Basic Tig Operation - Everlast PowerMTS 251Si Operator's Manual

Section 3
General Setup. The process to set up the
welder for the basic TIG mode is much less in-
volved than for basic MIG. 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 some-
thing that can be adjusted on the unit. In prac-
tical 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, par-
ticularly 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 al-
ways back off the amperage as you are weld-
ing by letting up some on the foot pedal. For
basic details for setup, consult the guide on
pages 15 and 16. Also much of the information
in the "Basic MIG Operation" guide in this
manual is useful and applicable for TIG weld-
ing. Pay particular attention to the subsec-
tions about metal cleaning and multiple pass
welds. If needed, there are several online TIG
apps and calculators that you can give you
starting points for welding almost any thick-
ness as well as general settings for tungsten
size, and gas flow rates. The general infor-
mation found on pages 34, 35 and 36 can also
be applied to basic TIG welding procedures.
Use the information on the following pages to
help guide you through arc starting and tung-
sten preparation.

Basic TIG Operation

Welding. If you are new to TIG welding, it's
important that you understand that TIG weld-
ing is much slower than MIG or Stick welding.
It requires patience and steady practice to be-
come proficient at TIG welding. However,
most people can achieve some level of profi-
ciency 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
desired for the metal thickness you are about
to weld. Before striking the arc, make sure the
shielding gas is on, and properly set. Also ad-
just your Tungsten stick-out to about 1/8"-
1/4" to begin with. Then follow the arc
starting methods on the next page. 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 method-
ically, gauging 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. In
between the filler rod and the torch, your
head should be placed so that you can clearly
see the arc. 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 re-
grind it or the ar will become unstable. Feed
the filler in regular, timed dips as the puddle
55
Basic Theory and Function