When the preliminary progression has been finalized, the next step is the calculation of the bend allowances for each of the bends in each of the stations, using the formula:

The results for the preliminary progression of Fig. 4.5 are tabulated in Fig. 4.8, with the calculation based on the nominal material thickness, .075. The data in the last column represent the unused bend allowance of that station divided by two. It is the amount that is to be added to the straight lengths on either side of the bend in that station. With this data in hand, full-scale CAD drawings are made for each of the stations in the progression, from which detail drawings of each of the rolls can be made.