TABLE OF CONTENTS The importance of an accurate flat layout has been stressed throughout the preceding text. In die work and any sheet-metal work in general, the importance of an accurate and dimensionally correct flat layout cannot be overemphasized. Many problems may be avoided if a full-sized or scaled layout is made first and the part s manufacture is evaluated on the basis of it, instead of referring to the bent-up drawing, which, after all, may or may not be manufacturable.
When making a flat layout of a complex part, it always helps to start from a certain side, one that seems to be basic or the most complex, and unfold the remaining portions bend after bend.
A bracket, shown in Fig. 7-1, is simple enough to serve as an example of the unfolding technique. First, the A flange may be flattened out to become flush with the vertical portion. This should be done visually, just by looking at the illustration and imagining the flange rotating around its pivoting point or an axis of rotation, as if retained by hinges. Such axis of rotation is always located in the center of bend radius.
Next, the whole vertical segment should be folded down, to become a flat continuation of the horizontal section, as shown in Fig. 7-2. Such a flattened portion may be sketched, adding other segments to it as they are unfolded. To...
