Where the pin curl becomes more complicated and offers the diversity of hairstyles that spanned so many years is in the direction, size, and manner in which it is rolled.
Insert the pin into the small hole on the doorknob until you reach the internal locking mechanism, then turn it to unlock the door.
Insert the pin into the small hole on the doorknob until you reach the internal locking mechanism, then turn it to unlock the door.
The result should look something similar to this.
After some researching, I found out about interlocking.
That help information is very complete and accurate.