Originally Posted by jlhmnj

Jan, you've every right to be confused, my model 12 is different. The hole you have pictured a pin goes completely threw both sides on mine My serial is about 3 mil earlier than yours. I dug out my other machine and it has your set-up, couldn't figure it out. I'm thinking it comes off from inside the machine where the two shafts couple at the gear, but that's just a guess.
Jon