i3 X Axis Linear Rail System

*While usable, this is still a WIP*

I designed this to replace the 8mm smooth roads on my Hesine m505 with 400mm MGN12 linear rails and 10mm wide belts. This design incorporates a floating X axis idler to help reduce Z wobble artifacts. Currently it is using an old fan duct design and it is also compatible with my Z endstop adjuster.
I will later update this for use with 450mm rails (what I should have ordered), and different pulley sizes.
Note that this is for printers with a spacing of 22mm between lead screw and smooth rod centres.

LM10 version now availiable.
2016/11/15 Now with even more overkill. SFU12 ballscrews and LM10 smooth roads.

BOM;
mk8 extruder idler, spring and supplied M3 bolts.
2x 400mm MGN 12 linear rails and 2x H (long) blocks.
16/20T 5mm bore G2T gear and idler pulley
1X M5x20 bolt + nut
An assortment of M3x 5/10/15/20 TBD + nuts
1X M3x40mm
Small piece of PTFE tube