12mm Linear Rail Alignment tool

Simple alignment tool for centering 12mm linear rail on to 20mm extrusion. Created to aid assembly of linear rails on my new Kossel XXL.

Update - 31/12/2017

Thanks to dream4magi, for pointing out dimensions were not quite right!

Due to inaccuracies in the original tool, I have recreated with the correct dimensions.
The dimensions and the freecad file are included if you choose to modify.

Printed this in ABS with 0.6mm nozzle at 0.2mm layer height, 2 walls and 25% infill
and scaled to 100.5% in Cura when printing to ensure the fit wasn't too tight as no tolerance was allowed for in the dimensions. (just my prefence)