Perfection Planetary Peg Set for Cello 12mm

The Perfection Peg is a deceptively simple mechanism with a size, shape and overall appearance closely matching a conventional ebony peg. The patented design enables easy, accurate and stable tuning of a cello without the use of tailpiece-mounted string adjusters. In basic terms, they employ gears-small, precise, incredibly strong helical gears. Rather than whole-peg rotation and wood-on-wood friction, operation of the internally housed gearing brings each string to its desired tension, and holds it securely in place. Stated a bit more technically, a player, rotating the head of the peg, is actually turning the main gear (called the sun gear). The sun gear drives smaller gears (called planet gears), which "orbit" between the sun gear and a toothed outer housing (called a ring gear). As the orbiting planet gears are spun about the sun gear, they force the rotation of an elongated housing (called a carrier), which serves as the shaft portion of the peg. The gears are also designed so that the shaft rotates once for every four turns of the peg's head (called a four-to-one gear reduction). That allows the Perfection Peg to also function as a fine tuner. The working gears are made from 8650 thru-hardened steel alloy. This same alloy is commonly used for the shafts that drive the propeller blades on helicopters. The ring gear assembly for the cello peg is brass, while for the violin it is aircraft grade aluminum. The carrier/peg shaft assembly is also aluminum. All of the internal parts are permanently lubricated with an ultra-viscous lubricant named 767A Nyogel, the same thing used in various sealed microscope, telescope and binocular gear assemblies. The head is molded from a high-tech plastic called PBT/ABS and the opposite end of the shaft is Delrin, both extremely durable materials.