Welding Techniques For The Self-Shielded (Gasless) Fcaw Process - Lincoln Electric REDI-MIG 455 Remote Operating Manual

5.7 Welding Techniques For The Self-
Shielded (Gasless) FCAW Process
Four simple manipulations are of prime importance when
welding. With complete mastery of the four, welding will be
easy. They are as follows:
1. The Correct Welding Position
Figure 3 illustrates the correct welding position for right
handed people. (For left handed people, it is the
opposite.)
Hold the gun (of the gun and cable assembly) in your
right hand and hold the shield with your left hand. (Left
handers simply do the opposite.)
When using the FCAW Process, weld from left to right
(if you are right handed). This enables you to clearly see
what you are doing. (Left handers do the opposite.) Tilt
the gun toward the direction of travel holding the
electrode at an angle as shown in Figure 3.
Figure 3
ARC RAYS can burn
eyes and skin
When using an open arc process, it is necessary to use
correct eye, head and body protection.
Protect yourself and others, read "ARC RAYS can burn" at
the front of this manual.
2. The Correct Way To Strike An Arc
1. Be sure the work clamp makes good electrical
contact to the work.
2. Position gun over joint. End of wire may be lightly
touching the work.
3. Position face shield to protect face and eyes, close
gun trigger, and begin welding. Hold the gun so that
the contact tip to work distance is about 10 - 12 mm.
4. To stop welding, release the gun trigger and pull the
gun away from the work after the arc goes out.
5. A ball may form at the tip end of the wire after
welding. For easier restrikes the ball may be
removed by feeding out a few inches of wire and
simply bending the wire back and forth until it breaks
off.
6. When no more welding is to be done, turn off the
machine.
3. The Correct Electrical Stickout (ESO)
The electrical stickout (ESO) is the distance from the
end of the contact tip to the end of the wire.
See Figure 4.
Once the arc has been established, maintaining the
correct ESO becomes extremely important. The ESO
should be approximately 10 - 12 mm long.
Figure 4
Contact Tip
Wire Electrode
IMA 603
Figure 5
Figure 6
10 - 12 mm
Electrical Stickout
(ESO)
REDI-MIG 455 Remote
The easiest way to tell whether the ESO is the correct
length is by listening to its sound. The correct ESO has
a distinctive "crackling" sound, very much like eggs
frying in a pan. A long ESO has a hollow, blowing or
hissing sound. If the ESO is too short, you may stick the
contact tip or nozzle to the weld puddle and/or fuse the
wire to the contact tip.
4. The Correct Welding Speed
The important thing to watch while welding is the puddle
of molten metal right behind the arc. See Figure 5. Do
not watch the arc itself. It is the appearance of the
puddle and the ridge where the molten puddle solidifies
that indicates correct welding speed. The ridge should
be approximately 10 mm behind the wire electrode.
Most beginners tend to weld too fast, resulting in a thin
uneven, "wormy" looking bead. They are not watching
the molten metal.
Solidifying ridge
Helpful Hints
1. For general welding, it is not necessary to weave the
arc, neither forward or backward nor sideways. Weld
along at a steady pace. You will find it easier.
2. When welding on thin plate, you will find that you will
have to increase the welding speed, whereas when
welding on heavy plate, it is necessary to go more
slowly in order to get good penetration.
3. When welding sheet metal 1.6 mm and lighter, heat
buildup may cause part warpage and burn through. One
way to eliminate these problems is to use the back-
stepping method illustrated in Figure 6.
First weld from A to B; then from C to A; then
from D to C; then from E to D, and so on.
B A C
Back-Stepping
Practice
The best way of getting practice in the four skills that
enable you to maintain:
1. Correct welding position
2. Correct way to strike an arc
3. Correct electrical stickout
4. Correct welding speed is to perform the following
exercise.
Molten puddle
D E
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