Everlast Power i-MIG 353DPi, Operator'S Manual

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PULSE MIG OPERATION
The Power i - MIG 353DPi pulse design features both Single and Double
Pulse wave forms that feature synergic control of the pulse parameters.
Simply put, this means that the complicated parameters required to per-
fect the pulse action of the welder are controlled largely by an algorithm
designed and tested by qualified welding engineers to provide smooth
and well - regulated welding performance. To understand the Everlast
Pulse MIG design and setup, it is important to recognize and discuss
basic types of Pulse MIG welding and how each is performed and man-
aged.
The Types of Pulse MIG Welders. There are many different types of
pulse MIG welders. Every brand has their own type or types of pulse MIG
welders. Over the years, pulse MIG welders have changed in design
and function and multiple types of Pulse MIG may be represented under
one brand. Many times it is difficult to pinpoint the differences in the
pulse function from generation to generation or model to model as many
companies prefer to explain the effects rather than the functions. There
are nomenclature differences as well from brand to brand and model to
model. One function may be called by one name by one company, while
the same function is called by another name by another company. Some
offer more fine tuning control over the parameters than others. Over the
years pulse MIG welders have steadily evolved. This has created a lot of
confusion and misunderstanding in the industry by users about what
pulse MIG welding is and what it is capable of. Training seminars pro-
vided to dealers of one type of brand may indeed teach that a Pulse MIG
product feature is unique or special by trademarking a name of a type of
Pulse or Pulse function, while another brand has the same exact feature
but is called by another name. It has lead to a lot of confusion in the
industry. However, to be clear, there are two major categories of pulse
MIG welders: single (or simple) pulse, and double (or pulse - on - pulse)
pulse. With most single - pulse MIGs, the power is pulsed between two
preset values, creating a simple, modified square wave output of DC.
With a double - pulse MIG, the unit simply pulses between a higher layer
and a lower layer of single pulse MIG. In the most simple terms, this
creates a more complex wave form which looks and sounds different
than a single pulse square (up and down) wave form. The main ad-
vantage of using the double pulse MIG, is potential for aesthetically
pleasing welds that closely approximates the “ stack - of - dimes ” look de-
sired in high - quality finished welds. When it is properly set - up, a Double
Pulse MIG creates a pattern of defined separation in the cooled weld
similar to what you ’ d expect to find in a well - crafted TIG weld. Though
the completed look of a double - pule MIG weld may be similar and ap-
pealing to TIG, a trained eye can still spot the difference. However,
whether or not it is 100% identical looking to TIG, double - pulse MIG
provides a visually appealing weld that stands up to the scrutiny and
expectations of most customers. Depending upon how the unit is fine -
tuned and how well practiced the operator is, an additional measure of
heat control can also be gained through the double pulse MIG process.
The Basic Theory and Purpose Behind Single Pulse - MIG. Regardless of
the type of pulse MIG we are referring to, most single - pulse MIG welders
are cycling several times a second between high and low values of volt-
age. Many single pulse - MIG welders cycle between 20 - 500 Hz. This
allows good control over the heat being put into the weld and over the
directabilty of the arc. The basic reason for using a single - pulse MIG is
to prevent overheating of the weld metal while maintaining a rapid depo-
sition rate that does not compromise fusion of the base metals. Single -
pulse MIG welding is intended to be performed in pulsed - spray mode.
Pulsed - spray is a modification of the Axial - spray mode, where the metal
actually pinches off before the wire touches the weld puddle. During the
Axial - spray mode, the arc should never short circuit. Axial - spray is
accomplished by using higher volts and amps than would be used in a
short circuit transfer process. By doing so, this forces the wire to pinch
and form a steady stream of molten droplets somewhere between the
weld puddle and contact tip. These droplets travel rapidly across the arc
and direct into the puddle. The result is fast travel speed and a smooth,
quiet arc that is not much more than a steady, quiet “ hiss ”. The down
side is that the puddle is hot and uncontrollable if used out of the flat
position. The puddle will simply run off, or melt through when trying to
keep enough metal held in place.
When single pulse mode is engaged, the wire continues to spray, but
the Voltage drops low enough to fall out of the range required for Spray
but not long enough for any metal to be deposited. The goal is one
pulse per droplet of metal. The drop in voltage during the pulse allows
the puddle to cool between the high stage portion of the pulses returns.
The result is no longer a quiet hiss, but a rather unique sound that has
often been compared to an “ angry bee ” or a “ swarm of hornets ”. More
importantly, the puddle becomes stable, heat is controlled, and out of
position welding becomes possible.
Historically, the most common applications for single Pulse - MIG weld-
ing are found in Aluminum or Stainless Steel fabrication or repair.
Currently, though, single Pulse - MIG welders are being used to MIG
braze with silicon bronze in auto body repair shops. MIG brazing is
being used where auto manufacturers are requiring this as process to
repair and join modern high carbon steels that are heat sensitive and
prone to cracking. The brazing process creates a strong joint without
having to bring the Carbon steel up to a melting point.
Pulsed - spray is also used with mild or carbon steels to allow out of
position welding while maintaining useful production welding speeds
without sacrificing penetration. In comparison, Short - circuit transfer is a
cooler and slower MIG process where the MIG wire has to extend out
from the contact tip and travels down and into the puddle before the arc
shorts and the wire melts in a relatively forceful “ blast ”. Pulse MIG
combines both processes and retains the best attributes of both short -
circuit and Axial - Spray welding.
In steel and stainless use, whether in Pulsed spray or Axial spray spe-
cial gases which enable a lower transition point into Spray should be
used to be controllable and practical. These gases are much higher in
Argon. The recommended gas is 90/10 Ar/CO2 for steel. However,
Gases may be used as high as 98/2 Ar/O2 or as low as 80/20 Ar/CO2.
For Stainless, numerous combinations can be used, but the factory
recommended setting that yields the best results is 98/2 Ar/CO2, alt-
hough 98/2 Ar/O2 may be used, or a Special Tri - MIX designed for
Spray. As for Aluminum, most MIG welding of Aluminum is already
done in spray mode to prevent incomplete fusion. All MIG welding is
done, regardless of transfer method is commonly done with Argon, or
more rarely, an Argon/Helium mix. Copper/Bronze should be welded
with 100% Argon.
Most double Pulse MIGs are largely used for Aluminum welding,
though they can be used for Stainless Steel or Steel welding or Bronze
brazing. The Double Pulse MIGs, are usually completing full cycles at a
frequency of 10 Hz or less (though there may be many single pulse
cycles within one full Double Pulse cycle). Double Pulse MIG is com-
monly associated with the “ TIG ” look, with well defined ripples. The
heating and cooling is done at a level and speed that allows the weld to
cool and begin to freeze somewhat between the high pulse stages of the
pulse cycle without extinguishing the arc or completely loosing the
molten puddle. This is done by two alternating between two layers of
single pulse and can offer aesthetic advantages over single pulse MIGs.
While heat management is also attainable, double pulse capable MIGs
are sought after as they can mimic the style and look of TIG while offer-
Section 2 Setup Guide