Depending on the situation sometimes I'd use scale X,Y,Z in Surfcam and flatten out the surfaces or surfaces made from solid faces. You can't scale Z to zero so I'd run Scale X,Y,Z with the X and Y set to 1.0000 and the Z set to .0001 or lower (I don't remember the lowest it will go) and then do it 3 or 4 times. In my experience I had better luck creating splines without gaps this way than trying to project surface edges to a plane (surface in Surfcam). I don't know if doing that in NX helps your cause or not.
Here's my $.02 on transitioning from Surfcam and I'm not saying this is the case with you guys. IMO most programmers that are looking to move on from Surfcam are upset the old Surfcam is no longer around and the new rebranded Surfcam is not like using what they used to use. So they're looking for a replacement for old Surfcam which is pretty much 20 year old technology, old school way of doing things etc. etc.. Much like Disastercam is but with 100 times less bugs. So if you think you're going to run NX with a Surfcam mindset way of doing things you're not going to be happy with NX or any other modern more powerfull software. I cut my teeth on Surfcam and Mastercam (they were darn near identical 20 years ago) and had a tough time retraining my approach to run PowerMILL 2 or 3 years after learning those which is more like NX than it is Disastercam or Surfcam. I wish I never even used them in the first place after getting some seat time with PowerMILL. If I had a garage shop I still wouldn't be afraid to use old Surfcam for drilling, tapping 2 1/2D stuff etc. (it's easy and fast for simple bang it out stuff) but for 3D surfacing or anything else I would rather drive a garbage truck for a living than to be a programmer.
My mistake; I was under the impression you were looking for information on tool path operations...
I received your first reply by e-mail, reply which you then edited.
I was useful thanks.
I remember from my old use of SurfCAM where I used to create a parting line for a model using a draw direction. In surfCAM, you can extract a Silhouette of a 3D model using a command when the model is seen from a direction...usually we orient the model to a view which is normal to draw direction and use that as viewing direction.
In NX, you can 'extract' a silhouette curve using the command shown in image. I guess your CAM person is asking for the same.