Abstract: A device for holding wires for measuring screw threads by the three wire method with a micrometer includes a body portion and a plurality of wire holder ears in a vertical position, the wire holding ears being responsive to rotational movement and the wire holder ears being limited in the rotational movement by weighted lower base portions provided on the bottom of the wire holder ears. The wire holders are further limiting in movement by a movement limiting attachment engageable with an anvil of the micrometer, such as in a collar or U-shaped track have a defined recess for limiting the movement of the wire holders within the confines of the recess. To further stabilize the rotating spindle of the micrometer within a bore of the wire holders, the wire holders are further provided with C-shaped spring clamp engageable within a further bore encircling the bore through which the spindle extends.

Abstract: An apparatus for holding wires for measuring screw threads by the three wire method includes a body portion and a plurality of wire holder ears in a vertical position, the wire holding ears being responsive to rotational movement and the wire holder ears being limited in the rotational movement by weighted lower base portions provided on the bottom of the wire holder ears. A ledge is provided for holding the screw in position perpendicular to the orientation of the three wires in a position for the pitch diameter of the screw threads to be measured.