Hummer H1 (2006+). Manual - part 286

10-6 Body

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NOTE: In cases where the lock bolt head is inaccessible, the locking collar must be removed. Remove the collar by grinding or by
splitting axially with a sharp chisel.

Rivet Replacement

NOTE: When removing rivets, care should be taken not to enlarge the rivet holes. Enlarged rivet holes require oversize replace-
ment rivets.

Solid Rivet Removal

File a flat surface on the manufactured head, if accessible. It is always preferable to work on a manufactured head rather than
one that is bucked over, since the former will always be more symmetrical around the shank.

Indent the center of the filed surface with a center punch.

Drill through the rivet head, using a drill bit slightly smaller than the diameter of the rivet shank to avoid over sizing the rivet
hole.

Shear the weakened rivet head off with a sharp chisel. To prevent panel distortion, support the back side of the rivet and cut the
rivet head along the direction of the rivet line or the panel edge.

Firmly support the panel from the opposite side and drive out the shank with a pin punch. If the rivet is unduly tight due to
swelling between the sheets, drill the rivet shank out with an undersized drill bit.

Blind Rivet Removal

File a small, flat surface on the rivet head.

Center punch the flat surface. Support the back side of the rivet, if possible.

Using a small drill bit about the size of a rivet pin, drill off
the tapered end of the pin which forms the lock.

Shear the lock, using a pin punch to drive out the pin.

Pry out the remainder of the locking collar.

Using a drill bit slightly smaller than the rivet shank, drill almost through the rivet head.

Pry off the rivet head with a pin punch.

Tap out the rivet shank with a pin punch.

Rivet Hole Drilling

Center punch all the new rivet locations. Center punch mark must be large enough to prevent the drill from slipping out of
position, yet it must not dent the surface of the material. To prevent denting, place a bucking bar behind the material during
punching.

Ensure the drill bit is the correct size and the points properly ground (Tables 1 and 2). A no. 10 drill bit is used to install
standard 1.875 in. (48 mm) blind rivets.

Place a drill bit in the center mark for a new rivet locations or align the drill bit with the old hole when replacing the old rivets
with oversize rivets (Table 3). When using a power drill, give the bit a few turns with fingers before starting the motor to
ensure the drill does not jump out of position when the motor is started.

NOTE: Hold the drill at a 90 degree angle to the material surface. Avoid excessive pressure or letting the drill wobble. Do not push
the drill through material.

Remove all the bumps with a metal countersink or a file.

Clean away all the drill chips. Ensure that no chips are trapped between the metal sheets.

Apply corrosion-resistant sealing compound to the hole and the surrounding area.

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Body 10-7

Hole Countersinking

NOTE: Some rivet installations in the body require the rivet to be flush with the rivet material surface. In these instances, counter-
sunk or flush-head rivets are used.

When using countersunk rivets, the rivet holes must be countersunk with a tool having a 100 degree taper, so the rivet head
will fit flush with the surface.

When using a hand-operated counter sinker, the hole must be tried with a rivet so the recess will not be too deep or too
shallow. It is best to use a countersink with a stop on it so the depth of the countersink can be controlled. Typical
countersinking dimensions for blind rivets are shown in Table 4. The minimum sheet thickness that can be machined for 100
degree countersunk rivets is given in Table 5.

Do not remove the edge of the hole on the blind side of the joint.

Blind Rivet Driving Practices and Precautions

Rivets should be inspected for proper installation. The grip length of each rivet is marked on the top of its head to provide pos-
itive identification. Use of proper grip length will produce a rivet installation where locking collar is flush with the top surface
of the rivet head. Tolerance limit on the flushness is 0.020 in. (0.51 mm).

For proper rivet installation, it is imperative that the holes be properly prepared, tools be in good working order and the rivets
properly installed. When problems occur, the source of trouble could be in any of these areas.

Table 1: Drill Bit Sizes for Solid Shank Rivets

Rivet Diameter

Drill Bit Size

Drill Bit Diameter

0.0625 in. (1.65 mm)

# 51

0.0670 in. (1.70 mm)

0.0938 in. (2.38 mm)

# 41

0.0960 in. (2.44 mm)

0.1250 in. (3.18 mm)

# 30

0.1295 in. (3.29 mm)

0.1563 in. (3.97 mm)

# 21

0.1590 in. (4.04 mm)

0.1875 in. (4.76 mm)

# 10

0.1910 in. (4.85 mm)

0.2500 in. (6.35 mm)

0.2570 in. (6.53 mm)

0.3125 in. (7.94 mm)

0.3230 in. (8.20 mm)

0.3750 in. (9.53 mm)

0.3869 in. (9.83 mm)

Table 2: Drill Bit Sizes for Blind Rivets

Rivet Diameter

Drill Bit Size

Minimum

Maximum

0.1250 in. (3.18 mm)

#30

0.129 in. (3.28 mm)

0.132 in. (3.35 mm)

0.1563 in. (3.97 mm)

#20

0.160 in. (4.06 mm)

0.164 in. (4.17 mm)

0.1875 in. (4.76 mm)

#10

0.192 in. (4.88 mm)

0.196 in. (4.98 mm)

Table 3: Oversize Diameter

Rivet Diameter

Drill Bit Size

Minimum

Maximum

0.1250 in. (3.18 mm)

#27

0.143 in. (3.63 mm)

0.146 in. (3.71 mm)

0.1563 in. (3.97 mm)

#16

0.177 in. (4.50 mm)

0.181 in. (4.60 mm)

0.1875 in. (4.76 mm)

0.205 in. (5.21 mm)

0.209 in. (5.31 mm)

10-8 Body

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Blind Rivet Installation

NOTE: Ensure the proper rivet grip length is selected for each application (Table 6). Rivets can tolerate only 0.0468 in. (1.19 mm)
variation in the material thickness for each particular rivet length. For double dimpled sheets, add countersink head height to the
materials thickness.

Insert the rivet stem into the pulling head of the rivet gun or the adapter.

Hold the rivet gun in line with the axis of the rivet as accurately as possible.

Apply a steady, firm pressure against the rivet head.

Squeeze the handles of the manual gun. The rivet clamping action will pull the sheets together, seat the rivet head and the
break stem flush with the head of the rivet.

table 4: Countersinking Dimensions for 100 Degree Countersunk Blind Rivets

Countersinking Dimensions (100 Degree)

Rivet Diameter

Minimum

Maximum

0.1250 in. (3.18 mm)

0.222 in. (5.64 mm)

0.228 in. (5.79 mm)

0.1563 in. (3.97 mm)

0.283 in. (7.19 mm)

0.289 in. (7.34 mm)

0.1875 in. (4.76 mm)

0.350 in. (8.89 mm)

0.356 in. (9.0 mm)

Table 5: Minimum Sheet Gauge for 100 Degree Machine Countersunk Rivets

Rivet Size

0.0938 in.

(2.38 mm)

0.1250 in.

(3.18 mm)

0.1563 in.

(3.97 mm)

0.1875 in.

(4.76 mm)

0.2500 in.

(6.35 mm)

Gauge

0.040 in.

(1.02 mm)

0.050 in.

(1.27 mm)

0.064 in.

(1.63 mm)

0.072 in.

(1.83 mm)

0.072 in.

(1.83 mm)

Table 6: Rivet Grip

Material Thickness Range

Rivet

Grip No.

MINIMUM

MAXIMUM

Not Applicable

0.0625 in. (1.65 mm)

0.0625 in. (1.588 mm)

0.1250 in. (3.18 mm)

0.1875 in. (4.76 mm)

0.2500 in. (6.35 mm)

0.3125 in. (7.94 mm)

0.3750 in. (9.53 mm)

0.4375 in. (11.11 mm)

0.5000 in. (12.70 mm)

0.5625 in. (14.29 mm)

0.6250 in. (15.88 mm)

0.6875 in. (17.46 mm)

0.9750 in. (24.77 mm)

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Body 10-9

Aluminum Repair

CAUTION: Body repairs should not be made using welding or heat for forming. Heat will only weaken the material and lead to
further problems.

Material

Aluminum material used for repairs should be of the same alloy and temper as the original if possible. In general, 6061-T6 alumi-
num alloy 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 quite hard and cracks easily when bent sharply. When bends must be made, use softer 6061-T4 alu-
minum alloy and increase material thickness by at least 50 percent. As a general rule of thumb, 6061-T4 aluminum alloy should be
bent with a minimum bend radius of one to two times material thickness, whereas 6061-T6 aluminum alloy requires at least three
times material thickness radius for bends. In all cases, bends should be closely inspected for cracks. A suitable method for avoiding
bending cracks is to obtain angles that are extruded from 6061-T6 aluminum alloy or use preformed angles for repairs.

Epoxy Adhesive

Where it is necessary to remove parts, note that epoxy adhesive is used in joints. Use care in parts removal to avoid unnecessary
distortion. Parts should be separated by peeling action. Before parts are reassembled, it will be necessary to remove any remaining
cured epoxy from joints so parts will fit together with good, even contact. Use of epoxy requires special storage and application
procedures which do not lend themselves to repair. For this reason, epoxy will not be used for repair. To compensate for the lack of
epoxy, additional rivets should be used when making repairs to existing joints.

Rivet Patterns

Rivet patterns are denoted by the rivet spacing and the rivet edge distance. The rivet edge distance is the distance from the cen-
ter of the rivet to the nearest edge of the sheet. The rivet spacing is defined as the distance from the center of the rivet to the
center of the adjacent rivet (Figure 10-1).

The required rivet spacing is determined by the strength needed in the joint. A general feel for strength required can be
obtained by inspecting the rivet patterns in the surrounding areas. Body repairs made using single rows of rivets should be
performed using rivet spacing not greater than 1.6 in. (4.1 cm) and not less than 0.625 in. (15.9 mm). Use 1 in. (25.4 mm) rivet
spacing as a general practice for repairs. The rivet spacing used in the original construction may be greater due to the
additional strength obtained by using epoxy adhesive. Do not use rivet edge distances less than 0.375 in. (9.5 mm).

High strength joints or large area patterns may require use of a double or a multiple rows of rivets to obtain sufficient strength.

Care must be taken to assure the rivet hole patterns are transferred accurately in cases where a part with no holes is mated to
one which already has rivet holes. The hole patterns may be transferred using one of the following patterns:

Lay a new part in place, and use the holes in the mating part as a drill template. This requires the new part to be under-
neath the mating part. Care must be taken not to distort the original holes.

Use the removed part as a drill template by clamping the old and new parts together. This requires that the parts rest flat
and the rivet flange be undistorted.

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