Abstract: A vice jaw assembly mounted upon a precision machining piece of equipment, the equipment including a platform accessible by a machining tool. The vice assembly includes a base which is fixedly secured upon the platform and first and second spaced apart jaw members which are in turn mounted upon the base. A crank mechanism is employed for actuating at least one of the jaw members in directions towards and away from each other. First and second spacer blocks are secured to the first and second jaw members, respectively, by mounting bolts which extend through aligned apertures between the spacer blocks and jaw members. A mounting pin secures to the first spacer block and extends through an aperture in the second spaced apart spacer block. Additional intermediate and floating spacer blocks are arrayed at predetermined locations between the first and second spacer blocks and each includes an additional aperture formed therethrough which receives in inserting fashion the mounting pin.