Pivots are half the heart of your clock movement. Bushings being the other half (see Bushings). Pivots are the bearing surface of the gears and pinions that turn in the brass plates of your movement. Pivots wear from lack of lubrication and stresses exerted by the mainspring or weights powering the clock. Pivots need to be smooth (polished) and free from dirt to turn smoothly. During an overhaul , we take the pivots and polish them in a jewelers lathe until they are perfectly straight and have a high polished look to them. Pivots can also become damaged when a mainspring breaks. A mainspring breaking can bend or even break off a pivot. Some pivots can be straightened, but usually the better repair is to replace the pivot.