Full Product Manual

76
General Setup of Amps and Volts.
When welding in standard with the Lightning MTS, the two
main functions that require adjustment are Voltage and Wire
feed speed. The function of voltage in MIG welding is to
control the overall width and to a great extent, the height of
the weld bead. In other words, voltage controls the bead
prole. The wire feed speed directly controls the amps, and
in turn amps control penetration. When setting the welder
up you will notice that the WFS (Wire Feed Speed) is dis-
played in Inches Per Minute. For MIG, Amp output is con-
trolled with through control of the wire speed, so one is
related to the other. But Amps are not exactly the same
thing since wire feed speed, wire diameter, and wire type all
gure into the Amp equation. The relationship between wire
diameter, wire speed and amps is easily gured with the
following approximate industry conversions for steel:
.023”: 3.5 x Amps = Inches per minute (IPM)
.025”: 3.1 x Amps = Inches per minute (IPM)
.030”: 2 x Amps = Inches per minute (IPM)
.035”: 1.6 x Amps = Inches per minute (IPM)
.045”: 1 x Amps = Inches per Minute (IPM)
To convert wire speed (IPM) into approximate Amps, use the
following conversion formula:
.023”: IPM ÷ 3.5 = Amps
.025”: IPM ÷ 3.1 = Amps
.030”: IPM ÷ 2 = Amps
.035”: IPM ÷ 1.6 = Amps
.045”: IPM ÷ 1 = Amps
Keep in mind these are approximate conversions and do fall
off in accuracy as amps are increased into the upper current
limits for the given wire diameter.
Even though you will nd general recommendations about
setting the Amps, Volts and even shielding gas through a
variety of free downloadable apps and online calculators,
every ller metal manufacturer has its own specic parame-
ters for Volt and Amp settings for each wire diameter and
class of wire. The ranges of volt and amp parameters gener-
ally varies somewhat from brand to brand, so be sure to read
the packaging and/or manufacturer literature to determine
what range of settings are recommended. The wire diameter
also limits the practical maximum thickness of what can be
reasonably welded. The issue with following charts, graphs
and calculator recommendations is that most people nd
them either too hot or too cold. For some people, it may not
even close. However, nothing can substitute for watching
the arc and listening to the sound of the arc. A crisp, steady
sound, frequently referred to as a “Bacon frying sound””
should be heard. The actual frying sound can vary somewhat
and may have somewhat of a high pitch whine to it some-
where between the sound of a flying bee and a mosquito. If
these sounds are present, look at the arc to see if it is
steady, and producing low amounts of spatter. If large
amounts of spatter are present, the puddle seems fluid
(appears wet) and the wire speed is within the targeted
range, decrease volts a little at a time to reduce the spatter.
If this does not correct the problem, change the torch angle
and torch height. Hold the torch more vertical, with less than
a 15 degree deviation from vertical and reduce stick-out of
wire to 3/8” or less. If this still does not help, reduce the
wire speed. Some spatter is normal, though it should be
minimal overall.
The wire can also pop and spatter if the voltage is too low for
the wire speed and/or wire diameter. This is mostly ob-
served as flying bits of red-hot but un-melted wire, along
with popping as the wire inconsistently stubs into the pud-
dle. This is followed by the wire pushing back against your
hand pressure while the wire visibly turns white/red hot
before burning off. Too low of voltage will also produce a
high piled bead with the toes (edges) of the weld not proper-
ly wetting in resulting in poor fusion.
Inductance
The third important variable in setting up the Lightning MTS
is the Inductance control. This third adjustment can greatly
vary the feel of the arc at any given volt and amp setting. It
is used to balance the stiffness of the arc against the wetness
of the arc. Some professionals refer to the “buttery-ness” of
the arc. “ Buttery-ness” is arguably somewhat a subjective
term. However, it generally refers to how smooth and fluid
the arc feels and looks. In fact, the inductance alone can
affect how much wire speed or voltage is needed in any
given application. It does not typically require altering of the
Volts or the Wire Speed settings. However the arc force
control can expose poorly selected Volt/Wire Speed parame-
ters by magnifying the effects.
While Everlast uses the term “arc force”, it is known by
many different terms. Often it is referred to as inductance,
choke or slope. Simply put, the arc force (Inductance) ad-
justment controls how long it takes the current to recover
and rise to the established welding current to melt the wire
after the wire contacts the puddle and the current falls. This
process is happening many times a second so it isn’t visible
to the naked eye. But the overall effect is visible as the wire
burn off height is changed and a change in the wetness of
the puddle and how easily the molten metal flows in toward
the toes of the weld as it melts off. If the unit has sufcient
arc force, the edges of the weld will easily wick into the pud-
dle with little or no spatter with little or no manipulation of
the torch required. The pitch of the arc will be medium.
With too much inductance the puddle may be uncontrollable
and the arc will have a throaty, raspy sound. Too little
inductance and the puddle will be narrow and possibly have
a high ridge in the center. The pitch will be very high and
the puddle will seem sluggish and less fluid.
MIG OPERATION AND THEORY
Section 3 Basic Theory and Function