Printing Circuits

From instructables.com:
Given the schematic for a simple circuit, make it a real circuit with the base components, some
conductive thread, and a 3D printer. No solder, no etching chemicals, no
sending away for anything.
This Instructable is to serve as the how-to guide for a 3D-printed
electronic circuit library implemented in OpenSCAD, 3D-PCB.  I recreate
the full replication process of a simple analog circuit of a blinking
LED made from a few transistors, capacitors, and resistors, a single
LED, and a AAA battery. I will review how to import the library, and use
it to place components in OpenSCAD in a grid, and teach you the basic
wrapping techniques for all the included features.