Just printed and assembled mine. This is a very nice design! I modified it to hold the flex shaft instead of the whole rotary tool.
Add 3 M6 nuts and bolts to your shopping list.
The hole on the knob to lower/lift the drill needs to be bigger.
I had to up the infill (30% - 99%)and/or thicken the walls (1.6 mm - 2
mm) on most of these pieces to make them strong enough to withstand tightening the nut and bolts.
I used a 5/16th threaded shaft, metric stuff is hard to find here and not to mention, a little more pricey.
I used a 3/4 inch wood dowel instead of a pipe.
Had to cut many of the M3 screws down to size.