About Faces Fabrication tips for cabinet signs By Bill Dundas, Signs of the Times Magazine Not long after opening their doors for business, vinyl signshop owners discover that internally illuminated, plastic signs represent an important and lucrative segment of the market. In the constant drive to increase production efficiency, some sign builders ignore important factors that directly affect product quality, safety and, ultimately, customer satisfaction. The first error typically made by a novice signmaker is to assume that flat sheets of plastic are suitable for every application. Although flat plastic sheets are less expensive than formed pan faces, soon after installing a new, flat face in a customer's sign, the signshop owner discovers its true cost. Typically, the caller's remark creates stunned silence on the other end of the line, while the signshop owner fumbles for a reasonable explanation.
Wind pressure is one important reason why sign faces are thermoformed into pan shapes.
Another key reason to pan-form sign faces is to allow greater distance between the face's surface and the sign's internal framework and lamps. Many signs with flat face panels are damaged when high winds blow the face inward, breaking the lamps. Another reason to avoid flat faces involves lighting. In this case, a bright outline of each lamp can be seen through the face. Also, a large, flat sheet of plastic assumes a concave shape when resting on its edge inside a sign cabinet, which presents a poor appearance.