All cad files have been updated to the latest and greatest as of 12-31-2019. And yes there will be occasional updates during the build season. The address is
https://workbench.grabcad.com/martin.pirringer-2/models
Project Frame05F is the latest itteration for a frame design still using the toughbox mini for gear boxes and a motor of your choice, Then you have Pulleys (HTD-5 and GT2 master in ipt format to roll your own) and Bearings and then some prototypes that are off season and mostly have been tested and reported here like rack2020 and frame2020 and elevator and then the electronics folder and some others. to tune in.
All gears have been designed with a backlash of .2mm total which is to allow for an overprint of <.1mm in any direction so keep that in mind when you dial in your extrusion. That means the 2.0mm thickness wall W should come out 2<W<2.1 mm measured at any point to make good gears and bearings. On other frame parts its not that critical
When you mount the toughbox minis on the 3dP holders/axle mounts (currently only for 6 in wheels tank, omni and meccanum tested) either use the steel plate that came with the toughbox minis or wrap it in glass - recommended 3-4 layers of 6 oz. Cloth with Polyethylene resin. Either way print it solid - that means enough perimeters to have no need for infill and no air left.
The min thickness in the Frame05f is 5mm the max thickness is 8mm So that means you should set your slicers perimeters to a minimum of whatever comes out to 4mm and a layer height of 50% nozzle width so for a .8 nozzle that is .4mm layer height (.2 for a .4 etc). If your printer uses a leadscreew for Z (most do) set the layer height also to a multiple of .04mm Layer width for outside perimeters 110-120% nozzle width and other layers 120-175% nozzle width. then calc the perimeters to make at least 4 mm
Example. .8 nozzle outside .88 other perimeters 1.2 - means use at least 4 perimeters.
Read the tutorials on the grabcad site as to how to set the proper speed or set the volumetric max E if your slicer can handle it (only one I know that can is prusa slicer)