I am building a poor man’s Computer Controlled Router (Milling Machine). My first step will be to bootstrap the ability to mill needed components. Before I can make my own linear bearings, I am using cheap linear rails from the AS-IS (Surplus, Scratch & Dent) room of IKEA. Specifically, drawer rails make relatively good linear bearings. (Well, relatively good compared to what I could make myself without a mill.)

Shown here is the X table, able to translate in one dimension. The highly precise linear rails and support material (base & X table) are courtesy IKEA’s As-Is room. The stepper motor assembly cost $25 from a surplus supply house.

A 3/32 machine screw holds the servo to the base. Not exactly well secured. I secured the other end slightly better. The entire goal is to build a milling machine as cheaply as possible, and then use it to build a better milling machine.
The video below shows the X-Axis table moving for the first time. My servos and screw drives have a range of almost 6 inches. It takes 46 thousand steps to travel 5.5 inches, or 0.0001″ per step (which is my maximum possible precision). The speed is slow, with 605 steps a second, or 0.072 inches a second.