To make a tool steel-safe, it is advisable to start with a thin hinge (0.008 to 0.010 in.
(0.20 to 0.25mm) and adjust upwards if necessary, to a maximum of 0.0 15 in.
(0.38mm) Although thicker hinge sections may be employed where the required angular
movement is small, these cannot be considered as true living hinges because they
result in a lower degree of polymer orientation which may result in lower flex life.