Cotter pins, also called Split pins, are a retaining pin used to hold other load bearing pins in place. The goal of a cotter pin is to remain in place. The legs are spread to keep the head in place so that the pin doesn’t fall out.
There are two methods to bend the legs:
Bend the legs 15*
Bend the legs all the way back up and around
By bending the legs 15*, the pin is held in place with minimal strain on the metal of the pin. If the metal legs are fatigued too much, they can break off and the head of the pin will then fall out.
Bending the legs all the way around looks more secure, but it stresses the metal a lot more than a simple 15* bend.
Watch this video to see the difference in durability between these two methods of bending cotter pin legs.
