Miller Electric Maxstar 200 STR - Manual (Page 36)

Om-2233 Page 30
SECTION 9 − GUIDELINES FOR (GTAW) TIG WELDING
gtaw 7/2006
9-1. Positioning The Torch
Ref. ST-161 892
Y Grinding the tungsten elec-
trode produces dust and fly-
ing sparks which can cause
injury and start fires. Use lo-
cal exhaust (forced ventila-
tion) at the grinder or wear an
approved respirator. Read
MSDS for safety information.
Consider using cerium or
lanthanum based tungsten
instead of thoriated. Tho-
rium dust contains low-level
radioactive material. Proper-
ly dispose of grinder dust in
an environmentally safe way.
Wear proper face, hand, and
body protection. Keep flam-
mables away.
1 Workpiece
Make sure workpiece is clean
before welding.
2
Work Clamp
Place as close to the weld as
possible.
3
Torch
4 Filler Rod (If Applicable)
5 Gas Cup
6 Tungsten Electrode
Select and prepare tungsten
according to Section 8.
Guidelines:
The inside diameter of the gas cup
should be at least three times the
tungsten diameter to provide ade-
quate shielding gas coverage. (For
example, if tungsten is 1/16 in
diameter, gas cup should be a
minimum of 3/16 in diameter.
Tungsten extension is the distance
the tungsten extends out gas cup of
torch.
The tungsten extension should be
no greater than the inside diameter
of the gas cup.
Arc length is the distance from the
tungsten to the workpiece.
1
10−25
°
10−15
°
6
2
3
4
90
°
4
5
3/16 in
1/16 in
6
5
Bottom View Of Gas Cup