modeling - Simple 3D Drawings

I'm hoping someone can point me in the direction of a 3D modelling program or some such.

I simply wish to draw/view: edges/lines; solid triangles; wireframe boxes. I also prefer to manually adjust individual vertices.

Everything I've found seems focused on high quality models or engineering and design. This is understandable but I can't find simple access to the features I require.

This is to help visualize a project I'm working on.

Answer

For questioners asking simple 3D freeware, I have several times recommended DesignSpark Mechanical. It's a bare bone simplification of SpaceClaim Engineer, but still has a remarkable value. Here are three different views of a random drawing that I made in one minute:

And here is another made for removing all suspects of the incorrectness of a simple manual drawing:

Like the free versions of commercial high cost software usually, there are plenty of planned limitations. Some of them:

• There's no other 2D output than screenshots or printing. Fortunately there's some usable exports( see NOTE1).


• Assembling prepared parts exactly with snaps is prohibited

NOTE1: Exporting as several widely used polygon meshes is possible. Printing the current view with Adobe PDF gives a PDF which is an Illustrator compatible vector drawing - change only *.pdf to *.ai in the Windows file explorer. The last omission in the freeware invalidization process rises the value of the software so much that it must be considered to be an error. I didn't even believe its existence until I one day accidentally opened a wrong PDF in Ai and saw it editable.