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Design Tips How
Engraving Works The
Evolution of Engraving Techniques Mezzotint engraving was invented in Germany in 1642. In a mezzotint, the engraver burnishes areas of a plate or die to produce an unlimited gradation of tone. Because this captures the effects of light and shadow so well, early mezzotint engraving was often used to reproduce famous paintings, broadening their audience and appeal. Aquatint engraving, invented by Jean Baptiste Leprince in France, combines etched lines with clearly differentiated tonal areas. The result resembles the flat tints of an ink or wash drawing. Spanish artist Francisco Goya was the acknowledged master of the aquatint technique.
 Engraving:Engraving is a skill-intensive discipline, but modern technological advances have made engraving economical, especially for large runs. In place of hand engraving, several mechanical and photomechanical plate-making options now exist. Three-Dimensional Routing: Utilizes a template and mechanical tracing device called a router, which cuts directly into the metal. The depth of the cut can be adjusted and controlled, making it possible to create "raised" or "sculptured" surfaces. Preparing Artwork: There is no difference between preparing artwork for engraving versus offset printing. The process requires clear, sharp reproduction art: either a crisp actual-size, camera-ready mechanical or black and white line art on disk. Pre-separate complex images on individual transparencies or files, as each color of ink requires a separate pass through the press. back Plate Size: For most automatic presses, the maximum plate size is 5" by 9", while the actual image area on the plate is about 4" by 8". back Specifying Inks For Engraving: Water-based inks are the standard inks of today and create a matte opaque surface impression (with the exception of water-based metallics) and are generally quick drying and laser compatible. back Metallic Specialty Colors: Metallic inks are available in three reflective colors: gold, silver or bronze plus a new array of pastel colors. Caution should be exercised when specifying metallic inks for small, finite type, as the metallic particles used in these inks are not as finely ground as color pigments. A rich surface gloss can be achieved by a second pass through the press to "burnish" the surface of the ink. Burnishing forces the metallic particles to flatten and reflect more light. It can also reveal extremely subtle details within the engraved image. back Specifying Papers for Engraving: Engraved images may be reproduced on virtually any paper, provided the paper is strong enough to accept the pressure of the press. The high-tensile strength of cotton-fiber papers is ideal for engraving. back Compatibility With Other Processes: If more than one printing process is specified, the engraving should be run last. This prevents subsequent processes from flattening previously raised engraved areas. Engraved printing is ideal for use in both laserjet and inkjet printers. back Engraving Envelopes: Since envelopes are not perfectly square and if precise registration is required, consideration should be given to engraving the envelopes on flat-sheet paper and then converting them to envelopes to preserve registration. Consideration should be given to where the reversed image will appear on the back of the envelope in relation to the flap edges. If no image is to appear on the back of the envelope, the flap should be lifted before stamping to avoid debossing on the flap. back Proofing: Prior to engraving the plate, proofs should always be examined to verify that all of the image in the correct color is present. Press proofs are also available, typically for an additional cost.
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