Characteristics; Disassembling The Watch; Uncasing; Removing The Dial - Bulova 11 ANAC Technical Bulletin

Characteristics
11 ANAC
1. The oscillating weight arbor is
soldered to the combined bridge.
In the rare case that it might be
necessary to replace it, a new com-
bined bridge is required.
2. The minute wheel spring has been
riveted to the pillar plate in order to
make sure that the watchmaker will
not lose it or forget to replace it after
servicing. It is, therefore, part of the
pillar plate and not available sepa-
rately.
3. Beryllium-made bushing for the top
pivot of the sweep second wheel is
fitted inside the bottom part of the
oscillating weight arbor and for that
reason oiling is done through the
oscillating weight arbor with an
appropriate oiler. Bulova recommend
oiling this bushing from under the
bridge, before setting the latter.
Disassembling the
watch
Uncasing
Excluding the one-piece, «rnonocoque»
cases, the movement is normally held
in the case by two casing clamps (191)
and two casing screws (45C).
Removing the dial
After removing the hands and releasing
the two lateral dial screws (47), the
dial may be removed. The day star with
dial disk (591) can be lifted up and after
removing the three date indicator
guard screws (577), the day and date
mechanisms can be removed.
A dial rest (148) is used for day date
watches (caliber 11 ANACB) having a
flat dial.
Checking the automatic gear
By moving the oscillating weight (344)
in both directions, the transmission of
the power from the oscillating weight
(344) to the ratchet wheel (13) can be
checked.
Removing the oscillating weight
The oscillating weight is held in place
by a gib (343). To remove it, unscrew
the gib screw (336) and remove the gib.
.~
,
.
, f
Figure 1
Removal of the balance wheel and
pallet
Figure 2
Removal of the barrel
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Releasing the mainspring
With the oscillating weight (344)
removed, the mainspring can be re-
leased by simultaneously disengaging
the ratchet click (32) from the ratchet
wheel (13) and pressing with a pointed
tool on one arm of the breguet spring
(326) through the hole made in the
upper bridge for automatic device (341).
Turn the winding crown one quarter of a
turn forward and then let the automatic
train «run down" by turning the winding
crown slowly backwards.
NOTE: Simultaneous disengaging of the
ratchet click (32) from the ratchet
wheel (13) and pressing on the breguet
spring (326) can be done easily with
one hand, using a tweezer sufficiently
open to hold the ratchet click with
one point and pressing on the breguet
spring with the other.
2
Cleaning the escapement
As shown in figure 1, the balance and
pallet are readily removed without
disassembling any other parts of the
movement.
The mainspring barrel
Figure 2 shows how easily the main-
spring barrel (1S) is removed without
disassembly of the self-winding
mechanism. The mainspring arbor must
make six full turns before the brake
spring slips, which represents a total
running time of over 40 hours.
An unbreakable and life-time lubricated
mainspring -is used. Therefore, periodic
cleaning of the barrel and mainspring
is unnecessary.
RECOMMENDATION:
Do not dismantle the mainspring barrel.
In case of difficulty, replace the barrel
(1S) complete.