METAL BODY REPAIR - OD1653 - LESSON 1/TASK 1
(a) A pick hammer is used to bring up low spots, particularly in
areas which have been badly creased or stretched and have lost their
tendency to return to their normal contour. Figure 29 illustrates examples
of pick hammering employed to raise low spots. As a rule, the pick hammer,
working from the underside of the metal, is used to hit the center of low
spots three-eighths of an inch or less in diameter.
FIGURE 29.
EXAMPLES OF PICK HAMMERING.
(b) The pick, being sharp, stretches the metal and forms a pimple on
the surface. At the same time the pimple is formed, the metal immediately
surrounding it, though not displaced or stretched, is raised. It is obvious
that accuracy in the use of the pick hammer is of the utmost importance.
e.
Metal Shrinking.
(1) General. When body panels and fenders are formed in dies under high
pressure, the sheet metal is stretched and drawn, then compressed. This
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