METAL BODY REPAIR - OD1653 - LESSON 1/TASK 1
(b) Creases in metal, at points where it is impossible to back up the
hammer with a dolly block, can often be corrected by this method. To take
advantage of a greater amount of the natural support provided by the crown
of the metal, the force of the hammer blow is spread over a large area with
a spoon.
The spoon is placed lengthwise over the ridge of the crease or
other high spot and struck a series of light blows with the hammer until the
unwanted stress is relieved and the raised portion is back to its original
shape or position.
FIGURE 28.
SPRING HAMMERING USING A SPOON.
(c) In this method of hammering, no hammer marks are formed on the
metal since all of the blows are on the spoon rather than on the metal
(figure 28).
Once the metal is back to its original crown, additional
hammering will cause the surface to sink below its original contour line,
and it may not be brought back readily. Always start with light blows and,
as the job nears completion, inspect the contour after each blow. This will
reduce the possibility of sinking the hammered surface too low.
(4) Pick Hammering. Pick hammering is one of the most difficult jobs to
master. You will need a lot of practice before you can make competent use
of this tool.
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