I bought a bunch of ASSA Twin 6000 locks off of ebay about a month ago. I opened them up, and found out that the locks had only the last 2 out of the 5 sidebar pins installed, so, I sent a message to the locksmith to get the rest of the pins. He said the reason why he doesn't put in all of the pins is because the the side pins stick after some useage. I was skeptical about this.
So a week went by, and the side pins arrived. I started to put them in the locks, but they wouldn't go in. I took out a hand lens and analyzed the holes for the sidebar pins. It turned out that they were deformed. Here is a picture of one of the moderate deformations under a hand lens:
The deformation is circled in red.
Can somebody tell me why this happens?
"Lockpicking is what robbing is all about!" says Jim King.