15 Jul
2015
15 Jul
'15
6:49 p.m.
Wow! should I dig out my Herty-Gerty?
On 16/07/2015 00:13, Jay Jaeger wrote:
> One size fits very many, but not all. I know for sure that the PDP-8/L,
> PDP-8/m, PDP-12, PDP-11/20, PDP-11/40, PDP-11/45 and VAX-11/780 all use
> the same xx2247 key. My PDP-11/24 has a silly plastic "anti static"
> key, but the xx2247 works there, too. But my PDP-11/05 and GT40 use a
> different kind of more "normal looking" key.
On Thu, 16 Jul 2015, Pete Turnbull wrote:
To the best of my knowledge, there are only three
keys: the tubular XX2247
which is used on most -8s and -11s including my 8/es and 11/34, the one that
looks like a filing cabinet key used on just a few machines (all keyed
alike), and the plastic "key" used on later Vaxen as well as the 11/24 -
albeit in a variety of colours of plastic.
We had a similar discussion four years ago.
To oversimplify slightly,
XX2247 is a very ordinary "ACE" lock/key from Chicago Lock Company.
"XX2247" is not the depths of the cuts of the key. Instead, it is
an "index" into the code.
If you have access to the right "code book", you look that up and it gives
you a sequence of key cut depths, expressed as numbers. If you DON'T have
the right code-book, then you can measure the depths of the cuts.
Thus, if you look up "XX2247", you get: 5 1 7 3 7 5 7
If you have ACE compatible key cutter, then you set those numbers for the
cuts. If you don't have a suitable cutter, then you can look up what the
physical measurement is for each of those numeric cut names (provided
below) and then use a small end-mill in a drill press.
Four years ago, Ethan Dicks, who is quite familiar with the XX2247 key
looked up the appropriate numbers in response to some speculation:
> Here's what I got from two original XX2247
keys...
> The cut depths, clockwise from the first position, looking into the
open
> end with the key at the "twelve
0'clock" position are:
> Key 1 Key 1 Key 2 Key 2
> 0.0770" 1.94mm 0.0785" 1.95mm
> 0.0150" 0.37mm 0.0155" 0.39mm
> 0.1055" 2.68mm 0.1070" 2.72mm
> 0.0435" 1.13mm 0.0455" 1.13mm
> 0.1075" 2.72mm 0.1085" 2.74mm
> 0.0780" 1.96mm 0.0785" 1.98mm
> 0.1075" 2.72mm 0.1095" 2.77mm
> I'm not quite sure what this says about cutting tolerances or what
multiple
> the depths of cut are.
On Mon, 25 Apr 2011, Ethan Dicks wrote:
Not sure about tolerances (my brother is a locksmith
but I'm not), but
according to...
http://www.locksafesystems.com/depth_and_space.htm#Chicago_Tubular_Space_an…
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"
Meaning that the XX2247 key would have depths (in the order you
describe) of 5-1-7-3-7-5-7
A locksmith set up for ACE cutting would have the code book to convert
the serial number into the depth sequence, so the number on the key is
the important datum. Knowing the numeric depths is handy when you are
pinning a lock so you know which bin to pull pins from.
-ethan