washers to hold the focus gearbox in place (see
112). Be sure to verify the proper positioning of the
two brass shims before installing these screws.
Figure 112 – Loosely install upper screws for the gearbox
Sight through the two bottom screw holes on the
mounting flanges of the focus gearbox housing and re-
position the focus gearbox as necessary until the
mounting holes and shims are centered relative to the
tapped holes in the pillar arm casting. Hold the focus
gearbox in this position and use a toothpick or tweezer
tips to adjust the position of the brass mounting shims
as necessary so that they do not obstruct the threaded
holes in the pillar arm casting. Loosely reinstall the two
remaining M3X10 hex socket-head cap screws and lock
washers into the bottom holes of the focus gearbox
(see
Figure
113).
Figure 113 – Start the bottom screws for the gearbox
Snug all four of the mounting screws down lightly, and
then back them off a bit such that the focus gearbox is
just free enough to shift on its mounting screws.
Manipulate the sliding focus block by hand and observe
how the focus gearbox shifts on its mounting screws as
the sliding focus block is moved up and down. Hold the
sliding focus block such that the focus gearbox is
centered relative to its mounting screws (i.e., so that it
Complete Teardown, Cleaning, and Reassembly of the Olympus BH-2 Coaxial Focus Mechanism
Figure
is not straining against the mounting screws in either
direction) and tighten all four mounting screws to
secure the focus gearbox in this centered position (see
Figure
114). Verify that the coarse-focus mechanism
feels smooth when adjusted throughout its range using
the coarse-focus knobs (apply a bit of weight to the
focus block with one hand while doing this assessment).
If the motion of the sliding focus block does not feel
smooth as you adjust the coarse-focus knobs, loosen
the four mounting screws of the focus gearbox and
readjust its positioning, then re-tighten the four
mounting screws, until the motion does feel smooth.
An alternative way to accomplish the positioning of the
focus gearbox is to lay the stand down on its nose, such
that the weight of the sliding focus block no longer pulls
on the focus gearbox, and then hold the focus gearbox
in the proper position while tightening the mounting
screws to secure it in place.
Figure 114 – The focus gearbox reinstalled in proper position
Reinstall the Rear Cover
Hold the rear cover in position on the pillar arm casting
and use a suitable JIS screwdriver to reinstall the four
M2X6 pan-head screws to secure the rear cover to the
pillar arm casting (see
Figure 115 – Reinstall rear cover onto back of pillar arm
Figure
115).
Revision 4
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Halaman Cetak