Chapter 10 Raceway Systems 143 Copyright Goodheart-Willcox Co., Inc. Note that if the offset bend is going to occur after the obstruction, shrink does not have to be added into the bend location. Regardless of whether you create the offset before or after an obstruction, the bends will be made on the side of the mark that points away from the obstruction. See Figure 10-9. Review the following procedures and com- pare the steps for creating an offset bend before and after an obstruction. In all types of bends, the amount of shrink depends on the size of the conduit. Shrink varies with bend radius, and each size of conduit must be bent to the proper radius. Goodheart-Willcox Publisher Figure 10-8. This offset bend chart allows you to determine shrinkage and the distance between bends based on the offset height and angle of the bend. Offset Bend Chart Angle g l e of Bend S Sh rinkage (per in i nc h of offset depth) Dista t an ce between Bends (mu m ul tiply by offset depth) 10° 1/16″ 5.8 22.5° 3/16″ 2.6 30° 1/4″ 2.0 45° 3/8″ 1.4 60° 1/2″ 1.2 Goodheart-Willcox Publisher Figure 10-9. If the offset is to occur before the obstruction, shrink will affect the location of the bend. When the offset occurs after the obstruction, shrink will not affect the location of the bend. Direction of installation Start Finish Since the bend will need to finish here, shrink must be considered Since the bend will start here, shrink does not have to be considered