Yale Friction Fence Fun!!!
Posted: Wed May 31, 2017 7:11 pm
So I went over someones house today to open their old bank safe and low and behold, I was greeted by the infamous Yale friction fence. I messed with the lock for about three hours before I started to feel confident that I was getting consistent enough readings to actually crack it. I have been free spinning exclusively lately but don't think I am going to be doing that with this lock. The gear drive in the lock is annoying to say the least. It is distracting and makes it difficult to feel the contact point. Due to the design of the lock, the lever only drops when turning the dial to the left. This essentially means that there is only a "right" contact point and no left contact point. In addition, the lock is dialed right, left, right, left to open. I found the contact point to be at approximately 2 however was having a lot of difficulty feeling the point consistently until I decided to tilt the dial so as to move the drive cam towards the lever nose. I finally feel like I am getting consistent enough readings to make a graph. Interestingly enough, I think I likely already have the second number because when rotating the dial to the left, after picking up the second wheel I feel a significant click as the dial rotates past L63. It only ever happens rotating left, and only after I pick up the second wheel. It seems to me that due to slop in the lock or tolerance, the lever must not be contacting the drive cam at this position but the downward force from the friction fence mechanism causes the fence to pop into and out of the second wheel gate. I believe that this is what I am feeling. I am going back tomorrow armed with my graphpaper and we will see what happens. I get the lock once I get the safe open!