Summary

the straight rods(8mm x 450mm) and the bushings were scrapped from 2 old printers, as well as the "manual transmission" handle, previously rubber rollers that drive the paper... all the screws and bearings on it were re-used from the original cupcake system with exception for 2 linear bearings on the bottom of the extruder platform and the universal adapter that connects the engine to the screwed rod.

Instructions

You will need:

(reused from the original cupcake Z axis system)

1x NEMA17 Stepper motor
5x 608ZZ "Skate Bearings"
1x M8 Threaded Rod (reuse the straightest one)
Several M3 screws and nuts
2x long M8 screws (from the belt tensioning rollers )
6x M8 nuts
14x M8 washers

(sourcing elsewhere)

2x 8mm straight Rods (450mm long)
2x Linear ball bearings 8x15x24 ( http://www.conrad-uk.com/ce/en/product/216992/Linear-ball-bearings-8/1210022&ref=list )
2x 8mm x 10mm brass bushings(internal diameter/external diameter) (i've reused mine from old printers i've scrapped the straight rods from)
1x universal adapter joint (i had this one arround but you have also some already designed here on thingiverse that would do the job just as well, like for ex http://www.thingiverse.com/thing:19179 )

(Printed parts)

All the parts contained in the RAR folder.
(I've printed mine with 0.2 infill and double wall at a .4 layer height and it works great, i've also used a 3 mm diameter enlarger for the screw holes after the parts are printed, that makes it much easy for the screws to fit in)

[notice that some files have a multiplication factor in the end of the filename, that means the number of items you need to print]

Cupcake Zi-Riderr #1