194 Section 2 Nonstructural Repairs
Aluminum Panel Repair
Operations
Aluminum panels, such as deck lids and hoods, are
installed on some vehicles. Aluminum is lighter than steel.
Additionally, aluminum is easier to recycle than steel. It
is anticipated that the use of aluminum body panels will
increase in the future.
Aluminum panels found on vehicles are usually low-
crown, bolted panels. Dents are the most common type
of damage that occurs on these panels. When repairing a
dent in a low-crown panel, care must be taken to prevent
stretching the panel. Aluminum is softer than steel. There-
fore, hammer-on-dolly straightening will easily stretch
aluminum. Do not use hammer-on-dolly techniques when
straightening aluminum.
Steel particles left over on grinder disks, sandpaper,
and files will contaminate bare aluminum. Use a new
disk or new sandpaper when working on an aluminum
panel. Also, dedicate a body file (eight teeth per inch)
for use on aluminum. Aluminum can be easily gouged
by a file. Grind the edges of the file so they will not dig
into the metal.
Aluminum is much more sensitive to heat than steel.
To prevent warpage, power sanders used on aluminum
panels should be equipped with a foam backing pad.
The use of 80-grit (or finer) sandpaper and disks will
prevent excessive removal of aluminum while sanding.
Aluminum does not change color when heated as steel
does. Controlled heat is very beneficial in repairing
aluminum. Stretched aluminum can be shrunk with a
butane-powered micro-torch. The technique is similar
to that used for steel. Remove the paint from the panel
before heating the damaged area with the micro-torch.
Figure 8-63. Lead is still used as filler in some shops. A—The flux is spread with a brush. B—The heat from the
panel should soften the lead. C—Softened lead is applied to the fill area. Notice the distance between the flame
and the lead. D—A wooden paddle is used to smooth the softened lead.
Flux
A
C
B
D
Lead
Lead Paddle Flame