TM-9-2350-261-34 Direct and General Maintenance Manual M113A2 M577A2 M1064 M1068 M1059 M901A1 Download
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TM 9-2350-261-34 PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS), INCLUDING LUBRICATION INSTRUCTIONS — Continued 0014 00 2) Lead angle and cant angle. Place gun at a lead angle of 10 deg to 15 deg off vertical. Point gun in direction of weld travel for good gas coverage, cleaning, and preheating of material. Place gun at a cant angle of 90 deg. to parent metal so filler wire and arc are directed towards apex of groove. This will give equal fusion on both sides of material, even weld buildup, good gas coverage, and equal penetration. 3) Nozzle clearance. Keep nozzle clearance of 1/2 to 5/8 inch (12 to 16 mm) for good gas coverage. Wrong nozzle clearance will cause the following: a) Oxide deposits in the weld bead. b) Force gas bubbles into the weld. c) Prevent cleaning action on the material in front of the weld pool. 4) Arc length. You will hear a smooth hissing or buzzing sound when the right arc length is struck. 5) For further welding instructions, see TC 9-237. 0014 00-13