How can I make a nurbs surface have a thickness?

[MikeB]

I can't figure this out, mabye its not possible.

I have created a nurbs surface. It started as a rectangle converted to nurbs, changed the U degree to 3 and the V degree to 3 and then moved the handles on the interior of the nurbs surface to make an undulating plan, but the 4 sides of the plan still have the same z value.

Then I split the surface at an angle so I have 3 sides with the same z value, and one undulating side.

Ok, now I want to make this nurbs surface have a thickness, here's what I've tried

It wont simply "Extrude"

I duplicated the surface and moved the duplicate down 6" then I tried a "Add Solid", It does become a solid addition, but there are no sides.

Using the solid addition, I tried to "Create Planar Caps". I get the message "Planar caps could not be created in the selected object(s)". (I also tried this with the 2 nurbs surfaces before I "Add Solids" - no go)

Then I tried the "Extract Curve Tool". I extracted the undulating curve from one side of the surface for the top and bottom of the plane I'm trying to create, then i capped the ends using a line segment I converted to a nurb and tried the "Create Surface from Curves" command, no go.

I tried the " Shell" tool - no go

I tried the "loft" tool but it uses nurbs curves not nurbs surfaces.

Any other Ideas, or am I overlooking something obvious. I've not used nurbs before so I'm a little lost.

Thanks

[MikeB]

Never mind, I got it

I had to Extract the Curve for the top and bottom of each side, and then use the loft tool to creat a surface. If you only have 2 curves selected when you use the loft tool it will create a plane.

Still, does anyone know an easier way?

[Biplab]

What you are referring to is "thickening" of a surface. We have plans for this command in the future. There is a roundabout way to do this however. You can create a copy and move the copy of the surface in a specified direction. Then join the corresponding ends by drawing NURBS curves. Now extract boundary curves of the surfaces and create Surface from curves from boundary curves and curves joining the ends. Add the surfaces thus created with the original surfaces using Add Solid.

Yet another way is this. Create a block such that the surface intersects the block completely i.e. the surface extends beyond the extent of the block. Create a copy of the surface and move it in the specified thickness direction. Now section the block with the two surfaces one after the other keeping the proper side (using Reverse section side from the OI palette). You should be able to get a thickened surface.