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This patent model demonstrates an invention for an engraving machine with a pantograph; the invention was granted patent number 9743. The machine for "mezzotint or other engraving" stood on a table ...

Smith & Wesson switched to engraved roll marking dies to replace marking dies made by the EDM process to improve the life of its stamping tools and to ensure that the marks it makes on its weapons are ...

William Dahlgren, a self-taught inventor who revolutionized the engraving industry a quarter of a century ago and was recently fiddling with computerized player pianos, died in his San Francisco home ...