Regardless of the method used to bend plate, you
must always consider the thickness of the plate and
provide an adequate bend allowance. The thicker the
metal, the more important the calculation of the bend
allowance. When working with thin sheet, you can
estimate (or sometimes even disregard) the thickness of
the material. If the thickness of the material in heavy
plate is not considered, it will cause serious errors in
specified dimensions, perhaps even a complete lack of
fit between component parts.
When bending metal to exact dimensions, you must
Figure 13-45.--Lifting template and set for shell plate.
know the amount of material required to form the bend.
Figure 13-46.--Erection aids.