
14
give the operator good results, there is
most likely a problem unrelated to wire
tension present. For example, a bad
contact tip, a bad liner, a defective
welding gun, etc. can cause wire not to
feed smoothly. When welding flux-cored
wire, the tension should be set lower than
2. If flux-cored wire is being fed through
a wire feeder with too much tension, the
tubular flux-cored wire will deform and
its shape will change; the wire will
become oblong and too big to fit through
the contact tip. Improper electrical
contact, poor weld quality, burned tips,
and other issues will follow. Also, over-
tightened drive roll tension and deformed
wire will cause metal particles to separate
from the wire. Those particles will, over
time (sometimes a very short time such
as after welding only several pounds of
wire), deposit themselves in the liner as
the wire is transported through the gun,
ultimately clogging the liner, rendering it
useless. When welding aluminum, the
drive roll tension should be less than 1.
This minimizes the chances of the wire
birds nesting (Note: If there is burn back
or another issue that jams the wire feed,
the setting should be so low that the drive
rolls slip on the wire rather than continue
to feed, which will result in birds
nesting).
Use contact tips that match the diameter
of the wire selected. For example, use
.030” contact tips with .030” wire, use
.035” contact tips with .035” wire, and so
on. Follow these instructions for all wire
types, no matter the metal or alloy.
However, on aluminum wire, the use of
CuCrZr contact tips is strongly
recommended. If CuCrZr tips are not
available, standard tips can be used, but
the tip size has to be .005” larger. For
example, .035”aluminum wire would
require a standard .040”tip, and 3/64”
aluminum wire would require a standard
.052”tip. (Note: Using standard tips
when welding aluminum results in
shorter tip life and limited performance).
Use the correct polarity. Most MIG wires
are welded DCEP (electrode positive),
and there are very few exceptions to this
rule (Gas-less flux-cored wire and some
specialty hard-surfacing wires are
exceptions). If in doubt, please consult
the data sheetthat came with the wire, the
box the wire came in, or contact the
distributor you bought the wire from.
Use the correct welding gun. For welding
stainless steel wire or aluminum wire, a
cylindrical gas nozzle provides better gas
coverage.
If welding in synergic or pulse mode,
chose the correct material thickness
(reduce the material thickness if you need
to fill big gaps or if the material you are
welding is very hot) and observe the wire
manufacturer’s recommended CTDW.
MIG 2T
Press and release Select Mode button Aas many
times as needed until the green LED next to 2T
illuminates. If welding in the manual mode is
desired, press and release button Btwice quickly.
The machine is now in manual mode (Fig. 11).
Turn encoder Fto set the wire feed speed, and
turn encoder Gto set the voltage.
If welding with synergic or pulse programs is
desired, press and release button Bonce and the
program list is displayed (Fig. 12).