Cello Pegs - Perfection Set Geared Pegs - 15mm ABS (Formerly called Planetary)

Construction

Shape, weight & taper
Perfection pegs have a standard taper and fit in the same holes as standard wooden friction pegs. They have the same shape, weight and taper as a set of good ebony pegs. Please note that these pegs still need to be professionally fitted by a Luthier, in the same way a standard peg does.

Heads
The head of a Perfection peg is made either of ebony, rosewood, or ABS synthetic (the plastic often used in car bodies). The head is attached to the central sun gear, which runs down the center of the shaft.

Shank
The section just below the head is the shank. Made of aircraft-grade aluminium, turned, polished and anodized, the shank encloses the the gears. When the peg is installed the shank is fixed in the peg box and remains stationary.

Planetary gears
Inside the shank is a set of planetary gears, and the brake which holds the gears in position against the tension of the strings. The 4:1 geared reduction provides accuracy and control in tuning. The gears themselves are made of toughened high-tensile steel, they are immensely strong, permanently sealed and lubricated and never require maintenance.
Shaft
The shaft is the section with the string-hole. It sits below the shank and is made of anodised aluminium and Delrin industrial nylon. The shaft is driven by the gears and turns once with every four turns of the head.
See the Perfection pegs planetary gear diagram.

Operation

Perfection pegs work in much the same way as a conventional peg, but more accurately and reliably. Turning the head of a Perfection peg tunes the string sharp or flat.

When a string is tuned to pitch a variable-friction brake holds the gears in position against the tension of the string. The player controls the degree of friction by exerting a light inward pressure on the peg head as a string is tuned. Friction is increased by pressing the peg head inwards as it is turned, and can be released to let the peg turn more freely by pulling the peg head gently outwards during rotation.

Turn the peg head to change the pitch. Press the head inwards to make the peg more firm and hold the tension. Pull the head outwards to soften the peg action.

To get a feel for the tuning action: back the peg off a couple of turns (so there’s no danger of breaking a string) and work the head backwards and forwards a few times, a half turn each way, as you apply a gentle inward pressure to the head. Now do the same thing while gently pulling outwards on the head. You will quickly discover how to adjust the peg for ease of turning and optimal hold.

If at some stage you find that the string is not holding, gently apply an inward pressure as you turn the head and this will make the action more firm. Or, if the peg becomes difficult to turn, gently pull the peg head away from the peg box as you turn and you will feel the action become easier.