METAL BODY REPAIR - OD1653 - LESSON 1/TASK 1
At the same moment, the dolly block bounces away from the under surface of
the damaged metal and quickly rebounds against the low spots, raising them
before the next stroke of the hammer. With free whipping blows of the
hammer on the outside surface of the metal, the two handtools rapidly smooth
the rough spot.
FIGURE 13. USING HAMMER AND DOLLY.
(6) Never grip the dolly tightly or apply any great amount of pressure
on it, because the important automatic bounce and rebound of the dolly will
be lost. Most repairmen naturally develop a rhythm of 60 to 150 successive
hammer blows per minute as they become skillful. Bumping is only a matter
of hammering the high spots down and bringing the low spots up until the
damaged metal is again even in contour. Putting the high metal down first
is very important.
(7) Figure 14 (on the following page) illustrates a simple damage which
may occur to an outer door panel. The arrow indicates the direction of the
damaging force. X marks the outer rim of the damaged area, and Y marks the
point of impact of the hub. The line XY represents a cut at the bottom of
one of the Vchannels. Z marks the flanged edge of the panel which has been
bent sharply by the panel's collapse. It is also locked.