The pattern for an obtuse elbow for a round pipe is shown in Fig. 7. The setting out of this pattern requires no additional explanation to that given for previous patterns. In drawing the elevation of pipe, however, care must be taken to set it out to the required shape of bend. In the workshop dimensions are generally given in one of the three ways shown in the figure. The angle between the centre lines is sometimes given, which in this case would, of course, be 90° + 30° = 120°. Allowances for the side-seams only are shown in this pattern.