surface cut

[jeffyoung90]

Alright so I am trying to recreate a naca inlet on a curved surface. The inlet surface has been created underneath the surface using a surface loft, but I have not been able to remove the intersecting surface to make the inlet scoop open. I have tried a surface trim using the lofted surface to trim the objects surface, but the surface above the inlet will not be removed. I have also tried to do a surface cut using the loft but for whatever reason I am unable to select the lofted body. Please help.

 

[MartinShane]

Able to post the file? Or a picture at least?

 

[CorBlimeyLimey]

Does the "cutting" surface fully extend beyond the surface to be cut?
Can you project Split Lines onto the surface, and then Delete Face?

 

[jeffyoung90]

I cannot post a picture as this is covered in an NDA but the projected split lines did the trick. I was able to select and delete the face once the split lines had been projected onto the surface. Thanks.

 

[jeffyoung90]

I'm not exactly certain why but I was able to delete the faces, but they are actually still there. Again, I cannot post a picture but delete face did not really seem to do anything. I cannot select the face again however, but it is still there. I know that's pretty vague but any suggestions are welcome.

 

[MartinShane]

So are the faces you attempted to delete still visible?

If so, what made you think that it had worked initially?
If not, what makes you think the surface is still there?

Just thoughts that come to mind, maybe all too obvious -
Did you accidentally turn on "delete and patch" ?

could you use "extend surface" on the original trimming surface to make sure the surface intersect completely and use the trim tool? (As CBL asked: Does the "cutting" surface fully extend beyond the surface to be cut?)

Do you have any unintentional seams or gaps across the face you are trying to split / trim away that could be leaving sliver faces that are hard to see?

 

[jeffyoung90]

MartinShane, yes the faces are still visible. Immediately after I had done the face delete, the faces were not visible and I could see the objects underneath. I'm not really sure what triggered the faces being filled back in but now the surface is completely filled and the face that I had split and deleted can no longer be selected. When I click on the face I can only select the bodies underneath, so I'm not really sure what is going on. When I deleted the face I did not patch or fill. I did originally use the trim tool to remove these faces, but the same thing was happening so I thought maybe the trim was not working. What I had done was lofted a surface (half a cone) up to an already existing surface using a projected curve on the surface as my guide curve, and I am now trying to delete the face that is over the cone so that all I see is the loft.

 

[rollupswx]

trying to recreate a naca inlet on a curved surface

This sounds pretty generic.
Certainly you can create a simple example that exhibits all the behavior of your proprietary work and attach the file here?
Delete Face does not sound like the best way to me.
Make sure the surface fully cuts the solid (might have to extend).
Several other ways as well.
If you can't post an example then I'm sure someone else will do the work and attach one here, but that often turns into a game of 20 questions if the first solution doesn't match your particular situation.

 

[jeffyoung90]

I will create a simple example and post the file shortly.

 

[rollupswx]

What version of SWx are you using?

 

[jeffyoung90]

Attached is an example of what I'm trying to do. I'm using 2012 x64 SP04.

 

[jeffyoung90]

The problem I am seeing doesn't seem to happen in the part I attached. The part I'm working in is part of an assembly and when I change the transparency of the assembly, thats when the surfaces seem to fill themselves back in. Like I said, I can't select the deleted faces anymore, but I can't tell if they're actually deleted or not.

 

[MartinShane]

Looks straight forward enough.
If the original file was done the same way, it wouldn't trim cleanly since the "duct" surface does not pass completely through the surface it needs to trim.
I would think that a projected split line and delete face would work (seems to have worked OK in this case) even if it is not the most elegant solution.

If I were in your position, I guess I would rule out a modeling issue by trying to trim the surface by modifying the bounds of the 2nd loft to be "above" the target surface, rather than using projected curves. Then close off the front of the duct with a planar surface and knit it to your second loft. You would end up with something similar to the picture I attached, and if there are no gaps the trim should work fine.

If that didnt work, or if you end up with a ghosted surface again I'd start looking for systemic causes (Graphics card driver, yada yada). Have you tried opening the file on another machine to see if offending surface still appears?

 

[MartinShane]

Saw your new post just after posting mine....
Sounds suspiciously like a rendering issue.

 

[CorBlimeyLimey]

The problem I am seeing doesn't seem to happen in the part I attached. The part I'm working in is part of an assembly and when I change the transparency of the assembly, thats when the surfaces seem to fill themselves back in. Like I said, I can't select the deleted faces anymore, but I can't tell if they're actually deleted or not.

Open the part and inspect whether the face is deleted or not.
- Try selecting the deleted face ... are the internal faces selected?
- Try thickening the part ... see if there are edges.
- Try creating a section opposite the deleted face ... see if there is an opening.

 

[rollupswx]

3DSketch3 doesn't match the curvature of the other surface.
And often it is best to model the surfaces to a larger boundary rather than to try to model to an exact intersection boundary and then trim back to get the best intersection. I would expect to see problems modeling as you have done.