Machine Set Up For The Gmaw (Mig) Process; The Correct Welding Position; The Correct Way To Strike An Arc - Lincoln Electric LTW1 Manual De Instrucciones

LEARNING TO WELD
MACHINE SET UP FOR THE
GMAW (MIG) PROCESS
1. See APPLICATION CHART in the OPERATION section
or Application Chart on the inside of wire feed section
door for selection of welding wire and shielding gas,
and for range of metal thicknesses that can be welded.
These materials will also assist in setting the proper
controls, drive roll orientation and output polarity.
2 Set the "Voltage" and "Wire Speed" controls to the
settings suggested on the Application Guide for the
welding wire and base metal thickness being used. The
voltage control is marked "V" and the wire feed speed
is marked with the icon "olo.''
3 Check that the polarity is correct for the welding wire
being used. Set the polarity for DC(+) when welding with
the GMAW (MIG) process. See INSTALLATION section
of the Operators Manual for instructions for changing
polarity.
4. Check that the gas nozzle and proper size liner and
contact tip are being used and that the gas supply is
turned on. If adjustable, set for 30 to 40 cubic feet per
hour (7 to 10 l/min..) under normal conditions. Increase
to as high as 45 CFH (17 I/min.) under drafty (slightly
windy) conditions.
5. Connect work clamp to metal to be welded. Work
clamp MUST make good electrical contact to the work
piece. The work piece must also be grounded as stated
in the "Arc Welding Safety Precautions" at the
beginning of the Instruction Manual which is supplied
with each welder.
WELDING TECHNIQUES
FOR THE GMAW (MIG)
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 17 illustrates the correct welding position for right handed
people. (For left handed people, it is the opposite.)
When GMAW (MIG) welding on sheet metal, it is important to use the
"forehand" push technique.
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.)
Figure 17
Push
When using the GMAW process on light gauge material, weld from
right to left (if you are right handed). This results in a colder weld and
has less tendency for burn through.

2.The Correct Way To Strike An Arc

WARNING
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 the
Operators Manual supplied with
welder.(ANSI Z.49.1-88)
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 3/8" to 1/2"
(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 cutting off the end
of the wire with wire cutters.
6. When no more welding is to be done, close the valve on
the gas cylinder, momentarily operate the gun trigger to
release gas pressure, then turn off the machine.
9
15°-20°