the point where the crackling sound of the arc just disappears. With this
welding control system, the dial setting affects arc length by changing
electrode wire feed speed at a given welding power supply current setting.
Increasing the setting of the dial will shorten the arc.
7.
To stop the weld, release the trigger. Do not whip the gun away from the
work before releasing the trigger to break the arc as this will cause
excessive wire stick-out. CAUTION: Breaking the arc manually (by whipping
the gun away from the work with the trigger depressed) will cause a current
surge to the wire feed motor. Repeated practice will result in a blown
motor fuse (1 Amp) and can cause motor burn out.
Wire Current Ranges
The following is a table of approximate current and voltage ranges of various
types and sizes of wire for spray transfer operation:
Welding
Arc
Wire
Diameter
Current Range
Voltage Range
Alloy
Aluminum
AL-1100 & 4043
3/64
130-225
19-23
.040
AL-11OO & 4043
Aluminum
120-210
18-23
AL-5154, 5254 &
3/64
130-225
19-23
Aluminum
5356
Welding Techniques
After the operator has found the desired current and arc length settings for
a particular joint, it is still necessary that he observes some elementary
principles of technique.
1.
Nozzle Spacing
In general, the gas nozzle should be kept as close to the work as is
practical. In most cases, a distance of 3/8 - 5/8 of an inch is correct.
If the nozzle is too close a burn-back may result. With the nozzle too
far away, a poor weld results.
Gun Angle
2.
Best cleaning action of the weld area is obtained and porosity-free welds
made by using a forehand technique. For example, a horizontal fillet
between two plates at a 90 angle is best made by holding the gun at an
angle of 40 to 50 with the horizontal and 20 to 25 forehand angle. A
right-handed welder will then weld from right to left on a horizontal
fillet weld with the nozzle pointed slightly toward the direction of travel.
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