The balls are made of standard steel with the usual accuracy. The mechanisms and the gears of the transmission are made as described for Figure 1 and other similar mechanisms. The support frame and body can be made of transparent plastic to look more attractive. A standard clock dial can be installed with the transmission 1/12 between the minutes and hours hands. The base and support frame are made of steel sheet or plastic, laminated fabric, etc. The screw pipe can be made of aluminium or steel sheet or square shaped steel. It can also be made of acrylic resin or transparent PVC.