slot in lock cylinder...

[sniper1rfa]

I have no idea where to start looking for an answer to this...

Was messing around with a small luggage lock which completely defeated me, so I cracked it open to figure out why. Found this:





What is that called, and where can I find out more about what it does? The slot interrupts an otherwise normal hole for a fourth pin.

[MacGyver101]

Just guessing, because I'm not familiar with that particular lock -- but slots like that are often used in low-security padlocks to limit the amount that you can rotate the plug.

It also possible that it might be used to keep the plug held into the lock, similar to the key-retaining wafer in many desk locks?

In either case, it doesn't look like you'd actually need to pick that fourth pin in order to open the lock.

[Evan]

+1 to MacGyver101's guess...

It either keeps the cylinder in or restricts how far you can turn it...

~~ Evan

[landeroth]

in a master 140 i tried turning into a cutaway, that is exactly what it did... it kept the lock from turning past about 45 degrees, and if you put a tension wrench in a master 140 and turn it to that limit, you may feel that the spring feels like it is becoming fairly uncoiled at that point... my guess is it is there to help maintain the life of the spring that returns the plug to center. if your lock has this spring and you felt a similar phenomenon it would help build evidence for this side of the debate. however, if it doesn't have such a spring, it would be evidence against my idea. either way, i'm really curious to know...

[landeroth]

due to more information being acquired, i must correct myself... after further delicate disassembly of the master 140, it was revealed that it didn't stop the plug from turning farther CW than intended, that is actually limited by the latching mech itself. it seems to either prevent too far CCW rotation or help hold the plug in, but doesn't seem to contact the plug on the side to help hold it in. pics of it in a lock in about 8 hours.