NNP

Dieshell.  A pattern from which a die is cut. Dieshells are usually galvanos (electroforms), hence the "shell" part of the term. Since patterns for making dies can be, in addition to electroforms, also metal foundry casts, or even epoxy molds. Dieshells are always negative, from which the die (also negative) is cut on a pantograph. A die is made from a dieshell; a hub is made from a hubshell (both hub and hubshell must be positive). The dieshell is mounted on the die-engraving pantograph as the pattern to reduce the design and simultaneously cut the die. The dieshell usually is made with about a 1-inch flange around its outer circumference that is necessary to mount it with clamps on the pantograph. See electroforming for how a galvano dieshell is made; see galvano, pantograph, die-engraving pantograph for how it is mounted and employed to cut the die.

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