Drafting sketch not displaying on section view when back clipping is active

[yeagsman85]

I have a series of section views on a drawing that I'm trying to sketch on. The problem that I'm running into is I'm also using back clipping on the section views. When the back clipping is active, the sketches on 3 of the 4 views are not visible. When back clipping is turned off, the sketches are visible. I'm guessing this has something to do with the distance specified in the back clipping settings and the "plane" that the sketch is drawn on. Has anyone else run into this problem? Any suggestions?

 

[JohnRBaker]

What version of NX are you using? I just tried this using NX 7.5 and even if I set the 'Back Clipping' so that all the 'model' in the view was 'removed', the Sketch I created in that same View remains. Note that I finally managed to get the Back Clipping to effect the sketch, but I had to move it way out in FRONT of where the model would have ended. In other words, the entire view, even if it had not been sectioned, would have been removed by the location of the clipping plane long before it got to where the Sketch appeared to be located. Now I'm not saying that this may not be effected by where the 0,0,0 was on the model (in my test case it was located near the center of the view).

Exactly what were you trying to remove from the view by changing the Back Clipping plane? Did you try toggling OFF the 'Background' option on the View -> Style -> Section tab of the dialog to see if that did what you wanted?

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

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http://www.plmworld.org/p/cm/ld/fid=209

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

 

[yeagsman85]

I'm using NX 7.5. Using the 'Background' option doesn't do what I need for this situation. I'm trying to show a side view of a feature that is surrounded by other, larger features. I'm using the section view to cut out the features in front and the 'Back Clipping' to get rid of the features in the back and leave just the feature I'm interested in. I can't show what I need to by cutting a section through this feature, hence the reason by the 'Background' option doesn't quite work.

As far as the sketch goes, where exactly does NX place the sketch in a section view? Is it on one of the 0,0,0 planes? Also, the back and front clipping options specify a distance. Where is that distance being measured from? Is that also from the 0,0,0 of the part?

 

[JohnRBaker]

OK, here's something that you may wish to try which while it may not change anything, at least you will have a better idea of what IS happening.

After you add the Sketch to the view, but before your start to play with the Clipping Planes, select the view boundary, press MB3 and select the 'Expand' option. Now you can rotate the view around and see exactly what the view contains in 3D, including the spatial relationship of the sketch relative to the rest of the geometry in the view. And while you can't make any changes to the Style of the view while in this mode, you may at least learn if there's a potential for issues if you see that the sketch is NOT located between where you might be thinking of placing the Front and Rear Clipping Planes. As I said, this cures nothing, but it's at least it's another 'tool' that can be used to predict and/or debug your situation.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

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

 

[yeagsman85]

Okay, so I'm running into this same problem again. I've used the "Expand" function to determine that there is an issue in terms of where the sketch is being placed. To give an example, I have a section view that I've created on the X-Z plane so the Y-axis is coming out of the page. I have an object at Y=-10 that I want to display. There is another feature on the same object at Y=-40 that I do not want visible. I also want to sketch within the section view but NX is placing the sketch at Y=-100. Because of this, I cannot use Back Clipping. It will hide the feature that I want to hide but it also clips the sketch. Is there any way to redefine where the sketch is being created (i.e. move it to Y=0)? I've included an image for clarification.