"TRUE LENGTH" call out

[Dave K]

Is there a standard (or abreviation), to explicitly state that a dimension is the true length?

Scenario: I have a bent tube, with bends in more than one plane, ie compound bends. I have my main views showing the entire tube, but my auxiliary views, which show certain sections of tube in their true view, are only partial, to save space. I want to make sure the vendor knows that the length in that view is the true length. It should be obvious from the direction the view is taken, but not knowing the vendor, I't like to "idiot proof" things as much as possible. I'd also like to do this via some standard, if one exists, for the same reason.

Is there such a standard, or accepted practice? or should I just add the comment "true length" to the dimension?

Thanks,
Dave

-Dave
Everything should be designed as simple as possible, but not simpler.

 

[ctopher]

I h ave seen it different ways.
You can show one view with isometric indicating all dimensions
Or...
You would show your normal views. Additional views would indicate if rotated (CW 45 deg, CCW 30 deg, etc) from a view.
More info:

http://www.tube-bending-service.com/pdf/tube-design.pdf

Or...
Show an Iso view and include a bend table (X,Y,Z) coordinates.

Chris
SolidWorks/PDMWorks 08 3.1
AutoCAD 06/08
ctopher's home (updated Jul 02, 2008)

 

[Dave K]

Thanks, that pdf is pretty handy.

-Dave
Everything should be designed as simple as possible, but not simpler.

 

[fcsuper]

I'm not sure the word "True" is appropriate. On a drawing, True is the default for projection ortho or aux views and should not be stated as "true" (redundant). For pictorial views (such as iso's), a statement of "true" added to a drawing means that the entities being dimensioned are not true depictions in that view.



Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group

 

[MadMango]

I've only seen "TRUE" used for radii or diameters.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the be

 

[ewh]

I've seen and used "TRUE" on orthographic views where the feature being dimensioned is not in the viewing plane, usually holes and radii. Granted, this is not best practice, but avoids defining odd view projections for the sake of one or two dimensions, and is supported for radii in Y14.5-1994, para 1.8.2.3. I'm not sure it's kosher for length dimensions.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[Dave K]

Well, I decided that since the views are in the viewing plane, I'd leave off the "true length".

Thanks for the input.

-Dave

-Dave
Everything should be designed as simple as possible, but not simpler.