So what is the OOTB NX11 modeling tolerance?
I ask, because yesterday the machine shop showed me an issue they have when exporting parasolid from NX and importing to Edgecam. The model tolerance on the extrude was .001, and I thought the default was .0001. Today I fired up OOTB NX11, and it looks like it's .0004.
I want to use the recomended Siemens setting, so is it .0004?
I should have noted, we model in inch units, which would be .0004 when converted.
The default modeling tolerance in NX 11 is .01mm or .0004 inch. The default should be good for most "normal" sized objects. If you deal with really large structures or really small, precision parts, you may need to adjust the value up or down respectively. A rule of thumb that I heard a while back is to set the modeling tolerance ~1 magnitude smaller than the smallest tolerance value that you expect to use.
Note that tolerances on individual features can be set independently of the global modeling tolerance. Also, if you are using a template, the parts will inherit the template settings which may differ from the value in the customer defaults.
After more investigating, I discovered the following... we have two seed files, one for model, and one for assembly. They were setup before I got here, so I don't know the history, but the modeling tolerance in the model seed was .0004, and .001 in the assembly seed. That, is how I think the difference in why some files had issues, and others did not. Why we have two seeds, and why a user would start with the assembly, to create a model, I do not know.
It sounds like the two seed parts were created using different historical versions of NX, the Modeling template using a more recent version of NX, after the change in the default modeling tolerance which took place in NX 9.0, and the Assembly template, which most likely was created using an older version of NX, prior to NX 9.0.
Note that I posted at the time of the release of NX 9.0 a rather extensive explanation of the changes and the rational behind them in the 'Eng-Tips' forum:
I hope this helps explain what happened with the OOTB Modeling tolerances and why.
That would make sense, Both would probably have been done in NX8.5 originally. When I started, I moved everything to NX9, and never thought twice about the assy seed, since it really didn't offer anything that the model seed didn't do.
I suspect who ever set it up originally, was thinking there was a differenc between an assy file, and a model file, since they were migrating from a different software.