Missing Top Pin?

[GuardianRobot]

Hello All,
I recently took apart my Sargent Mortise Cylinder and was surprised to find that the first pin stack seemed to be missing a top pin. Is this possibly the case or is it more likely that I lost it somewhere in the disassembly process (entirely possible, though unlikely) ?

My second question is what purpose, if any, the two and three top pins (in the 5th and 6th pin stacks) serve besides master keying?

Here is a picture of the pins in question (in case it isn't clear, the gap is the shear line, so the 1st, 2nd, and 3rd pin stacks have two bottom pins each) :


Thanks,
GuardianRobot

[Evan]

@GuardianRobot:

Agreed that your first stack appears to be missing a top pin if you didn't lose track of it during disassembly...

Only 4 chambers of that cylinder appear to be legitimately master keyed with proper master pins, they are from the bow: 1, 2, 3 and 5... Chamber 6 has a #9 or #0 (deepest #10) bottom pin and there is no #1 master pin so if those three pins above it came out in that actual order, they aren't serving as master pins and might just be "oops" pins left over from the last time it was re-keyed...

You also appear to be using a 5-pin length keyblank for a 6-pin lock, which is why you only have half a flat for the 6th pin... Weird... What keyway is that, is looks like it is a "?E" but I would need to see a picture of the keyway milling on the other side to be 100% certain...

~~ Evan

[SnowyBoy]

I agree, pin #6 with the extra stacks above is pretty useless as you couldn't get anything other than a 9 on there anyway. Prolly a case of bad pinning by the last person who took it apart.

I'd say the two extra upper pins in stack six actually belong to stacks 1 & 4 instead.

[GuardianRobot]

Here is the keyway:


I got the lock second hand, which could explain the abnormal pinning.

@SnowyBoy, do you mean that the bottom two pins in stack 6 belong in stacks 1 & 4 or the top two?

Is it dangerous for picking to be missing a top pin? I guess I am just a little worried about mangling a spring that could drop into the plug.

Again, thank you both for the quick responses.

[ckc123]

something seems strange with the first 2 pins. If you look at pin #1 and #2 and turn the master pin (thin one) on pin #2 sideways, there does not (visually) seem to be a gap that lines up between the first two pins (so you could even turn the cylinder with that key).. it's may be an optical illusion based on the photo, but something is strange

[ckc123]

With a bit of photoshop magic, this is what I'm trying to describe..

[Evan]

@ckc123:

The master pins for those stacks are flipped over in the picture...

The second stack would even out with a thin #2 master pin and would totally even out with the third stack with a #4 pin...

Bottom pins alone I would totally agree with what you are saying...

@GuardianRobot:

Perhaps you could take another picture with the pins stacked more tighter against the key like the photoshop job ckc123 made...

Then it might be possible to determine which pins belong where...

~~ Evan

[Poff]

I just took apart the LFIC cylinder on my wife's business to clean it up because it was hanging up and it was missing the 6th top pin. No wonder it was sticky.

[GuardianRobot]

There is a shear-line (see attached) where the gap is (it isn't clear in the first picture). My main question is why someone would have pinned the lock without a top pin in the first pin stack. Any ideas?

[Evan]

@GuardianRobot:

They wouldn't have pinned a lock intentionally with no driver pin in the stack, but sometimes they fall out when the cylinder is being re-keyed or serviced and the lock ends up missing one if the person working on it doesn't notice...

~~ Evan

[GuardianRobot]

Thanks for the help all!
-GuardianRobot