Full Product Manual
44
TERMS RELATED TO AC TIG FUNCTIONS
Crater. The weld crater is the sunken area left at the end of the weld where the weld pool solidied. This divot is detrimental to
welds and cause cracking or create a point of weld stress as the weld metal tends to shrink at this point. The crater should be
lled before terminating the arc. In best practice, this is done during the down-slope stage of the weld cycle.
Down-Slope. During the weld cycle, the machine Amp output may be gradually decreased as the crater is lled. The amount of
time set determines the crater ll time that you have available. The Down-Slope reduces the Amps slowly until it reaches the End
Amp setting. Down-Slope time is not always necessary, particularly during basic 2T operations such as tacking. Set Down-Slope
to 0.0 when not needed in 2T mode. It is manually signaled when the torch trigger is pressed and held for the second time in 4T
mode. NOTICE: Down-Slope time should not be used in Foot-Pedal mode. Set Down-slope time to 0.0.
End Amps. The End Amp function is the nal Amp setting of the weld cycle. This is the nal current that is set before the arc is
set to terminate. The End Amp setting can be used with the foot pedal or the torch switch. However, for best tail-off of the arc
with the foot pedal, the End Amp setting should be set to the lowest value possible. If a large tungsten is used, however, a higher
End Amp setting may be required to terminate the arc cleanly. Larger diameter Tungstens make starting and stopping an arc more
difcult, so be sure to offset this issue with a higher End Amp setting, of at least 5 to 10 amps.
Foot Pedal. The foot pedal is used to start the arc and control the amperage throughout a preset range. This can also be accom-
plished with the use of the NOVA torch slider which can be ordered through Everlast. The slider switch acts the same as a foot
pedal, but is mounted directly to the torch with a set of Velcro straps. This allows quick removal if needed.
Post-Flow Time. Post Flow time is the amount of time that the shielding gas flows after the weld is terminated. This helps to form
a protective pocket of shielding gas around the still molten, or cooling weld to prevent harmful oxygen from the atmosphere from
entering the weld and oxidizing it. Post-Flow time is also used to cool the torch head and consumables. Long weld times require
more Post-Flow Time, but for small welds, 1 second of post-flow for every 20 amps set is usually sufcient.
Pre-Flow Time. Pre-flow time is the amount of time that the shielding gas flows before the start of the weld. This is used to help
provide clean arc starts and prevent oxidation of the weld metal by forming a pocket of shielding gas around the weld area before
the arc starts. It also preserves the point on the Tungsten. Typical Pre-Flow times range from .5 to 1.5 seconds.
Pulse. The Pulse on this unit features both standard pulse and advanced AC pulse. Standard pulse can be used in both AC and
DC modes. (Aluminum, Stainless, and Steel). Advanced AC pulse is for welding aluminum only and is only available in AC mode.
Pulse is simply the cycling of the AC or DC current between a high amp value and a low amp value. Pulse frequency (Hz) con-
trols the number of times this happens per second. Pulse Time-On controls how much relative time the pulse lingers in the high
amp stage or the low amp stage of the pulse.
The advanced pulse is actually a mix of AC and DC-. This can be used for improving penetration on thick metals, or for improving
bead prole on thin metals.
Standard Pulse is used to for several purposes:
1. To control heat. The pulse is used to help constrict the arc to prevent spreading of heat
2. To direct the arc. The conning action on the arc that the pulse improves directabilty of the arc when corner joints or tight
places are being welded.
3. To improve appearance. The pulse can be slowed to provide, smooth, evenly spaced ripples in the weld, often referred to as
the “stack of dimes” appearance. While it also helps to control heat in this mode, the effect is primarily for aesthetics.
See more information on pulse later in this manual.
Start Amps. The Start Amp function sets a beginning Amp setting that the arc starts with. This can be set low for thin materials, or
high for thick aluminum which requires a heavy “punch” of Amps to develop a weld puddle. This can be used with either the foot
pedal or the torch switch functions. For pedal use, however, set Start Amps at the minimum setting unless arc starting is difcult
due to a large tungsten, or poorly prepped weld surface.
Section 2 Setup Guide
UNDERSTANDING AC TIG FUNCTIONS