Small depthing tool with custom box used by watchmakers and watch repairers to layout gear trainsSmall depthing tool with custom box used by watchmakers and watch repairers to layout gear trains. May also be used for very small clocks. The tool consists of a small brass hinge which is opened and closed using the thumbscrew at the base. Steel runners with cupped ends are used to hold the axles onto which gears are mounted. By adjusting the lower thumbscrew, the precise distance between the gear axles can be determined. The pointed ends of the steel runners then can then be used to scribe an arc onto the watch plate. The hinge is kept closed with a large flat steel spring. The tool comes with a custom made box with metal hinges and hooks. The interior is lined with a green velvet-like material. The depthing tool may be French or Swiss, but it is unsigned so it is impossible to tell. I do not know how old it is, but certainly is an antique. It may be from the late 19th Century. The brass body measures 3 inches long by 1.5 inches high. The steel runners are 1.5 inches in length. A quarter is shown for scale. Finely made. A must-have tool for the serious horologist, watch repairer, or tool collector. Please view the photographs carefully and ask questions. I will do my best to answer. Thanks for looking and good luck offerding!

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