Craftsmanship series: Deep drawing
After blanking the different work pieces it’s now time for some metal forming.
A lot of forming is done with presses, where the blank is forced into a die with immense pressure. If the form is too complex, it can be done in multiple stages. Pressing a cup is mostly done using a so-called deep drawer. Because the shape is too “deep” to be pressed on a normal press. Take for example the oil container.
At first a worker places the round blank into the deep drawer. Sensors make sure it cannot be operated to prevent major injuries. When the blank lies secure on top of the die and the hands of the operator don’t trigger the sensors anymore, the machine can be operated. Then the blank holder pushes down to secure the blank in place on the die. Hereafter, the punch presses down on the blank and forces it in the desired form.
Now the cup is born. However, the edge is still rough, because it is nearly impossible to form a cup from a blank in the deep drawer and creating a perfect edge at the same time. Our deep drawer cuts the edge directly after the cup has been formed. This way, cups with a clean, straight edge are created.
Now it is time to close the cup, with either a double hem or a seam, which we will explain in the next craftsmanship post.