Z-Axis Mount for Aluminium Extrusion Ultimaker-2 Clone

This is a redesigned z-axis mount for the [Ultimaker 2 Aluminum Extrusion 3D printer](http://www.thingiverse.com/thing:811271) by [jasonatepaint](http://www.thingiverse.com/jasonatepaint/about). The goal was to increase hole precision for the 340mm rods, and to redesign the top mount for easier mounting and better strength. I removed the middle section of the top piece, so you'll have to measure when mounting.

The mount is designed for 12 mm x 340 mm steel rods. The steel rod holes are EXACTL