175 Chapter 9 Nonstructural Panel Repair
Copyright Goodheart-Willcox Co., Inc.
Analyzing Damage
The next step in the repair process is to analyze
the damage. The collision repair technician must be
able to identify high and low spots in a panel. Begin-
ners can feel that a panel has ripples, but they often
cannot determine if a particular spot is a high spot
(above level) or a low spot (below level). t
The first way to develop this skill is to carefully
examine the panel by sight. If the panel has paint on
it, examine the panel inside the shop, out of direct
sunlight. Sight the overhead light reflection in the
painted surface. If there is a bend in the reflection,
there is a dent in the panel. Study the damage care-
fully.
Next feel for damage. Use your entire hand as
shown in Figure 9-2. Extend your arm and slowly drag
your hand toward your body. It is important to use your
entire hand and not just your fingers. Feeling with just
your fingers will not reveal all the damage. A shop
towel placed between your hand and the panel will
reduce friction and make irregularities easier to feel.
A towel must be used to find dents on a bare metal
panel, as the bare metal produces a great deal of
friction.
On a panel that is crowned in only one direction,
a straightedge can be used to identify highs and lows.
Figure 9-3 shows a straightedge being used on a door.
The door is crowned from top to bottom. The straight-
edge is held perpendicular to the crown. If the straight-
edge rocks on a point, the point is a high spot. Low
spots will be seen as gaps between the straightedge
and the panel.
Once high and low spots have been identified
with a straightedge, go back and feel them. Note the
difference in feel between a high spot and a low spot.
A straightedge cannot be used on a double-crown
panel (a panel crowned from left to right and from top
to bottom). On this type of panel, you must rely on your
ability to feel the highs and lows.
As you check the panel for the high and low spots,
identify all the buckles. When studying the damage,
think through the collision event and ask yourself the
following questions:
■ Are body lines involved?
■ What types of buckles are found?
■ Are buckles consistent with the force direction?
■ Has the overall length of the panel changed?
■ Has the surface area changed?
■ Did longitudinal force cause folding?
■ Did lateral force cause stretching or arrowheads?
■ Are internal braces or inner panels damaged?
■ What part of the damage is the strongest?
By answering these questions, you will have forced
yourself to look closely at the damage. A careful anal-
ysis of the damage is essential to making a proper and
quick repair.
Only after you carefully examine and analyze the
damage will you be able to decide if the damaged part
should be repaired or replaced. One way to determine
this is to compare the cost of repair to the cost of
replacement. If the cost of repair is more than 75% of
the replacement cost, the damaged part is generally
replaced. For example, the estimated time required
to repair a dented fender is 4 hours. At the shop labor
rate of $50 per hour, the cost of repair would be $200.
The cost of a replacement fender is $150, plus 2 hours
labor to install the fender. The total cost of replace-
ment is $250. The repair cost is more than 75% of the
replacement cost, so in this example, the fender would
be replaced rather than repaired.
Goodheart-Willcox Publisher
Figure 9-2. This technician is using his hand to
identify high and low spots. Always use your entire
hand when feeling for damage.
Goodheart-Willcox Publisher
Figure 9-3. A straightedge can be used to identify
highs and lows in a panel. Note that a low spot is
visible near the 12 1/2″ mark. ″