3d printable elevator/lift

The elevator works via a "endless screw". The screw should be attached to a servo motor (or other type if so preferred). The body of the elevator has 4 holes por metal bars to support it and another one to insert the screw.
When the screw is being turned, the elevator is not able to turn sideways due to the metal bars holding it still; the screw is also attached to a still motor; therefore the only option is for the elevator to go up (or down, depending on the direction in which the screw is turning).
The elevator works fine, although it is a bit slow. It is not thought or intended for any purpouse; it was made as an experiment about movable and mechanical 3d prints.