24
Section 3 Operation
General Setup. The process to set up the welder for the
basic TIG mode with a foot pedal is as simple as plugging
in the TIG pedal and setting the amperage. TIG voltage is
not conventionally adjustable and is a product of the arc
length. This is not to say voltage is not important to TIG
welding, but it is not something that can be adjusted on the
unit. In practical terms, voltage is not a concern to the user
as it is self regulating. Amperage however, is adjustable.
Setting up Amperage correctly for TIG is different as there
is no
“
sound
”
to listen for. But for each given thickness of
metal, there is an acceptable range of adjustment for TIG.
Traditionally, a general rule of thumb for TIG setup is to set
approximately 1 amp for every
.001”
of metal thickness.
For modern inverter technology, that may be too many
amps in all but the thickest weld material, particularly for a
DC inverter TIG welder such as this one. In many cases,
you will only need to use 75% to 80% of that amperage.
But if you are setting up the unit to use a foot pedal, use
the rule of thumb to begin with as you can always back off
the amperage as you are welding by letting up some on the
foot pedal. If needed, there are several online TIG apps
and calculators that you can give you starting points for
welding almost any thickness as well as general settings for
tungsten size, and gas flow rates. Use the general infor-
mation on the following pages to help guide you through
arc starting, tungsten preparation and basic welding tech-
niques.
Welding. If you are new to TIG welding, it
’
s important that
you understand that TIG welding is much slower than other
forms of welding. It requires patience and steady practice
to become proficient at TIG welding. However, most peo-
ple can achieve some level of proficiency at TIG welding if
they are patient, and are willing to analyze and adjust the
way they are welding. To start welding, set the amps de-
sired for the metal thickness you are about to weld. Before
striking the arc, make sure the shielding gas is on, and
properly set. Also adjust your Tungsten stick
-
out to about
1/8”
to begin with. If a gas lens is used, the stick out may
increase up to
1/4”
-
1”,
depending upon gas lens size. Then
follow the arc starting methods found later in this manual.
Once the arc is started, keep a loose, but sure grip on the
TIG torch to prevent cramping. An underhand hold is
good, similar to the way a pencil is held. A foregrip may be
used as well, but offers less fine control at the beginning
and requires more propping to keep the torch steady.
Practice running slowly without filler metal first. Keep the
torch head inclined away from the direction of travel, so the
Tungsten stays just above the puddle, pointed toward the
front of the puddle. Move slowly and methodically, gaug-
ing your forward movement to make sure it is steady and
paced. Imagine a thick coin is able to be placed between
the tip of the Tungsten and the weld puddle. As your skill
progresses, you will want to add filler wire to your practice.
The angle created between the filler rod should be about 90
degrees. You should insert your head in between the rod
and torch, so that your head is about at the 45 degree mark
so that it bisects the angle. This will allow you clearly see
the arc. Do not try to sit back and view the arc from above
as detail may be easily seen and puddle will be obscured.
When the puddle develops, feed the filler rod into the front
edge of the puddle, being careful not to place the filler on
top of the Tungsten, or touch it in any way. If you dip the
tungsten into the filler rod or into the puddle, you must
stop and regrind it or the Ar will become unstable. Feed
the filler in regular, timed dips as the puddle forms. If you
need, count as you time your dips until you can do it with-
out thinking. As you proceed to dip your rod into the edge
of the puddle, keep the rod close to the puddle, within the
gas cone. If the filler metal starts to melt before you dip,
you have it too close, or you have the rod inclined too
much so that heat is being directed too far in front of the
puddle. As you add the filler, be sure to pause momentari-
ly with the forward travel of the torch. If desired, a tiny
back step motion may be used to improve weld appear-
ance. There are other ways to add filler and to create a
sound weld. You can keep the filler wire in the puddle,
with the rod laying in a flatter profile and weld. As the
torch moves forward and the rod melts, the filler can be
slid, with gentle pressure, into the puddle as needed to fill
the weld. This is known as the Lay
-
Wire technique. An-
other method of welding has more to do with torch manip-
ulation than it does filler addition, is called walking the cup.
The cup is rested on the metal while the torch head is os-
cillated in a figure 8 pattern. This will require a forehand
grip typically, and a good bit of motion of your forearm to
accomplish. The filler metal should be moved from side to
side to provide an evenly filled puddle under the Tungsten.
This method requires much practice and effort, but yields
beautiful welds when performed correctly. If you cannot
see the puddle or your helmet flashes (auto darkening
types), you need to change your settings. Practice feeding
the filler wire without actually welding. Manipulating the
wire takes practice and concentration at first. The wire
should be held so that a flicking motion of two fingers and
the thumb can propel the rod forward into the puddle with-
out loosing grip on the filler rod. The rod should rest on
the two fingers most away from the thumb, while the index
and middle finger are used to advance the rod by sliding
them down the rod while they fingers lightly pinch the rod
against the thumb. If you need, count as you time your rod
dips until you can do it without thinking. As you proceed
to dip your rod into the edge of the puddle, keep the rod
close to the puddle, within the gas cone. If the filler metal
Basic TIG Operation
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