Pen Mount for 3D Printers ( Incl. Prusa i3 MK2 )

I created this from scratch but it is heavily influenced by Tech2c's pen holder found here: https://www.thingiverse.com/thing:2459624

Features in Thomas Salanderer's video "Making PCBs the RepRap way!": https://www.youtube.com/watch?v=sL0LZFcNaow

Parts required:

* 1x Mount for Prusa i3 MK2 https://www.thingiverse.com/thing:3166868

* 2x LM8UU 8mm Linear ball bearings 8x15x24mm
* 2x 100mm x 8mm Stainless Steel Round Bar
* 1x elastic band. - Hook this around the tab at the bottom and