extracting surface curves, edge loops.

[Tristan]

http://tman.uc.org/tman/pwrCmpSktch.jpg

Ok, so I am trying to extract the curve using power comp sketch from the image i've attached to ulimately move and rescale the resulting curve into a curve i can create the back of the phone, then blend/sweep it back to the main part.

When I use Pwr_CmpSkt right off the bat i noticed 2 things:
1) In the operators there are 3 subojects listed, 2 edges (as i would expect) and a 3rd derived surface.

2) There's a tangency controller, which if i set to no tangency in the Tangency Parameters goes away, but the surface is still present in the operators tab.

Do I have to sketch a new curve entirely to do what I'm trying to do? I would have liked to keep the control points consistent between the main part and back of the model which is why I'm using this approach.

When I flatten the comp sketch into an editable nurb, and then flatten the control points in y space to make it planar, the Pwr_Planar command doesn't work.

Seems like I'm running into wall after wall. Any suggestions/help would be greatly appreciated!

[PiXeL_MoNKeY]

Tristan, you may want to look at the phone file I posted a while back for TheNewOne, here (http://www.npowersoftware.com/forums/showpost.php?p=3693&postcount=5). I approached it from a Solids modeling approach and used blends to create the large fillets/chamfers. You could probably use the same approach for your phone.

1) Extrude the top profile.
2) Create a sketch extrude for the top and bottom faces.
3) Use Pwr_FaceEdit to change the shape of the top and bottom faces with the extruded curve profiles you made.

About your Pwr_Planar problem, try joining the curves in Cmp_Sketch, or convert to a Edit_Skt and join the edges there. Also run Fix Curve and Merge any Verts in the Vertex SO mode.

Hope that helps some,
-Eric

[Tristan]

Hiya Eric, first off thanks for the reply, I really appreciate the assistance. Unfortunately, I still can't seem to produce a planar surface from the extracted edge loop of the trimmed back extruded surface.

I've converted the composite sketch curve into an edit sketch, gone to the vertex sub object mode and clicked the fix curves. The vertices all appear green so there's no errors (i think). When I flatten the edit sketch curve using the scale in the y axis and choose planar surface it still doesn't show me any resulting surfaces, however if you look at the attachement you can see that it did produce something as there are now 2 curves one slightly offset from the other?

I realize I could approach this using a solid solution as you've described earlier, but I think it's really important for me to be able to do this, as it's something I've done in the past in Rhino and prefer that method of modelling when using nurbs.

Filleting sometimes doesn't yield the degree of control I can get from doing rails/sweeps. Have a look at the files if you can get a moment to do so to show me what I'm doing wrong.

Thanks!

[PiXeL_MoNKeY]

The problem is your verts are at different Z positions, in relation to the original creation orientation. This is evident by selecting verts and verifying their Z Coord. You will see they are different. The fast and easy way to make them planar is (Set the timeline to frame 2):

1) Go to the EditSkt select all verts.
2) In the Edit Vertices > Z Coord:
3) Hit the down arrow.
4) Hit the up arrow. (or vice versa)

This will make all the vertices planar in Z Coord and your Planar object should show up. The reason I hit moved them in both directions is the first one offsets the verts (and makes them planar) and the second one centers them around the original selection center.

The fast way to get planar edges, that you know are good is to trim the object with a plane surface (choose the proper trim direction).

Hope that helps,
-Eric

[Tristan]

Nice, thanks a bunch eric!