Drawing scale call out for isometric drawings

[marshell]

What is the standard for showing the scale on a drawing that has only an isometric view? Should the scale be the cadd generated scale, or should the title block be changed to show "NONE" for the scale? And for drawings that have orthographic views, and an iso off in a corner somewhere... should the iso contain a label that says "SCALE: NONE". Are iso views considered to be to scale even though the cadd program has created them as foreshortened?

Thank you in advance.

 

[ctopher]

I usually indicate scale. If it shows some type of label or marking/etc, I will indicate "SCALE: NONE".

Chris, CSWA
SolidWorks 14
ctopher's home
SolidWorks Legion

 

[Tunalover]

I believe that a scale should be indicated but only if it's different from the scale indicated in the drawing format.


Tunalover

 

[drawoh]

marshell,

If your drawing actually is isometric, you can measure off it with a scale, and you need to show the drawing scale. If you just did a 3D view like I generally do, showing the drawing scale is nice, but not necessary[ ](n³)!

--
JHG

 

[marshell]

Are Isometric views considered to scale? The cad program (Solidworks in my case) is generating the iso views with a foreshortened method (approx .8 scale, or the SgRt of 2/3). So there will be a variance if I attempted to retrieve a measurement using a scale ruler from the iso view generated.

 

[CheckerHater]

The cad program (Solidworks in my case) is generating the iso views with a foreshortened method

If you draw a sphere 1 in in diameter in SolidWorks, what size the sphere will appear in iso view?

 

[marshell]

I created a 1 x 1 x 1 cube and created orthographic views, and an iso view. From the attached you can see the iso lines as slightly smaller (.82 per my trusty calipers).

so the question becomes... Should the iso view have the notation "Scale: None:" below it?

 

[ewh]

marshell,
Foreshortening is an accepted of showing iso views (per ASME Y14.3-2012). As for scaling dimensions from the drawing, it is almost universally forbidden (though of course it does happen). One solution (to what shouldn't be a problem) is to label the views as "FORSHORTENED ISO VIEW" instead of just "ISO VIEW".
The scale should still be included if different from title block scale.

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

 

[CheckerHater]

From the attached you can see the iso lines as slightly smaller

From the attached I can see that the red lines are exactly the same. Who told you your iso view is out of scale?

And what happened to the sphere?

 

[3DDave]

Many drawings have a note that tells the user not to scale it and then includes a scale. I'd prefer drawings to have no scale indicator on them. That's what the dimensions are for. If you need them, then magnification amounts are useful for detail views that show small items magnified, but not a global scale.

It's a waste of time given the rarity of anyone getting hold of a drawing reproduced at any particular scale.