TM 5-3825-226-24
BASIC BLOCK
FEED ASSEMBLY INSTALLED
8. 1P2369 Torsion Bar Assembly. 9. Setscrew. 10.
1P2365 Feed Assembly. 11. Bolt. 12. Bolt. 13.
Thumbscrew.
To set tool in tool holder. Set micrometer (15) to
3.7075 in. (94.171 mm). Place centering ring (1) on
1P2370
Micrometer
Bracket
Assembly.
Move
micrometer (15) until spindle (14) contacts centering
ring (1). Tighten bolt (16). Back off micrometer thimble
and recheck micrometer setting. Repeat above steps
until micrometer setting is accurate.
SETTING MICROMETER
1.1 P2344 Centering Ring. 14. Micrometer spindle.
15. Micrometer. 16. Bolt.
Place tool holder (17) on the IP2370 Micrometer
Bracket Assembly. Align mark on tool holder (17) with
hole in shaft (18). Place tool bit (20) in tool holder (17)
and set the micrometer .070 in. (1.78 mm) less than the
finish bore diameter of 3.7175 ± .0005 in. (94.425 ±
0.013 mm). Turn the bracket assembly arm until
micrometer spindle aligns with tool bit (20). Adjust tool
bit (20) by pushing it with the 9S8521 Rod (19) until tip
of tool bit (20) touches micrometer spindle.
CAUTION
Do not sweep micrometer spindle
across tool bit.
SETTING TOOL BIT
17. 1P2366 Tool Holder Assembly. 18. Shaft. 19.
9S8521 Rod. 20. Tool bit.
Use a maximum of .025 in. (0.64 mm) rough cuts
and .010 in. (0.25 mm) finish cuts.
Wipe boring bar and tool holder clean. Place tool
holder on the boring bar, with tool bit cutting edge facing
the direction of rotation. Assemble the tool holder by
placing lower half over the bolts, slide into slot and
tighten bolts. Slide boring bar in until tool is
approximately .12 in. (3.0 mm) from the bore.
Compare tool cutting tip with bore surface while turning
bore bar by hand, to insure correct tool setting.
Set feed mechanism into feed by turning knob (23)
until pin (22) drops into slot (21).
FEED ENGAGED
21. Slot. 22, Pin. 23. Knob.
NOTE: To set the feed mechanism into feed on late]
units, turn lever (A) up (the direction of arrow).
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