Definizione

• Guide Pin and Bushing.  Tooling devices to aid in the aligning of dies. A matched pair of dies will have a protrusion (guide pin) in one die and a hole (bushing) in the other. In actual practice the tool and diemaker will drill two uniform holes in the proper aligned position and furnish a steel rod which will fit both bushings. These are located on the face of the die outside the die line on, of course, open face dies (such an alignment could not be made on coining or collar dies). When first made the pins fit somewhat loosely in its bushing, after use they tend to  stick in one.
  If two or more guide pins and their corresponding bushings are prepared for one die, they are each a different diameter. Once both dies are aligned by this method, striking may proceed if the guide pin is removed. If it is left in place during a long press run it would, however, preclude the dies from chattering or rotating. (The die containing the guide pin would, of course, have to be placed in the lower, or pile, position in the press so gravity would help hold in place.)  See die alignment, keying, force.

  excerpted with permission from

  An Encyclopedia of Coin and Medal Technology

  For Artists, Makers, Collectors and Curators

  COMPILED AND WRITTEN BY D. WAYNE JOHNSON

  Roger W. Burdette, Editor

Le relazioni