Grandfather clocks are popular long case clocks. The long wooden case contains a pendulum and weights. The pendulum regulates the time, while the weights supply power to a system of internal gears. Case and movement, or gears, are often made by different makers. Find the manufacturer of a grandfather clock by examining both the clock itself and the movement inside.
Look on the dial, or face, of the grandfather clock. In most cases, the name of the manufacturer of the case and dial is painted or engraved on the clock face.
Look for a trademark, or copyright symbol, on the clock dial. In the 19th Century, many non-American grandfather clock manufacturers did not include their names on the piece. Antique Clocks Identification and Price Guide offers pictures of the more common of these marks.
Slide open the hood of the grandfather clock to get a look at the movement inside. The hood is the top of the clock case. Some clocks contain a locking mechanism, or latch, that presents the hood from being opened. Feel around inside the clock and undo the lock if the hood cannot be moved.
Find the nameplate on the movement. Many grandfather clocks contain movements from the Black Forest region of Germany. Common modern makers include Hermle and Keininger. Both, for example, are commonly found inside Howard Miller clocks.
Examine the movement for identifying numbers, if no name is present. Clockworks offers a list of serial numbers that identify specific movements from a variety of grandfather clock movement makers.