If
you
pick
a
lo ck
and
the
plug
stops
turning
after
a
few
degrees
and
none
of
the
pins
34
Figure
9.5:
(a)
Driver
sets
on
b evel
Figure
9.6:
(b)
Driver
jams
on
b
ev
el
35
can
b
e
pushed
up
any
further,
then
you
known
that
the
lo
c
k
has
mo
died
drivers.
Basically
,
the
lip
of
the
driver
has
caugh
t
at
the
sheer
line.
See
the
b ottom
of
Figure
9.7.
Mushro
om
and
sp o ol
drivers
are
often
found
in
Russwin
lo cks,
and
lo cks
that
ha
v
e
sev
eral
spacers
for
master
keying.
Y
ou
can
iden
tify
the
p ositions
with
m
ushro om
driv
ers
by
applying
a
light
torque
and
pushing
up
on
each
pin.
The
pins
with
mushroom
drivers
will
exhibit
a
tendency
to
bring
the
plug
back
to
the
fully
lo ck
ed
p
osition.
By
pushing
the
k
ey
pin
up
you
are
pushing
the
at
top
of
the
k
ey
pin
against
the
tilted
b ottom
of
the
mushroom
driver.
This
causes
the
driver
to
straighten
up
which
in
turn
causes
the
plug
to
unrotate.
Y
ou
can
use
this
motion
to
iden
tify
the
columns
that
ha
v
e
m
ushro om
driv
ers.
Push
those
pins
up
to
sheer
line;
ev
en
if
y
ou
lose
some
of
the
other
pins
in
the
pro cess
they
will
b e
easier
to
re-pick
than
the
pins
with
mushroom
driv
ers.
Ev
en
tually
all
the
pins
will
b
e
correctly
set
at
the
sheer
line.
One
w
a
y
to
identify
all
the
p
ositions
with
mushroom
drivers
is
to
use
the
at
of
your
pick
to
push
all
the
pins
up
ab out
halfw
a
y
.
This
should
put
most
of
the
driv
ers
in
their
co
c
k
able
p osition
and
you
can
feel
for
them.
T
o
pick
a
lo ck
with
mo
died
driv
ers,
use
a
lighter
torque
and
heavier
pressure.
Y
ou
w
an
t
to
error
on
the
side
of
pushing
the
key
pins
to o
far
in
to
the
hull.
In
fact,
another
w
a
y
to
pick
these
lo cks
is
to
use
the
at
side
of
y
our
pic
k
to
push
the
pins
up
all
the
wa
y
,
and
apply
very
hea
vy
torque
to
hold
them
there.
Use
a
scrubbing
action
to
vibrate
the
k
ey
pins
while
you
slowly
reduce
the
torque.
Reducing
the
torque
reduces
the
binding
friction
on
the
pins.
The
vibration
and
spring
force
cause
the
k
ey
pins
to
slide
down
to
the
sheer
line.
The
key
to
picking
lo cks
with
mo
died
drivers
is
recognizing
incorrectly
set
pins.
A
mushroom
driver
set
on
its
lip
will
not
ha
v
e
the
springy
giv
e
of
a
correctly
set
driver.
Practice
recognizing
the
dierence.
9.10
Master
Keys
Many
applications
require
keys
that
op
en
only
a
single
lo
c
k
and
k
eys
that
op en
a
group
of
lo cks.
The
k
eys
that
op en
a
single
lo
c
k
are
called
change
keys
and
the
keys
that
op en
multiple
lo cks
are
called
master
keys.
T
o
allow
b
oth
the
change
key
and
the
master
key
to
op en
the
same
lo ck,
a
lo
c
ksmith
adds
an
extra
pin
called
a
sp
ac
er
to
some
of
the
pin
columns.
See
Figure
9.8.
The
eect
of
the
spacer
is
to
create
tw
o
gaps
in
the
pin
column
that
could
b e
lined
up
with
the
sheer
line.
Usually
the
c
hange
key
aligns
the
top
of
the
spacer
with
the
sheer
line,
and
the
master
key
aligns
the
b ottom
of
the
spacer
with
the
sheer
line
(the
idea
is
to
prev
en
t
p eople
from
ling
down
a
change
key
to
get
a
master
key).
In
either
case
the
plug
is
free
to
rotate.
In
general,
spacers
make
a
lo
c
k
easier
to
pic
k.
They
increase
the
n
um
ber
of
opp ortunities
to
set
each
pin,
and
they
make
it
more
lik
ely
that
the
lo ck
can
op
ened
by
setting
the
all
the
pins
at
ab out
the
same
height.
In
most
cases
only
t
w
o
or
three
p ositions
will
hav
e
spacers.
Y
ou
can
recognize
a
p osition
with
a
spacer
by
the
t
w
o
clic
ks
you
feel
when
the
pin
is
pushed
down.
If
the
spacer
has
a
smaller
diameter
than
the
driver
and
key
pins,
then
y
ou
will
feel
a
wide
springy
region
b ecause
the
spacer
will
not
bind
as
it
passes
through
the
sheer
line.
It
is
36
Figure
9.7:
Mushro om,
sp
o ol,
and
serrated
driver
pins
37
Figure
9.8:
Spacer
pins
for
master
keying
more
common
for
the
spacer
to
b e
larger
than
the
driver
pin.
Y
ou
can
recognize
this
by
an
increase
in
friction
when
the
spacer
passes
through
the
sheer
line.
Since
the
spacer
is
larger
than
the
driv
er
pin,
it
will
also
catch
b
etter
on
the
plug.
If
y
ou
push
the
spacer
further
into
the
hull,
you
will
feel
a
strong
click
when
the
b ottom
of
the
spacer
clears
the
sheer
line.
Thin
spacers
can
cause
serious
problems.
If
y
ou
apply
hea
vy
torque
and
the
plug
has
b eveled
holes,
the
spacer
can
twist
and
jam
at
the
sheer
line.
It
is
also
p ossible
for
the
spacer
to
fall
into
the
k
eyw
a
y
if
the
plug
is
rotated
180
degrees.
See
section
9.11
for
the
solution
to
this
problem.
9.11
Driv
er
or
Spacer
En
ters
Keyw
a
y
Figure
9.9
sho
ws
how
a
spacer
or
driv
er
pin
can
enter
the
keyw
a
y
when
the
plug
is
rotated
180
degrees.
Y
ou
can
prev
en
t
this
b
y
placing
the
at
side
of
your
pick
in
the
b ottom
of
the
keyw
a
y
b
efore
y
ou
turn
the
plug
to
o
far.
If
a
spacer
or
driv
er
do
es
en
ter
the
k
eyw
a
y
and
preven
t
you
from
turning
the
plug,
use
the
at
side
of
you
pic
k
to
push
the
spacer
bac
k
into
38
Figure
9.9:
Spacer
or
driver
can
en
ter
keyw
a
y
the
hull.
Y
ou
ma
y
need
to
use
the
torque
wrench
to
reliev
e
an
y
sheer
force
that
is
binding
the
spacer
or
driver.
If
that
do esn't
work
try
raking
o
v
er
the
driv
ers
with
the
p ointed
side
of
y
our
pick.
If
a
spacer
falls
in
to
the
k
eyw
a
y
completely
,
the
only
option
is
to
remov
e
it.
A
ho ok
shap ed
piece
of
spring
steel
works
well
for
this,
though
a
b ent
pap erclip
will
work
just
as
well
unless
the
spacer
b ecomes
w
edged.
9.12
Vibration
Pic
king
Vibration
picking
works