Blechbearbeitung - Umform Übung Teil 1

To learn the fundamentals of metal forming, we use a model of a classic car, on which the individual parts are recreated to practice different techniques. To ensure an accurate replication of the shape, a template of the part is first taken from the model. As with the real vehicle, this can be done using strips of adhesive tape. The tape is pulled over the individual ribs of the model. The template is then stabilized with duct tape. Once removed and trimmed, the template serves as a guide for cutting the metal. Individual templates made from aluminum strips represent the surface cross-section. In the first step, the rear edge is rounded on a T-anvil. The entire shape is slightly curved. To achieve this curvature, the sheet metal is shaped on a sandbag using a blunt polishing hammer. By placing the sheet metal on the model for testing, it can be determined whether the fit is approximately correct. Any distortion in the sheet metal can be removed by pressing the individual sides out of the metal. The resulting unevenness is smoothed out in the next step. On a hand anvil whose shape precisely matches the curve of the sheet metal, the sheet is flattened with a planishing hammer. This is done with gentle blows that lightly graze the metal. To avoid blows that are too hard, the index finger is placed on the handle of the hammer. The polished surfaces of the anvil and hammer ensure a smooth planishing result. The hammer must not be tilted to prevent damage to the sheet metal from the hammer edge. The shape of the sheet metal can be checked with the formwork template. The template must fit snugly against the sheet metal. Any gaps where the template is loose require further planing of the sheet metal. The sheet metal is then again placed against the formwork template. Afterward, it is smoothed once more with the planishing hammer. The sheet metal is periodically held against the form. Once the shape is correct, the sheet metal is finally smoothed with a planishing spoon. This removes any remaining hammer marks. The sheet metal has been shaped. The next step is to finish the surface.