A rapid engraving process.

This report covers an unconventional means of engraving. The objective was to eliminate the powdering process. Powdering accounts for most of the time involved in the etching process. Eliminating the necessity of powdering would greatly shorten the time required to etch a plate. This process will etch a 65-line screen to a depth of 0.005 in less than 10 minutes. The engraving metal used in this process is copper plated zinc. The copper is stripped from the open areas to give a copper relief plate. The exposed zinc is spray etched with a copper sulphate solution and the sides of the relief are automatically powdered by galvanic precipitation from the etchant. This process is still in a laboratory curiosity stage. Refinements are necessary before it can be considered practical.