Opaque 2D surface

Is there a way to create an opaque 2D surface in Autocad?

I am trying to model a complex cardboard box in 3D. The closest thing I've come up with is the REGION command or exploding an extruded solid and deleting unwanted faces. However, the resulting surface is opaque from only one direction. Is there a way to make it opaque from both directions?

I'm using AutoCAD 2005

It's been awhile but does 2005 have a 3DFace command?

Do you have to use a surface? Could it be a solid?

3D face is also what comes to mind but then again its availability to 2005 is not sure. edgesurf could also do this but you must have a minimum of 4 sides to work with per surface.

Ya!Like to create car model,you must need to surface tools!

3dface,edgesurf,rulesurf will be great!......:)

2005 has a 3dFace command but I can't figure out how to make curves. The command line asks me for points.

are you trying to just make a box you cant see through? why does a solid model not work for you? if you need different levels of opacity you can render using a tinted glass material. do you have a screen shot of what you are working with?

I have decided to redraw the box with solid walls and use that.

It would be really helpful to know if you can cut curves in a 3D face. I could use that to create a 2D label. I have drawn solid labels in the past and they were difficult to place on the box because the label had a thickness.

This is as close as I could get with regions. You can see in the 2nd picture that the open part of the box is transparent.