IMPOR
TANT INFORMA
TION
15
MIG 140 INVERTER WELDER 058-9305-6
Gas selection
Different materials require different shielding gas when MIG welding. Refer to the set up chart inside
the wire drive compartment.
Mild steel: Use 75% Argon and 25% for reduced spatter and reduced penetration for thinner
materials. Use CO
2
for deeper penetration and increased spatter.
Note: Do not use argon gas concentrations higher than 75% on steel. The result will be extremely
poor penetration, porosity, and brittleness of weld.
Stainless steel: Use a mixed gas consisting of Helium, Argon, and CO
2
.
Aluminum or bronze: Use 100% Argon.
Electrode
The welding electrode is a rod coated with a layer of flux. During the process of welding, electrical
current flows between the electrode (rod) and the grounded metal work piece. The intense heat of
the arc between the rod and the grounded metal melts the electrode and the flux. The most popular
electrodes are mentioned below:
Torch travel
Refers to the movement of the welding torch along the weld joint.
Travel direction
Refers to the direction of the torch moving along the weld joint in relation to the weld puddle.
Travel speed
The rate at which the torch is being moved along the weld joint.
Type of
electrode
Tensile strength
Application
E6011
60,000 PSI
Deep penetration process
E6013
60,000 PSI
Poor fitup application
E7014
70,000 PSI
High deposition and fast travel speed with light
penetration process
E7018
70,000 PSI
Tack welding and out of position application
