FRAMES
MOTOR TRUCK SERVICE MANUAL
Riveting
Hot rivets are acceptable, as they can be more easily
driven with hand tools. Cold rivets should only be used
where tools of sufficient power to properly set the rivets
are provided.
Rivets should be from 50% to 100% as heavy in
diameter as the total thickness of the plates to be riveted.
Welding
Electric arc-welding is recommended for all frame
welding.
Fig. 5 Suggested Types of Reinforcing Plates and
Method of Attaching to Frame Rail.
The reinforcements should be welded to the frame
after the reinforcements are riveted. All unused holes
IMPORTANT: Do not weld into the corners of the
should be filled with welding material. The welding rod
frame or along the edges of the frame side rail flanges
should be substantially the same material as that used in
"A", Fig. 5. Welding at these points tends to weaken the
the frame.
frame and encourage development of new cracks.
Preparation Of Frame For Repair
Use only the shielded-arc method for all frame
welding. Heat generated during welding is localized and
Before welding the reinforcement to the cracked
burning of material is minimized whenever this method is
section of the frame side rail, certain preparations are
used. (Fig. 6) Additional advantages are that the finished
necessary to insure strength and stableness of repair.
weld can be ground, filed, and drilled as necessary.
To prevent further spreading of the crack, a hole should
be drilled at the starting point of the crack, Fig. 4. Widen
With the reinforcement positioned in the frame side
the crack its full length, using two hacksaw blades
rail, follow the welding patterns shown in Fig. 5 as
together. Groove or bevel both sides of the crack to
closely as possible.
permit the weld to penetrate to the surface and establish
a solid contact between the reinforcement and the frame
side rail. Grooving can be accomplished by grinding or
with a cape chisel.
Fig. 4 Showing Method of Drilling Frame Rail to Stop
Fig. 6 Weld Sample Showing Lower Heat Dissipation
Progress of Crack. Also shows Method of Preparing
Possible with Shielded Arc Welding.
Crack for Welding.
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