In Chapter 2, the lengths of the straight elements of the example shape were calculated, resulting in Fig. 2.6, which is repeated here as Fig. 4.15. The lengths of the straight elements of Fig. 4.15 will be used together with the bend allowance figures of Fig. 4.8 to determine the material distribution in the product shape in the second pass, as well as the material distribution in the product shape of all subsequent passes.

The product shape in the second pass is illustrated in Fig. 4.16, together with the bend allowance distribution from the chart in Fig.4.8:

Fig. 4.16

In Fig 4.17 the product shape of Fig. 4.16 is shown hatched, with the flat strip superimposed in phantom. In working out the roll profile and detail it should be standard practice to superimpose the product shape from the previous pass. In this way, the designer can reassess the amount of forming that will take place and ensure a smooth lead into the form. In this case, the shoulder detail shown would be an obvious choice because it reinforces the straight line path of the strip that was established by the entry guide and the starter pass. In Fig. 4.18, the flat strip is shown entering from the right, and is captured between shoulders of the bottom roll before forming begins. The 5.392 dimension is the flat strip width of 5.386 plus an additional .006 to accommodate the commercial strip width tolerance of .005, so at maximum width 5.391,...