TM-9-2350-311-34-1 Maintenance Manual for Volume 1 M109 Hull Download
Page 36 of 352
TM 9-2350-311-34-1 2-8 REMOVING BURRS, SCRATCHES, AND RAISED METAL — CONTINUED Use a fine-mill file, sharpening stone (items 9 and 23, Appx C), or abrasive paper (item 12, Appx B) dipped in dry- cleaning solvent (item 7, Appx B) to remove burrs, scratches, or raised metal. When filing aluminum, clean file often to avoid lodging file with aluminum particles that could gouge work surface. 2-9 SCREW THREAD INSERTS (ONE-PIECE TYPE) When determined feasible by inspection, damaged threads should be repaired by rethreading, use of tap or die, or by “chasing” on a lathe. Tapping holes for screw thread inserts that have mutilated threads may be repaired by drilling and tapping hole oversize and installing larger inserts, or by filling tapped hole by welding, redrilling, and tapping hole to original size. Refer to Table 2-1 for drill size and depth. Use the following procedure to remove and install screw thread inserts: 1 2 3 4 5 Drill thread insert. Refer to Table 2-1 for drill size and depth. Deflect keys inward and break off. Remove reminder of thread insert with a screw extractor. Install screw thread insert until 0.010 to 0.030 in. (0.25 to 0.76 mm) below surface of plate. Drive keys in flush with plate. 2-4