Mitsubishi MOTORS Lancer Evolution 2008, Body Repair Manual

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WELDING
TSB Revision
BASE OF BODY REPAIR 9-12
NOTES REGARDING MIG WELDING
Note the following notes regarding MIG welding.
1. The surface to be welded must be perfectly
clean; be sure to remove any non-conductive
paint.
2. If the end of the wire forms into a ball, it will
adversely affect the formation of the arc; cut the
end off with a pair of wire snips or a similar tool.
3. Select a welding current to match the thickness of
the panels being welded.
4. For continuous welding, maintain a constant weld
speed and keep both the height and the width of
the bead constant.
In addition, the tack welding pitch and the welding
bead should be shorter as the thickness of the
panels being welded decreases.
OTHER TYPES OF WELDING
M4090004000046
BRAZING
In brazing, a filler metal is melted into the joint of the
panels to be welded at a comparatively low tempera-
ture to fuse them together without melting the panels
themselves. In other words, through the aid of a flux
and because of the capillarity phenomenon, the mol-
ten filler metal will flow into the joint between the two
panels which are in contact with each other and
spread along the metal surfaces. When this molten
filler metal cools and solidifies, it will from a strong
joint of the two panels. Note that, if two panels of dif-
ferent kinds of metal are brazed, the electrolysis gen-
erated between the two metals will cause moisture to
from, which will result in corrosion.
Panels should not be connected together by brazing
at any place except those places indicated. The fol-
lowing materials (filler metals) are usually used for
brazing.
1. Brass filler metal (brass solder)
Brass filler metal is an alloy consisting of 60%
copper and 40% zinc with a melting temperature
of approximately 850
−
1,050
°
C (1,562
−
1,922
°
F), and it is the most commonly used braz-
ing filler metal used for body repair.
The filler metal itself is coated with flux to facili-
tate penetration between the panels to be joined.
2. Silver alloy filler metal (silver solder)
Silver alloy filler metal consists of silver, copper,
zinc or cadmium, nickel, and tin, or other metals.
This filler metal is most applicable for the brazing
of steel and non-ferrous alloy other than alumi-
num, magnesium, and others with low melting
points.
Notes with regard to brazing work
•
Use a wire brush, sandpaper, file etc., to remove
any oxide film grease, dirt, etc., from the surfaces
of the panels to be brazed.
•
When doing brass brazing, if the panels and the
filler metal are heated excessively, a weak
iron-copper alloy will form, which could crack
easily. Be careful not to apply excessive heat.
•
The joint of the panels must overlap as indicated
in the illustration.
AB200044
Examples of brazed joints
AF