Clock Part Definitions 

If your are having dificulty finding clock parts call us at 908-204-0095. 

 Verge:         also called  anchor, pallet,  or escapement

 Chime:         also called  chimes, gong, melody

 Gong Rod:  also called  chimes, gong, strike

 Main wheel                      also called  great wheel, spring barrell

 Second wheel                   this means the wheel next to the Main wheel. We generally assign numbers to each

                                         wheel, up from the bottom of the gear train, to refer to that wheel.

 Centerpost                       this means the post the minute hand fits on

 Centerpost gear               this means the gear on the centerpost ( sometimes called the 3rd wheel )

 Hour tube                        the sleeve that the hour hand fits on

 Pendulum                         also called  pendulum ball, pendulum bob

 Suspension                       also called the suspension arm. The pendulum is attached to this part. When a user

                                         "puts the pendulum on the clock," this is what it is usually attached to.

 Suspension spring            this means the spring that the suspension hooks to that provides recoil for the

                                         swing of the pendulum

 Suspension post                this means the post that the suspension is hooked to

 Adjusting nut                   this means the nut at the bottom of the pendulum bob that allows for timekeeping

                                         adjustments. (The adjusting nut is not always at the bottom of the pendulum.)

 Strike                               The sound the clock makes when it counts the hour. Do not confuse this with the


 Ratchet wheel                  Part of the mainspring ratchet assembly. The ratchet wheel is a gear, with a square

                                         opening in the center that fits the mainspring arbor precisely. This gear usually

                                         has slanted teeth with valleys that fit the end of the click (ratchet dog)

                                         precisely, thus keeping the mainspring from releasing and destroying, gears,

                                         person's fingers, and other clock parts. This is the device that holds the

                                         mainspring tight after each turn of the key. When fully wound, this device has the

                                         full power of the mainspring on it. The stored energy ( potential energy ) of the

                                         mainspring is held by the one single active tooth on this wheel in conjunction with

                                         the ratchet dog. Failure at this point causes massive damage. 


Click                                Part of the mainspring ratchet assembly. The click is often called the ratchet dog.


Click spring                     Part of the mainspring ratchet assembly. The click spring causes the click (ratchet

                                         dog) to snap into the valleys of the ratchet wheel.


Maintaining hook            A hook that holds a spring tight inside the main wheel of many weight drive clocks.

                                         This spring applies pressure in a reverse direction to the pull applied by winding.

                                         The reason for this is that when the clock is wound while it is running the power

                                         to the gear train is briefly interrupted which makes the escape wheel stop.

                                         Occasionally the verge will then come down right on top of one of  the teeth of the

                                         escape wheel, causing it to be bent. With the spring and maintaing hook in place

                                         and  functioning correctly, enough pressure is maintained on the escape wheel while

                                         winding the clock to prevent damage by keeping just enough power to the escape wheel

                                         to keep it from stopping.


Isochronal error              A fancy way of saying a mainspring has more power when it is fully wound, than when

                                         it is run down. The power curve of a mainspring is non-linear, thus resulting in

                                         timekeeping errors. ( see the section in trouble shooting more info ).


Fusee ( Fuzee )                 A design by which the power from the mainspring of a clock is delivered to the rest

                                         of the system through a spiral cone shaped spool with grooves for the cable. The

                                         top end of the mainspring power is delivered to the smallest diameter of  the fusee.

                                         This reduces the ampount of power delivered because of the difference in diamters.

                                         The bottom end of the mainspring power is delivered to the largest diameter of the

                                         fusee. This increases the amount of power available with respect to the top end,

                                        thus effectively eliminating the effect of isochronal error by mechanically

                                         equalizing the power delivered by the mainspring.


Platform escapement       Usually found in ships bell clocks, and expensive french carriage clocks. This

                                         usually consists of a balance wheel and associated parts, a verge which is often

                                         jeweled, and an escape wheel. The design of these balance wheels is very similar

                                         to what is found in large pocket watches. Some of the higher quality balance

                                         wheels have timekeeping adjustment screws in the wheel itself.


Sequence                          The sequence of the operation of the gears and / or hammers and / or shutoff and

                                         /or trip levers  of a particular section of a mechanism to produce the correct

                                         result of sound or mechanical operation.


Top end power                 Fully wound mainspring.

Bottom end power           Mimimum mainspring power. Power delivered at the "almost totally unwound state"

                                         of a mainsping's power curve.