Summary

A simple leadscrew operated linear slide based on the parts from another thing. Also includes a pair of motor mounts for "salvaged" cordless drill motors

Instructions

This is a bit rough and ready, but I built it to demonstrate leadscrew vs. belt driven linear stages

Most of the bits you'll need come from http://www.thingiverse.com/thing:41897

Build the bits as described and then hack/modify in line with the pictures......

Other parts you'll need
M8 rod (length to suit)
M8 nuts (I used 6 but this also includes 2 for the timing gear mount)
M8 washers
M6 bolts/nuts/washers
Timing gears (I used 20 tooth t2.5x6)
Timing belt (length to suit your motor)
Timing belt tracking bracket (but this was only because the timing gears had no flanges on)
Motor mounts (i've included mine for you to adapt as you need)
Gearmotor (I salvaged mine from a cordless drill)
Lead screw nut (in other words, a small lump of plastic with an M8 thread though it)

If you cut out the motor mounts using a router (as I did) then you'll need to laminate the LH and RH bits together. Those who can print may get away with doing the assembly as a single piece.

Prototype and play....

Linear Slide- leadscrew version