'Extrude solid' producing a surface.

[MathU41]

I'm working on a project to have 3D printed. My first real attempt at 3D drafting and I've left off the 2D for a few years, so bare with me.

Using AutoCAD 2015. I have this cross shape, hit Extrude, select Mode, Solid, I select everything, specify a distance, and get an outter surface.

 

 

I can highlight the inner lines, too, and it will do the same thing to the triangles, but form the circle into a solid cylinder.

 

What am I doing wrong?

[BIGAL]

A cylinder has an inside & outside radius ie two circles. press pull ?

[MathU41]

Finally got it. Tried using the press-pull, and eventually had to erase all my fillets and reapply them. Looks like they had a tendency to disconnect when I moved things.

[ReMark]

Extrude a line and you get a surface. Extrude a closed polyline and you get a solid. Extrude a circle and you get a solid. Use PressPull on a profile comprised of lines, arcs, splines and/or polylines or any combination of the four and you'll get a solid.

[JD Mather]

Nobody mentioned it - but there is something wrong with your original profile.

If you had attached your dwg file here - someone would have found the problem for you.

[MathU41]

Thanks for clearing some stuff up, guys. Like I said, my first crack at 3D drawing. Once I got that down, I finished up the drawing.

It will need adjustments before I have it 3D printed, but it turned out perfectly as a demonstration. The prototype will be hand-fitted anyway.

Mr. Mather, I had no idea I could upload the .dwg's here! I'll do that in the future, thanks!