At
the
end
of
the
X/Y
calibration,
the
printer
measures
the
reference
height
above
each
of
the
9
bed
sensor
points
and
stores
the
reference
heights
in
nonvolatile
memory.
During
normal
bed
leveling,
it
is
expected
that
the
PINDA
probe
triggers
no
more
than
1
mm
from
the
reference
value,
therefore
the
nozzle
is
not
allowed
to
move
more
than
1
mm
below
the
reference
value
during
the
bed
calibration.
If
you
moved
the
printer,
you
may
need
to
re-run
the
Z
calibration
to
sample
new
reference
Z
height
values
reflecting
the
twist
and
bend
of
the
table
surface
the
printer
is
sitting
on.
If
that
does
not
help,
please
verify,
that
the
PINDA
probe
is
aligned
with
the
sensor
points
on
the
bed
during
the
bed
Z
calibration.
The
alignment
shall
be
ensured
by
the
automatic
X/Y
calibration
routine.
If
the
PINDA
probe
is
no
more
aligned
during
the
Z
calibration
over
time,
it
is
possible,
that
a
pulley
is
slipping
or
something
on
the
machine
frame
got
loose.
3)
Bed
leveling
failed.
Sensor
triggered
too
high.
Waiting
for
reset.
Similar
to
case
2).
This
time
the
PINDA
sensor
triggered
more
than
1
mm
above
the
reference
height.
Before
doing
anything
else,
make
the
Z
axis
level
by
going
all
the
way
up
and
try
again.
6.3.6
Calibrate
Z
Calibrate
Z
is
located
in
the
Calibration
menu.
It
is
always
done
with
the
steel
sheet
on.
It
should
be
performed
whenever
you
move
the
printer
to
a
different
location.
It
saves
the
heights
of
all
9
calibration
points
in
nonvolatile
memory.
Stored
information
is
used
every
time
mesh
bed
leveling
is
called
during
a
print.
When
the
measured
values
are
vastly
different
from
the
stored
values,
the
is
canceled
because
it
is
a
good
indicator
something
is
wrong.
Calibrate
Z
is
a
part
of
the
routine
Calibrate
XYZ
so
there’s
no
need
to
run
it
after
a
successful
Calibrate
XYZ.
It
is
a
good
practice
to
run
this
procedure
every
time
you
travel
with
the
printer
or
the
printer
is
shipped
the
geometry
might
change
slightly
and
cause
an
error.
At
the
start
of
the
Z
calibration
procedure
the
printer
homes
X
and
Y
axis.
After
that,
Z
axis
will
begin
to
move
up
until
both
sides
touch
the
printed
parts
at
the
top.
Please
make
sure
the
Z
axis
went
all
the
way
up
and
you
heard
a
rattling
sound
as
the
Z
stepper
motors
skip
steps.
This
procedure
ensures,
that
1)
the
X
axis
is
perfectly
horizontal,
2)
the
nozzle
is
in
a
known
distance
from
the
bed.
In
case
the
Z
carriage
did
not
touch
the
end
stoppers,
the
printer
could
not
possibly
know
the
height
of
the
nozzle
above
the
bed
and
it
could
therefore
crash
into
the
bed
during
the
Z
calibration
procedure.
The
Z
calibration
procedure
also
prompts
you
to
"Please
clean
the
nozzle
for
calibration.
Click
when
done."
20