Forney MIG 180FI, Руководство по эксплуатации

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for a given heat setting by selecting hugher or
lower wire speed settings. Repeat this tune-in
procedure if you select a new heat setting, a
different diameter wire, or a different type of
welding wire.
LEARNING TO WELD
MIG (GMAW) welding is the process of unit-
ing metallic parts by heating and allowing the
metals to flow together through the use of an
electrical arc. The electrical arc is created
between a continuous consumable wire elec-
trode (the welding wire) and the work piece.
An inert shielding gas is used to protect the
weld puddle from contamination and
enhance the welding capabilities of the elec-
trical arc.
Whether you have welded before or not, it is
important that you become familiar with your
new welder, its controls, and the results
achieved at different settings. We strongly
recommend that you practice with your new
welder on scrap metal trying different heat
settings, base metal thicknesses, and welding
positions for each type and size of wire you
will be using. By doing this you will gain a feel
for how changes in these welding variables
affect the weld.
Of course, if you have not welded before,
you will need to develop welding skills and
techniques as well.
The self-taught welder learns through a
process of trial and error. The best way to
teach yourself how to weld is with short peri-
ods of practice at regular intervals. All prac-
tice welds should be done on scrap metal
that can be discarded. Do not attempt to
make any repairs on valuable equipment
until you have satisfied yourself that your
practice welds are of good appearance and
free of slag or gas inclusions. What you fail
to learn through practice will be learned
through mistakes and re-welds later on.
HOLDING THE GUN
The best way to hold the welding gun is the
way that feels most comfortable to you.
While practicing to use your new welder,
experiment holding the gun in different posi-
tions until you find the one that seems to
work best for you. Refer to WELDING POSI-
TIONS - p.21)
Position the Gun to the Work Piece There
are two angles of the gun nozzle in relation
to the work piece that must be con- sidered
when welding.
1. Angle A (Figure 9) can be varied, but in
most cases the optimum angle will be 60
degrees. The point at which the gun han-
dle is parallel to the work piece. If angle
A is increased, penetration will increase.
If angle A is decreased, penetration will
decrease also.
Angle A
Figure 9. Gun Position, Angle A
2. Angle B (Figure 10) can be varied for two
reasons: to improve the ability to see the
arc in relation to the weld puddle and to
direct the force of the arc.
Angle B
Figure 10. Gun Position, Angle B
The force of the welding arc follows a
straight line out of the end of the nozzle.
If angle B is changed, so will the direction of
arc force and the point at which penetration
will be concentrated.
On a butt weld joint, the only reason to vary
angle B from perpendicular (straight up) to
the work piece would be to improve visibility
of the weld puddle. In this case, angle B can
be varied anywhere from zero to 45 degrees
with 30 degrees working about the best.