USB microscope stand

This is a remix of this model: https://www.thingiverse.com/thing:2525155

Differences:
1. The rack is increased in height (by a third).
2. 6 upper teeth were removed.
3. The holder reinforced in the walls and fixing points.
3. The shape of the knobs has been changed.
4. The gear is integrated into the left knob.
5. Washers have been added to remove the transverse backlash of the axis
6. The shape of the base has been changed.


Otherwise, the model is printed and assembled in the same way as the original...