Model Tolerance

[euao]

My models reach me with a tolerance of 0.0254 model.
I open it and change the tolerance 0.001.
But I have the feeling that NX does nothing.

I change the menu Preferences / Model.

Is correct?

Thanks in advance

Euao

 

[JohnRBaker]

First MY question, WHY ARE YOU CHANGING THE TOLERANCE TO 0.001mm? Do you design watches or something? Even with the recent (NX 9.0) changes, where we've tightened the default out-of-the-box distance tolerance from 0.0254mm to 0.01mm (0.001in to 0.0004in), you're still going another order-of-magnitude smaller. What is it that you expect that this will do?

As for YOUR question, yes, changing the value of the 'Distance Tolerance' in Modeling Preferences will have NO effect whatsoever on the model or any of it's features. All this does is change the value which will be used when you create the NEXT feature which references the Modeling Distance Tolerance. If you wish to change the tolerances used by any of the existing features, you'll have to explicitly change that value by editing the feature (note that only a limited number of features retain as an editable value the tolerances used when that feature was first created).

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[euao]

Hi John,

You are right. Sure 0.01 is enough.

How Can I Edit a feature?

I´m loading a CATIA model but and I need improve the tolerance model fron 0.0254 to 0.01.

Thanks in advance

euao

 

[JohnRBaker]

There is no easy way to edit an entire part file, that is all of the relevant features, from one modeling tolerance to another. As I stated above, editing the Distance Tolerance in Modeling Preferences will only have an effect on the features that are created after the change is made, but will have no impact on existing features.

That being said, I understand that GTAC has a utility that can be used to update the tolerance of existing features, so please contact them for help with this.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[Toost]

You are loading Catia model and want to improve the tolerances , - Of the Catia data ?

The imported surface will have a tolerance, but it does not "do anything" since it's not "connected" to any defining data.
i.e IF you create , say , a surface in NX using some curves, the tolerance is the approximation tolerance surface-to-curve, the surface will be created within the tolerance from the curve. If you later change that tolerance of this surface NX will rebuild the surface . An imported surface has no such relation.


Regards,
Tomas