TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM 9-1240-401-34&P a. SETTING UP AND ADJUSTING CROSS-LEVELING FIXTURE 1 2 3 4 Secure cross-leveling fixture (1) on a solid stand bolted to the floor. Place precision level (2) on square portion of elevation shaft (3), perpendicular to axis of rotation, and center the bubble. Place precision level (2) on square portion of elevation shaft (3), parallel to axis of rotation, and center the bubble. Set cant vernier scale (4) and elevation vernier scale (5) to zero. 5 Install test fixture adapter (6) on shaft of cross- leveling fixture (1). 6 Tighten eight cap screws (7) only enough to keep test fixture adapter (6) from moving while checking test fixture adapter (6) for level. 7 Using a 5-second level or known good gunners quadrant and 6-inch parallel bar positioned on flat surface of round block (8), loosen eight cap screws (7) only enough to gently tap test fixture adapter (6) until bubble in level vial or gunner’s quadrant is centered. 8 Using a 5-second level or known good gunners quadrant and a 6-inch parallel bar on square portion of elevation shaft (3), turn upper section handwheel (elevation) (9) and lower handwheel (cross-level) (10) until square portion of elevation shaft (3) is leveled in both elevation and cross-level positions. 9 With gunners quadrant still positioned as in step 7, ensure that surface is still level. Change 1 5.1-61