TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 2 Download
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TM 9-2320-387-24-2 1 33-7. RIVET REPLACEMENT (Cont’d) 1 d. Rivet Hole Drilling. 1. Center punch all new rivet locations. Center punch mark must be large enough to prevent drill bit from slipping out of position, yet it must not dent the surface of the material. ‘lb prevent denting, place a bucking bar behind material during punching. 2. Make sure drill bit is the correct size (tables 33-1 and 33-2) and point is properly ground. A no. 10 drill bit is used to install standard 3/16-in. blind rivets. Table 33-l. Drill Sizes for Solid Shank Rivets. RlVEl DRILL DIAMETER DRILL SIZE DIAMETER (INCH) (INCH) If16 #51 0.0670 3132 #41 0.0960 If8 #30 0.1285 5/32 #21 0.1590 3116 #lO 0.1910 If4 F 0.2570 5/16 P 0.3230 3/B W 0.3860 Table 33-2. Drill Sizes for Blind Rivets. NOMINAL DIAMETER (INCH) OVERSIZE DIAMETER (INCH) RNET %k RIVET DIAMETER MINIMUM MAXIMUM DIAMETER DS!!i: MINIMUM MAXIMUM I./S #30 0.129 0.132 If8 #27 0.143 0.146 5132 #20 0.160 0.164 5132 #16 0.176 0.180 3116 #lO 0.192 0.196 3116 #5 0.205 0.209 3. Place drill bit in center mark for new rivet locations, or align drill bit with old hole when replacing old rivets with oversize rivets. When using a power drill, give the bit a few turns with fingers before starting motor. This will help assure that drill does not jump out of position when motor is started. NOTE l While drilling, hold drill at 90” angle to material surface. Avoid letting drill wobble, making oblong holes. l Avoid excessive pressure. Let drill bit do the cutting. l Do not push drill through material. 4. Remove all burrs with a metal countersink or file. 5. Clean away all drill chips.Care must be taken to assure that no chips are trap@ between sheetsof metal. 6. Apply sealing compound (appendix C, item 61) to hole and surrounding area. I 33-8