Professor's Rubik's Cube Modification?

The Professor's Rubik's Cube is a 5x5x5 Rubik's Cube, which can be very tricky to manipulate. If all of the sides are not perfectly lined up, it is difficult to maneuver the sides of the cube. There is a way to modify the cube, so that it is more like the 3x3x3 cube, which uses springs and screws I believe. How do you modify the Professor's Cube?