Key for IBM 9370 - 20

Fred Cisin cisin at
Tue Nov 26 16:41:35 CST 2019

On Tue, 26 Nov 2019, jim stephens via cctalk wrote:
> I posted on the discord channel looking for information on measuring the keys 
> (ACE cylinder locks) for duplication.
> I'm including a quote from a post by Jay on the subject.  I need to get the 
> information on measuring the depths of the cuts, as the postings I've found 
> don't mention how the depths are measured for each value.

With a depth mike (or improvise) laid across the face of the key, measure 
how deep the cylinder "section" cut is.

There is nothing stopping a manufacturer from using different depths 
and/or different nomenclature (for instance, Schlage and Kwikset house 
keys have different depths, and different numberings)
Besides depth, there are a couple of differnt spacings (7 V 8 cuts?), and 
even different center peg diameters (hence the cheap pick tools on e-Bay 
have 3 variations 7.2mm, 7.5 and 7.8)
But, fortunately, most follow the leader.

In SOME localities, code cutting is severely restricted, and sometimes 
requires that you provide proof of ownership of the lock (physically bring 
it in and/or formal request on your letterhead)

If you have the lock in hand, many locksmiths will ignore the DND, 
assuming thet YOU are the one placing that there.
'course some will duplicate a key with a piece of tape over the DND!

The numbers stamped on the key rarely correspond algorithmically to the 
depths.  Instead, they are a pseudo-random identification of the key, and 
a well equipped locksmith can look those up in a "Code Book" to get the 
depths that are required.
For example, XX2247 is one of the most common for minicomputers.

There are also "Depgh And Space" books that identify the distance between 
cuts, and what depth distance corresponds to what depth number.  But, here 
is THAT information:

On Mon, 25 Apr 2011, Ethan Dicks wrote:
> Not sure about tolerances (my brother is a locksmith but I'm not), but
> according to...
> The depths by number are:
> 1 - 0.0155"
> 2 - 0.0310"
> 3 - 0.0465"
> 4 - 0.0620"
> 5 - 0.0775"
> 6 - 0.093"
> 7 - 0.1085"
> 8 - 0.1240"

Grumpy Ol' Fred     		cisin at

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