Shop drawings are essential documents that delineate the parameters and expectations for the final product (Figure 8.2). They can be drafted by hand or executed on the computer and serve as a transitional phase between design and fabrication. Usually plotted or drafted at full scale, shop drawings delineate exactly how something will be made and the precise dimensions, material, and finish of the components.
A material takeoff list determines the quantity of material needed to fabricate the design. To do this accurately, it is helpful to sketch the required cut dimensions on scaled drawings of the available stock material. As a rule, depending on the species of wood, purchase 30 percent more wood than is considered necessary to complete the work. For materials with consistent properties such as glass, plastic, and metal, the overage can be as low as 10 percent.
Figure 8.2 Shop drawing of the Dining chair, designed by Hans J. Wegner (1965), fabricated by Johannes Hansen using steel, maple, wenge, and leather. Photography courtesy of Erik Skoven.