Question: cleaning old Diebold combo lock

[camelx]

I just bought a large antique Diebold safe 42x29x25". The combination works fine, but the dial is a bit hard to turn, it feels as the wheels may be gunked up or something. I'm including pictures and wondering if someone can tell me if I can pull the back lock plate off and inspect and clean without too much risk.

What a great site and members this is, it's been great reading!

Thanks in advance.

Btw, This is a 5 number combination, which I've never heard of. It locks and opens fine, I've included the combo sheet (blocking three of the numbers.) I was told the lock was replaced 35 years ago after original owner had locked replaced after a burglary attempt. He told me that it was replaced with a matching Diebold lock. Is this a Diebold? can't find any google matches for 5 wheel Diebold. He also told me that the locksmith identified the safe as being from 1914, Nov. 16. and had whole safe refinished and included that date on the front.

[Brian Smith]

It's a Diebold, but a Herring Hall Marvin design lock. Here's an interesting link. http://eecap.org/Covered_Facilities/...arvin_Safe.htm

[Brian Smith]

Remove the 3 screws, disassemble contents, clean w/ mineral spirits, lube post (on which the wheels turn),(to lube, get fingertips greasy with clear automotive grease & spread very thin coat. No more, no less), reassemble. To determine combination, make a metal probe that fits the hole in the back. Start turning dial to the left. write the first # it stops at. the probe will drop through. turn right and repeat until the dial will not turn. that's all.

[camelx]

Remove the 3 screws, disassemble contents, clean w/ mineral spirits, lube post (on which the wheels turn),(to lube, get fingertips greasy with clear automotive grease & spread very thin coat. No more, no less), reassemble. To determine combination, make a metal probe that fits the hole in the back. Start turning dial to the left. write the first # it stops at. the probe will drop through. turn right and repeat until the dial will not turn. that's all.

Thanks so much for that Brian. So it's pretty straight forward taking apart?

Also, were these locks the only ones that were 5 numbers for Diebold?

[camelx]

any idea on the age of this lock?

Thx again!

[wylk]

Also, were these locks the only ones that were 5 numbers for Diebold?

I suspect these are really 4-number locks and the last is always the same (75). We see something similar with the UK Manifoil locks, the last number merely depends on how the lock was mounted and is always one of 0, 25, 50, 75.

Any thoughts from the experts?

[Brian Morland]

In the interest of security and slightly off topic I know but not stickily true for later Manifoils, all 4 wheels are changeable.

[wylk]

Thanks for the Manifoil note. Now I want another one (I have a Mark IV). Do you recall which one (Mark V?) started the true-4-wheel trend?

[camelx]

Thanks so much for that Brian. So it's pretty straight forward taking apart?

Also, were these locks the only ones that were 5 numbers for Diebold?

I went ahead and called a certified safe technician to come to house and clean the lock. It looked like a straight forward process, but I thought to be safe, I'd take that road. The dials were heavily gunked up with what he said that looked like axle grease. He took apart all the wheels and used carburetor cleaner spray to clean each wheel and the spacers. Then he used lithium grease lightly to re-lube everything and put it back together and it's now extremely smooth. Great to see and know what to do in the future.

As for the 5 number lock, actually it has four wheels, so the last number is the hard number as mentioned by Brian. What is different with this lock over other locks with the last number is this one does not stop at the last number or engage the cam. If you don't go to last number exactly or you pass the last number, it will not open. There is no feel or audible click when approaching the last number, the fifth number in this case.

thanks again for the great replies!

[Doug MacQueen]

Although I usually do use a small amount of lubrication on these older Diebold safe locks , I have seen many that had no evidence of any lube applied and they are still in good working order. I think the machining done on the wheel post removes any possible hardness existing on the post and exposes a smooth gray cast iron to the brass. The high carbon content in gray cast iron is is sometimes referred to as "included graphite". Any old time locksmith is familiar with super fine powdered graphite as being the lube of choice back in the day. This combined with the good wear properties of certain brasses/bronze may explain the lack of applied lubrication. This can also be seen in many cast iron mortise locks where no lube has ever been applied and it took many years of use before any serious wear occurred.