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Profilr surface tolerance for not oriented slot

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filippoGDeT

Automotive
Aug 20, 2015
17
Dear Guys,

Hello to everbody who read my post.
I need to understand if the use of profile tolerance fully define the shape and orientation of this slot as per attached picture.
If not you think that I need to add basic dimensions? I'm in trouble to define basic dimensions to these datums as the slot is not oriented as them.
I hope somebody has some suggestions.

Thank you very much in advance.

Filippo
 
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The profile callout itself (the feature control frame) is fine. But yes, you somehow need to define the relationship of that slot back to the two datums. These days many prints will have a note saying that the CAD model is to be used, and then no basic dimensions would be needed. But on a traditional print, yes you would need basic dimensions to define the length/height of the slot itself, and also the distances back to the datums.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
 
The good thing about basic dimensions is that they are exact theoretical dimensions.

They, for example, are not subject to tolerance accumulation, so you can use as many as you want, as long as eventually you connect your feature to datum.


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

 
 http://files.engineering.com/getfile.aspx?folder=849fb8ff-b304-4808-b293-f11cd73f7f2d&file=Draw2.JPG
Dear Both,

Many thanks for your very quick reply!
Now the situation is more clear. So I will proceed to add basic dimension for locate the tollerance zone to the basic datum as stated in the feature control frame.
In case the shape of the slot will become very complex, as instance an irregular profile very difficult to locate with dimensions do you think I need to made reference to cad model?
Do you think it works well for both ASME and ISO standard?

Keep in touch! Thanks!

Filippo
 
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