Pipe (Inches)

thingiverse

This is a very versatile module I've been using in OpenSCAD for a long time. You can make pipes or tubes whose diameter can vary from one end to the other if you wish. If you don't want to have a hole running through the center of it, use zero for the inner diameters. If you want it to come to a point like a cone, use zero for one of the outer diameters.