Comprising a thick aluminium circular table, about 40cm in diameter and finished with scratch resistant black epoxy coating. Raised outer rim of the table has circular scale graduated 0 to 360°× 1°, and marked every 10°. Table mounted on a heavy, stable cast metal tripod base through a metal pipe, with base provided with three leveling screws. Also included are four pulleys in clamp that can be attached anywhere along the rim. A detachable pin, positioned at the center of the to table indicate the balancing for forces through the centering of ring, tied to the strings carrying masses and suspended through the pulleys, around it. Supplied complete with set of strings tied to the rings, center pin and 4 sets of slotted masses with hanger, each set having one hanger 100g and masses 1 each of 10, 20, 50 and 100g