This remix is simply providing all of the aluminium plates as STL files for 3D printing, rather than having to buy or mill the aluminium parts. I've 'tuned' the parts to provide as much rigidity as possible whilst still maintaining dimensional accuracy by recessing the screw holes to the original depth. The original project and documentation can be found here: https://www.thingiverse.com/thing:1684109
This CNC machine looks to be the most stable I can find on Thingiverse and OpenBuilds. It's got some very detailed supporting documentation. Someone else has built it by printing the parts in ABS and has reportedly had decent results: http://www.openbuilds.com/builds/ooznest-ox-with-3d-printed-gantry-plates.4478/
Their recommendation was to extrude the 3mm aluminium parts at 6mm in ABS so I've taken it a little further and made all parts 8mm thick to ensure they're strong and rigid enough. I haven't build this yet, so I'm not sure if making these parts 8mm thick will affect dimensional accuracy during the build. I'm just sharing the extruded DXF files for anyone who's looking for them.
Note: the _Xx denotes how many of this part you'll need to print. eg. Y-BRACE_X2.stl means you need to print 2 of these parts.
Edit 24/05/2017: Based on advice from the OpenBuild forums, I've made the plates thicker at 10mm and recessed the screw holes to a 6mm thickness.
Only use ABS or PETG for these parts and 75-90% infill.