TM 55-203
Figure 5-3. Lowering completed underframe on trucks.
Section III. REPAIR PROCEDURES
ease of handling. After careful measuring and planning,
5-7. General
the required template is constructed. The template is used
to mark for cutting the desired piece from a steel plate,
The usual procedures to be used in making typical repairs
beam, channel angle iron, or the kind of material
to car underframes and/or their components are
necessary for the repair. The template is also used for
discussed In the following paragraphs; only general
marking the new piece The piece is placed on firm, heavy
information is included. The nature and extent of the
planks supported with benches, horses, or some heavy
damage, the accessibility of the damaged parts,
base, as illustrated in figure 5-4. The template is clamped
preliminary disassembly or removal of components, and
In position on the piece, and holes and cuts are marked.
other factors determine the individual steps required for
After the template is secured, the piece is ready for
any particular repair job. Details are not discussed, but
cutting and drilling, followed by installation on the
the general procedures to be followed in repairing certain
underframe or other part of the car Figures 5-5 and 5-6
damaged parts or frame members are Indicated. Exact
show templates for angles and I-beam, respectively.
methods are based on the good judgment and experience
When it is necessary to make several duplicate parts,
of the carman.
stops on the templates (fig 5-5) save time and trouble.
b. Straightening Out-of-Square Underframes. When
5-8. Special Jobs
a car is sideswiped or receives a blow on a corner, the
whole underframe may be forced out of square. The end
a. Use of Templates. Special kinds of repairs may
and side sills may be bent so badly that they must be
require a special pattern of patch. After the method of
removed. They are later heated and straightened under
repair has been determined, a template of the patch
the press. The -center sill, body bolsters, crossties,
should be made. When a part is to be replaced by a new
diagonal braces and the remainder of the underframe can
one, a template insures that the new part will fit exactly
be left connected. Two chains are attached, one around
and that any necessary holes or cuts will be marked out
the end of each body bolster, and brought
correctly with a minimum of lifting and figuring.
Templates of skeleton construction, braced to retain
shape, are the easiest to make and to handle. A template
should
be
of
light
construction
for
5-4