TM 9-2320-363-34-2
CAB BODY REPAIR (CONT)
Table 7. Rivet Grip Length Determination
Material Thickness
Rivet
Range (In.)
Grip
No.
Minimum
Maximum
1/16
1
1/8
1/8
3/16
3
3/16
1/4
4
114
5/1 6
5
5/16
3/8
6
3/8
7/16
7
7/16
112
8
112
9/16
9
9/1 6
5/8
10
5/8
11/16
11
I
11/16
I
3/4
12
I
1.
INSERT RIVET STEM INTO PULLING HEAD OF RIVET GUN OR ADAPTER.
2.
HOLD RIVET GUN IN LINE WITH AXIS OF RIVET AS ACCURATELY AS POSSIBLE.
3.
APPLY STEADY, FIRM PRESSURE AGAINST RIVET HEAD.
4.
SQUEEZE HANDLES OF MANUAL GUN. RIVET CLAMPING ACTION WILL PULL SHEETS
TOGETHER, SEAT RIVET HEAD, AND BREAK STEM FLUSH WITH HEAD OF RIVET.
C A U T I O N
Repairs should not be made on body using welding or heat for forming. Heat
will weaken material and cause further problems.
Material
Aluminum material used for repair should be of the same alloy and temper as original, if possible. In
general, 6061-T6 should be used. Material thickness must be the same or thicker. This alloy will work well
for flat repairs, but is not well suited to bending because it is hard and cracks easily when bent sharply.
When bends must be made, use softer 6061-T4 aluminum alloy and increase material thickness by at least
50 percent. As a rule of thumb, 6061-T4 should be bent with minimum bend radius of one to two times
material thickness, whereas 6061-T6 requires at least three times material thickness radius for bends. In all
cases, bends should be closely inspected for cracks. Suitable method for avoiding bending cracks is to
obtain angles that are extruded from 6061-T6 alloy, or use preformed angles for repairs.
22-22
