Abstract: A device for quickly and accurately determining the depth of cuts in a key, and for other depth determinations associated therewith. This device has a fixed anvil member having a flat top surface, as a reference surface, with a transverse slot to accept a second edge of doubly-cut key. A tip member having a selected configuration is biased toward this reference or "zero position" surface. Deviation of the tip member away from this reference surface is displayed in a visual manner on a dial indicator, a digital readout indicator or the like. The dimensioning of all the cuts of a key can be performed in seconds to accuracies of about 0.0005 inch. The cuts to be dimensioned can be in edges of the key or in flat side surfaces. Also, the pins of a lock tumbler can also be dimensioned with the embodiments of the invention.

Abstract: A system for testing key duplicating machines to determine the accuracy thereof. This system is provided with a pair of identical detector plates each of which are intended for alignment positioning of the key and key blank within the two vises of the key duplicating machine. Portions of the detector plates which are to be in contact with the vises are provided with an insulating surface, and portions of the remainder of the detector plates are electrically conductive and are exposed for contact. An electrical circuit is provided which attaches to these detector plates such that electrical continuity can be determined visually when the guide member of the key duplicating machine contacts the detector plate held in the appropriate vise.