3D Poly Extrusion

[lineweight]

hi,

i'm curious, if i have a 3d polygon made (in this case, a rectangle with an angular bend in it), how would one extrude this? Extrude Along Path doesn't like the 1/4" line i try to extrude it along and Shell won't work either. I can think of other ways to complete this command, but in this particular instance, i need this rectangle extruded from this poly.

thanks.

attached is an image capture of the rectangle i am trying to extrude or create a thickness of.

[Gytis]

Convert to Nurbs first, then Shell.

[lineweight]

Hi, thanks for the reply. I have converted the object to nurbs and now have the object selected. However, i cannot shell this thing for the life of me. With this poly (now a nurb) i seem unable to select the face.

Perhaps this has to do with the creation of my object. I set 6 points (3d vertices) and then created the 3d poly out of that, as opposed to creating two 3d polys rectangles that exist on two separate planes and then selecting each face and shelling them separately. Do you think this is the preferred method of performing this function? How would i merge the two individual rectangles after i shell them so that they appear as one cohesive bent panel?

[Pat Stanford]

I tried something similar this morning, but I drew a polygon (open) in top view and then extruded it to get the shape.

After I converted to NURBS, it ended up as a group. Until I ungrouped it, I could not shell it either. Make sure you don't have a group and then you should be able to shift click to select each of the NURBS surfaces and shell them at the same time.

Pat

[lineweight]

Is there a reason you extruded an open poly instead of closed?

Until this is extruded, i don't think it will be a grouped object (it's not one right now).

I think part of my problem may be that it is a poly that exists in orthagonal planes in 3d space. as such, the extrusion will be odd. i think i may just have to build two planes, extrude and go from there. but i was hoping for another method of doing this (in the event that i need to do something similar but more complex in the future).

[Gytis]

My apologies for a too brief response.

Draw a profile (top or bottom of "door"), and a rail (the height) and 3D Modeling>Loft

THEN Shell. Very quick and clean.

I will post an example when I get a moment...

HTH

[lineweight]

Thanks for your response.

So, what i just did was a polygon outline of the peeling skin in plan. I then drew a line of the height of the panel that is peeling back. Then, extrude along the path (height).

Now, what would the difference be between that technique and what your are talking about with lofting and then shelling? Would your technique be particularly better for a curved (nurbs) peel and extrusion/loft?

Thanks again!!

[Pat Stanford]

I extruded an open polygon so that I would only get the two pieces. If you have a closed polygon you will get the top and bottom surfaces and a minimum of three sides (a closed polygon has to be at least a triangle.

I have just found that if you need a flat surface in 3D, it is often easier to draw a line or poly and extrude it.

Pat

[Benson Shaw]

I tried it a couple times. First tryy would not complete the shell until I moved out of plan view. After that, any NURBS would shell in any view. Strange.

But, why poly to NURBS to shells, or lofts and profiles?

The wall tool should work well for this.

Or, use the Dbl Line Polygon tool, choose the Lines and Polygons mode, set the thickness. Draw the plan view shape w/ 3 clicks. The end caps are applied automatically. Then extrude to height.

Or for a curved peel, use the polyline tool to draw one plan view edge, offset for thickness, draw the end caps, compose, extrude.

-B