192 Section 2 Nonstructural Repairs
Copyright Goodheart-Willcox Co., Inc.
Two-Sided Repair, Body Line
When performing a two-sided repair that involves
a body line, the body line is the strongest part of the
damage and, therefore, must be corrected first. Most
of the damage in the low-crown area will be raised with
the body line.
The steps in performing this type of repair are as
follows:
1. Raising—Raise the body line with a body chisel.
See Figure 9-45. The body line will resist move-
ment, so hard blows on the chisel may be required
to raise the body line. Make sure to raise the body
line to its proper height.
2. Stretching—Damaged body lines are often upset.
To correct the upset and false stretch, place the
chisel on the back side of the body line and push
out. From the outside, lightly hammer on the chisel
to stretch out the body line.
3. Picking and filing—File across the damaged
areas adjacent to the body line. Look for shiny
spots that indicate high areas. Lower the high
areas by picking, while supporting the panel from
underneath with a dolly. Do not hit the dolly when
picking.
4. Shrinking—Make a shrink fence around the area
to be filled to prevent “chasing the dent” across the
panel. The shrink fence will tighten up the metal.
Arrowheads
Arrowheads are caused by lateral force on a high-
crown panel. The arrowhead is an area of upset. The
strongest part of the damage is the area at the point of
the arrowhead. See Figure 9-46.
One-Sided Repair, No Body Line
The steps in performing a one-sided arrowhead
repair that does not involve a body line are as follows:
1. Raising—Remove the paint from the repair area.
Weld draw pins in the low spots at each arrow-
head. See Figure 9-47. Starting with the upper
left pin and working clockwise, pull each pin
out slightly with the slide hammer. Repeat the
sequence, gradually pulling up each pin. Continue
working the pins up, being careful not to pull the
damage too high. Once the damaged metal is
raised to within 1/8″ of its proper height, begin the ″
leveling process.
2. Leveling—While pulling out with the slide hammer,
tap down the ridge around the arrowhead with
a flat-faced dinging hammer. Use a gradual
approach. Start at the bottom of the arrowhead and
work upward. Alternate tapping from one side of
the arrowhead to the other.
3. Raising—As the arrowheads are pulled out, weld
additional pins in any remaining low areas. Raise
these areas gradually, starting with the lowest pin
and ending with the highest. Pull each pin slightly
in an effort to gradually restore the crown in the
panel. Remove the pins and check the damaged
area for level.
4. Leveling—Any remaining high areas should be
lowered by tapping. Tapping on high areas without
supporting adjacent low or properly contoured
areas may cause the crown to collapse. Weld
draw pins in place to support adjacent low or
properly contoured areas. While holding a draw
pin to support the panel, tap any high areas with a
dinging hammer.
5. Shrinking—Any metal that was pulled too high by a
draw pin can be lowered by shrinking with the draw
pin welder. Heat the area with the welding tip, tap
the heated area twice, and then cool the area with
a wet rag.
Goodheart-Willcox Publisher
Figure 9-46. These are the parts of an arrowhead.
The point of the arrowhead is the strongest part of the
damage.
Goodheart-Willcox Publisher
Figure 9-45. A body chisel is used to move the body
line out. Note that the face of this chisel is covered
with green masking tape to prevent it from cutting the
metal.
Chisel
Arrowhead
Shaft
Arrowhead side
Arrowhead point
Arrowhead side