7
WG3020
Changing Wire Sizes
DRIVE ROLLER
Included with this welder are three
drive rollers - 0.030” - 0.035” (0.8 mm -
0.9 mm) serrated groove roller for flux
core wire (installed at the factory),
0.024” (0.6 mm) smooth groove roller
for MIG wire and 0.030” - 0.035” (0.8
mm - 0.9 mm) smooth groove roller for
MIG wire. The sizes are stamped on the
rollers. Match the size and type of the
roller to the size and type of welding
wire used. Remove the two screws
securing the roller cover and change
rollers as required. Replace the roller
cover and attach with the two screws.
Welding Guidelines
General
This line of welding machines can
utilize the Flux Cored Arc Welding
(Gasless) process or the Gas Metal Arc
Welding (MIG) process. The weld must
be protected (shielded) from
contaminates in the air while it is
molten. The gasless process uses a
tubular wire with a flux material inside.
The flux creates a shielding gas when
melted. The MIG process uses inert gas
to shield the weld while molten.
When current is produced by a
transformer (welding machine) and
flows through the circuit to the weld
wire, an arc is formed between the end
of the weld wire and the work piece.
This arc melts the wire and the work
piece. The melted metal of the weld
wire flows into the molten crater and
forms a bond with the work piece as
shown (Figure 8).
Arc Welding Basics
Five basic techniques affect weld
quality. These are: wire selection, heat
setting, weld angle, wire speed, and
travel speed. An understanding of
these techniques is necessary for
effective welds.
HEAT SETTING
The correct heat involves the adjust-
ment of the welding machine to the
required setting. Heat or voltage is
regulated by a switch on the welder.
The heat setting used depends on the
size (diameter) and type of wire,
position of the weld, and the thickness
of the work piece. Consult specif-
ications listed on the welder. It is
suggested that the welder practice with
scrap metal to adjust settings and
compare welds with Figure 10.
WIRE TYPE AND SIZE
The correct choice of wire type involves
a variety of factors, such as welding
position, work piece material type,
thickness and condition of surface to be
welded. The American Welding Society,
AWS, has set up certain requirements
for each type of wire.
FLUX-CORE WIRE
E
-
7 0 T
-
GS
Weld strength, times
10,000 psi
Welding positions (0
for flat or horizontal,
1 for any position)
Tubular flux core wire
Flux type
AWS E71T-GS or E71T-11 is
recommended for this welder.
SOLID WIRE
ER
-
70 S
-
6
Weld strength, times
1,000 psi
Solid wire
Wire composition
ER-70S6 is recommended for this
welder.
WELD ANGLE
Weld angle is the angle at which the
nozzle is held during the welding
process. Using the correct angle
ensures proper penetration and bead
formation. As different welding
positions and weld joints become
necessary, nozzle angle becomes an
increasingly important factor in
Maintenance
(Continued)
Slag
Weld
Wire
Flux
(Gasless
only)
Work Piece
Shielding
Gas
Contact
Tip
Crater
Nozzle
Figure 8 - Weld Components
CONTACT TIPS
Included with this welder are three
contact tips - 0.024” (0.6 mm), 0.030”
(0.8 mm) and 0.035” (0.9 mm) (installed
at the factory). The sizes are stamped
on the contact tips. Match the size of
the contact tip to the size of the
welding wire used. Unscrew the nozzle,
then unscrew the contact tip. Screw the
required contact tip into the diffuser,
then screw the nozzle onto the
diffuser.
ALUMINUM WIRE
When welding aluminum, the above
instructions must be followed without
exception. Also, do not over tighten
the tension screw. Over tightening will
cause the soft aluminum wire to be
compressed into an oval cross-section.
Call (800) 746-5641
for replacement parts.
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This will create inconsistent drag in the
wire liner. A consistent wire feed rate is
very crucial to successful welding of
aluminum. Apply only enough tension
to keep the wire from slipping on the
drive roller. Do not use the serrated
drive roller for aluminum wire. The
serration in this roller will deform the
soft aluminum wire, causing
inconsistent drag in the wire liner.
