Firepower MST 140i, Operating Manual

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Firepower MST 140i
Manual 0-5338 4-21 BASIC WELDING GUIDE
Tungsten Electrode Types
Electrode Type
(Ground Finish)
Welding Application Features Color Code
Thoriated 2%
DC welding of mild
steel, stainless steel
and copper
Excellent arc starting,
Long life, High current
carrying capacity
Red
Zirconated 1%
High quality AC weld-
ing of aluminum,
magnesium and their
alloys.
Self cleaning, Long
life, Maintains balled
end, High current car-
rying capacity.
Brown
Ceriated 2%
AC & DC welding of
mild steel, stainless
steel, copper, alumi-
num, magnesium and
their alloys
Longer life, More
stable arc, Easier
starting, Wider current
range, Narrower more
concentrated arc.
Grey
Table 4-8
NOTE
The Firepower MST 140i is not suited for AC TIG welding.
Base Metal
Thickness
DC Current
for Mild
Steel
DC Current
for Stainless
Steel
Tungsten
Electrode
Diameter
Filler Rod
Diameter (if
required)
Argon Gas
Flow Rate
CFH
Joint Type
0.040”
1.0mm
35-45
40-50
20-30
25-35
0.040”
1.0mm
1/16”
1.6mm
10-15 Butt/Corner
Lap/Fillet
0.045”
1.2mm
45-55
50-60
30-45
35-50
0.040”
1.0mm
1/16”
1.6mm
10-15 Butt/Corner
Lap/Fillet
1/16”
1.6mm
60-70
70-90
40-60
50-70
1/16”
1.6mm
1/16”
1.6mm
15 Butt/Corner
Lap/Fillet
1/8”
3.2mm
80-100
90-115
65-85
90-110
1/16”
1.6mm
3/32”
2.4mm
15 Butt/Corner
Lap/Fillet
3/16”
4.8mm
115-135
140-165
100-125
125-150
3/32”
2.4mm
1/8”
3.2mm
20 Butt/Corner
Lap/Fillet
1/4”
6.4mm
160-175
170-200
135-160
160-180
1/8”
3.2mm
5/32”
4.0mm
20 Butt/Corner
Lap/Fillet
Table 4-9
TIG Welding is generally regarded as a specialized process that requires operator competency. While many of the principles
outlined in the previous Arc Welding section are applicable a comprehensive outline of the TIG Welding process is outside
the scope of this Operating Manual. For further information please refer to www.firepower.com or contact Firepower.