(5) Rotate the plotting disk to zero on the azimuth
scale and draw a north-south line through the east point
Final inspection is completed after repair has been
and a north-south line through the west point The lines
accomplished to insure that the materiel is serviceable
drawn in (4) and (5) should form a square.
according to the following serviceability standards. Any
(6) Rotate the plotting disk to a position where the
item containing defects disclosed by final inspection will
plotting scale bisects the corners of the square
be further adjusted or repaired to place it in a
accomplished above (7). Both diagonals, as measured
on the scale shall be 21,213 + 21 meters.
d. Vernier Assembly. The vernier assembly will be
5-2. Visual Inspection and Testing.
visually inspected and knob shall rotate smoothly
Visually Inspect and test the board plotting In
through its entire range.
e. Board Plotting Table.
With the brake lever
pressed and held, it shall be possible to rotate the table
Equipment shall present a new appearance and shall
consisting of the disk and frame assembly through the
show no signs of rust.
entire range of travel without binding. With the brake
lever released the braking mechanism shall hold the
5-3. Plotting Board M18.
table in a clamped position but allow fine adjustment of
a. Plotting Scale Flatness. With the plotting board
the vernier knob.
arranged for two-man operation, the plotting scale shall
f. Brake Adjustment. The distance between the face
lie flat on any part of the plotting disk from the "7"
of the brake shoe pad and the face of pad mounted to
graduation to the "15" graduation within 0.015 inch when
the lip of the slide (fig. B-6) with the brake lever fully
the "11" graduation is at the center of the plotting disk.
depressed, shall measure no more than two hundred
The ends of the scale shall lie flat within 0.025 inches.
and forty thousandths (0.240) of an inch minus one
(Utilize standard thickness gages).
thousandth (0.001) of an Inch. (Utilize appropriate
b. Parallelism. When alined with the fiducial edge
of the plotting scale, two grid lines which intersect
g. Scale Assembly. With the board plotting arranged
through the center of the plotting disk, shall be parallel
in both the two-man and one-man operation mode, there
to the fiducial edge of the scale within 0.015 inch
shall be no binding in any part of the scale assembly
throughout their entire length, with the azimuth scale
when the scale assembly is moved back and forth over
and vernier reading 0 + 0.1 mil and 1600 0.1 mil.
the entire plotting disk.
(Use pocket optical compactor to check errors in
h. Plotting Disk Surface. The plotting disk surface
shall have a surface that will allow clear pencil (2H or
c. Accuracy. Lines drawn forming a centrally
softer) markings and clean erasures. The surface shall
located square with sides measuring 15,000 15 meters
have no defects such as pits, digs, scratches, or stains
shall have both diagonals measure 21,213 21 meters.
which may be mistaken for pencil marks. There shall be
The board plotting shall be arranged for two-man
no signs of delimitation.
operation with the plotting scale and grid lines parallel
and a zero setting on the azimuth scale. With this
setting the following procedure shall be utilized to form
a. Fasteners. Fastening devices shall be checked by
functional and visual examination when engaged and
(1) Using the plotting scale, measure off and
disengaged The supporting and securing devices within
establish a point 7500 meters north of the approximate
the chest shall be accessible and receive and secure the
center of the disk.
(2) From the point established above measure off
and establish a point 15000 meters south.
compressed so that the lip edges displace a uniform
(3) Rotate the plotting disk to 1600 mils and
compression over the surface of the rubber seal. There
repeat procedures in (1) and (2) to establish east and
shall be no signs of delimitation.
b. Handles. All handles shall function without in-
(4) With the table set in this position, draw an
east-west line through the north point and an eastwest
line through the south point.