSWA
SolidWorks 14
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[fsincox]

The question was "is it legal", I say yes! Show me where you find any prohibition statement, please!
Is it OK to use "2X" for inline holes (not coaxial) also? I see this done all the time but it is not shown in the standard. Everyone knows what THEY think "2X" means!
Frank

 

[powerhound]

Frank,

I know what the OP question was. "Is it legal?" isn't in it. Neither did I say it was illegal to use. All I said was that its use was not supported in the standard. I still haven't said it was illegal to use and neither has anyone else who has responded. I don't know why you're asking me, or anyone else, to show you where it's use is prohibited.

My last response was based on your statement "When all else fails.." That's exactly what you said, no extrapolation required. My response was that "all else" had not failed. There are ways to do what the OP is asking about that are completely supported by the standard.

Relax dude, and don't be so defensive...with all your exclamation points.

John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II

 

[Belanger]

powerhound: I pretty much agree.
But ... read the subject line of the thread.

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

 

[fsincox]

ANSI Y14.5M-1982 1.9.5. (this is when the standard actually changed) "Repetitive features or dimensions MAY be specified by...", as opposed to must. 1994 & 2009 use the same words.
Frank

 

[powerhound]

JP, thanks for catching that. My apologies to you, Frank, for missing it. Strike that sentence from the record.

I've always had a problem with the use of soft words like "may" and "should" in the standard. It gives people license to do whatever they want in a situation such as this with no direct prohibition of it. The entire standard is, however, voluntary. So you can either use it, or not. If someone is going to use it, then they should--but they don't have to--use concepts and techniques that are fully supported so that there is no confusion or ambiguity later on down the line. Using unsupported techniques and then playing the "may" or "should" card, does not by default support said technique. It is still unsupported.

John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II

 

[fsincox]

Powerhound,
I completely support the use of symbollic notations for things. In real life I find I need lots of tools in my tool kit and do not like to give any of them away.
The standard tends to show fairly simple parts that do not need much else. The real world is not so cut and dry.
I constantly see people use "?X" for holes in a line, the last time I looked the standard has no example showing it used like that, I supose that falls under repeated dimension, but I would like to see it shown then. I see it for coaxial holes and repeated pattern dimensions but not holes in a line, I think it can get confusing too.
++++++
+++
++
Is this 2X or 3X or 6X, clear as mud, right! Now space them apart and put other holes in between! that is the real world.
Frank

 

[CheckerHater]

Frank,
What is your distinction between "coaxial holes" and "holes in line"?

 

[fsincox]

CH, I am sorry, it is the only terminology I could think of. If you look at the pattern I laid out above I have 6 centers "inline", 3 centers "inline" and 2 centers "inline". From the other direction I have 3 centers "inline", 3 centers "inline" and 2 centers "inline" (sharing a common dimension?).
I agree that coaxial holes are inline, too. For example: in ASME Y14.5M-1994,fig 5.51 they do not show a 4X on either of the hole locating dimensions. I have yet to see anywhere in the standard they do that to holes shown dimensioned "on a common line", but in the real world I see it all of the time.
Frank

 

[ewh]

In fig 5.51, the centerline is common, thus needs to be located only one time.
In your linear example, if there was a common centerline you would use one dimension to denote either horizontal or vertical spacing. I often see individual centerlines used in linear patterns, with the appropriate qty added to the locating dimensions. I use a common centerline as often as reasonable, eliminating the qty requirement on that locating dimension.
This is a fine example of how the standards are more of a "dictionary" than a textbook in regards to producing a "good" drawing.

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

 

[fsincox]

Agreed, All of the examples in the standard use that method. I also follow that practice, myself, actually. I have always felt there should be another option and, if you are following from the OP, that a note of reference fit this requirement also (2). This takes us back to the note question which I have been advocating as an valid option.
Frank

 

[CheckerHater]

Thank you Frank, I wasn't sure what you meant by "inline".
I agree, unfortunately standard is not always clear.
If you look at Fig. 7-5 in 2009, you'll see that verbal note "thru both sides" still alive and well. Is it one hole thru both sides, or two holes in both sides?

 

[fsincox]

CH,
Perfet example of their attempt to use a note clarify intent. I know note are not perfect either, but really you run into the same issues with ?X.
Thank you,
Frank