This tool is useful for rotating a miniature to get at all angles when painting it with an air brush or rattle can. It also holds the model away from your fingers to help keep paint off them. Simply attach your model to a painting stick (included) with some adhesive putty or tape, slide the stick into the rotating head, and starting spraying. As you are painting you can rotate the model by rotating the thumb-wheel.

This tool is easy to assemble. Print all the parts, insert the gears, thumb-wheel, and rotator head on the shafts, then glue the cover in place.  You can put a bit of lubricant on the gears to make everything turn smoother. 

This tool works well with these other models that I published; they both hold multiple painting sticks to keep your minis safe while the paint drys. Check them out here and here.