December 1 997
try the plug back in the shell. It
should tum freely. If not, the tum-
blers weren't as right as you
thought. Sight along the body of
the plug. With the key still in-
serted, the "good" tumblers
should not extend out beyond
the diameter of the plug. Look-
ing good and moving freely are
the tests as you install more tum-
blers. Kinda like my social life.
Now to fit the rest of the tumblers.
Look at the tumblers. Notice that
the width of the end opposite the
spring end varies from tumbler
to tumbler. This dimension de-
termines the depth of the key cut
that corresponds. Lets call that
the "working end." A deep cut
on the key needs a tumbler with
a large end and vice versa. Here
is a trick. With the key in the plug,
pick one of the unfilled tumbler
slots and look down into it to
determine how deep it is. Note
that the key cut faces the non
spring end of the slot, so the non
spring end gets our attention.
Disk tumbler
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____,
J
STAR .... TECH JOURNAL
We are simply holding the tum-
bler 180 degrees out of position
to see if its working end is the
right size. If it is, pull it out, turn
the plug over, remove the key,
drop in a spring, and drop the
tumbler in the slot. Tap it into
place so it will be retained. It
should move easily against the
spring. Insert the key again and
check for operation. Do this for
each tumbler until you have
them all. The lock should now
work properly.
If you are just doing one lock, the
likelihood is that you will wind
up with an extra tumbler and a
vacant tumbler slot. A lock that's
a tumbler short is better than no
lock at all. Replace it when you
can. I keep a little fuse tin full of
tumblers in my tool kit. In the
shop you should be able to come
up with enough tumblers. This
procedure can bail you out of a
tight spot. It also can help you
make a number of keyed alike
locks. A large arcade piece with
half a dozen locks on it is much
more convenient to work on if
the locks are all the same.
Don't grind down the tumblers
to make a new key work. It
makes a mess and allows many
keys to operate the lock.
"working end"
this dimension varies, it
.__ determines depth of key cut
Select one of your loose tumblers
and temporarily stick its working
end into the slot. Sight along the
plug. The proper tumbler will
line up the inside edge of its cen-
ter hole with the body of the plug.
THE
Ow
DRILL
Our
What do you do when
the game is locked and
the keys are gone? Maybe the
lock broke or a piece of key is
stuck way down there. It happens
to all of us, you can't pick the
lock, but you have to get in.
Sometimes you have to destroy
the lock. Exercise caution, we
don't want to damage the equip-
ment, and in the case of some
equipment like jukes if you drill
out the lock and the back falls off,
you still have a problem. You
have to retrieve the works so you
can release the catches. Before
you do anything final, check to
see if you can get at the back of
the lock some other way. Why
not just unscrew the cam from the
lock if you can. I can recall pull-
ing the marquee glass on a video
and reaching around the light fix-
ture to free the rear door. But if
you must, you must. Grab the
drill kit.
Key with disk tumbler
Keep in mind what is behind the
lock. The lock itself will be a write
off, but we don't want to damage
anything else. You need a basic
strategy. If you are trying to get
into a coin door, all you need is
for the lock to turn or the cam to
come off the lock. In the case of
a jukebox or some pinball heads,
we would prefer the locking
mechanism to remain intact, we
don't want it coming off the lock.
If it does come off, then it can be
very difficult to work it to open
the door. I usually try just to drill
out the part of the lock where the
tumblers are. When the tumblers
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