This is a great little CNC design by Vladimir.

UPDATED: 1:56:32 pm GMT 25-Nov 2018
Sorry my bad, i forgot to upload New Y-Axis Plate/Bed. I had to narrow this every so slightly to fit between LH and RH Sides as they are thicker.
See New_Y_Plate_Base_rev01.dxf. There is a layer with the original as well.You will need two of these, one to hold the bearings and the y nut holder and a second copy to create a clamping scuff board to sacrifice.

I have put this re-mix here for a 12.7mm ply / Half Inch Version as i wanted a stronger construction than the Original lean 6mm. The DXF files included here are to make the wood panels for this re-mix. I have simplified both side panels (LH and RH ) to the same cuts but removed the controller mounting holes. The front and back are also the same holes and cuts. The top rear bridge is also modified. All to accommodate a thicker Ply.

There is also an upload here for a new Y-Axis Nut Holder. The original design clashes when you use 3D printed couplers. See cnc_new_y_nut_rev01.scad

Also uploaded a simplified version of Z-Axis nut holder as could not get nut to hold in clamping. Requires supports when printing. See z-nut-holder_exported_extrude_rev01.scad

Also when printing the Lower Tool Holder shows no thread for the Rotary tool but it is there when printed - See comments in the original Design.

For making the X-Axis rail and Y-Rails, i used 10mm alloy bar from DIY store. X and Y need to b 330mm and Z need to be 320mm. For Z-axis i used M8 thread rod L=250cm.
Roll the bar on the ground to make sure its straight before purchase.

I 3D printed all couplers from https://www.thingiverse.com/thing:964680

The controller (see pic ) is from ebay and is a combined CNC and Laser running GRBL v0.8. If you use T8 rods and M8 rods together you can only achieve a double step (x2) over the 400. There is a 30khz pulse limitation. If you use t8 rods all round you can use x16 over the 400.

Note all for assembly on the Z-Axis it is best to buy M3 low profile cap nuts as the Bearing retaining screws get very close to the tool holder.