Help create a variety of different products.
Makes plaster relief-map models from which molds are prepared to produce duplicate scale models of land forms: Mixes plaster, water, and retarder in container. Punches holes in map’s surface, using stippler or scorer so that plaster will adhere. Pours plaster over sea-level contour map, and spreads it evenly over surface with brush or spatula. Covers drainage, river, and city lines with transparent media or leaves border without plaster to preserve lines. Builds mound or elevation of plaster around spot elevation pins, leaving pinhead exposed. Observes printed lines indicating contour planes, and consults reference map to ascertain number, elevations, and shapes of contours to be built up with plaster. Pours and spreads plaster on contour planes of successively higher elevations. Fills with plaster angles formed by contour planes at two successive elevations to achieve natural and realistic surface appearance. Removes excess plaster and smooths surface of model with file and sandpaper.