Lincoln Electric IM348 AC-225-GLM - Manual (Page 19)

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Joints
Welding Procedures
1. Use the recommended AC currents and carbon sizes list-
ed in the Table on page 17. A headshield is required.
2. Use a l/8" ‘Aluminweld’ coated electrode as a filler rod.
Hold it in the left hand (for right-handed people).
3. Hold the arc torch in your right hand and start the arc by
shorting the carbons together and adjusting them to a
1/16" gap.
4. Hold the arc torch as shown here. Hold your eyes right
over the arc torch looking in between the two carbons.
5. Play the arc 3" to 4" up and down the joint at the start.
This preheat helps to give a smoother bead and an easi-
er start when the filler rod is applied.
6. Move the torch to the beginning of the joint (right-hand-
ed people should begin at the right and move left).
7. Place the tip of the electrode in the arc. If the coating
melts off and flows easily into the joint, the metal is hot
enough to start welding.
8. Let a droplet of the filler rod melt and fuse into the
joints.
9. Watch the molten puddle. Add more filler metal by mov-
ing the end of the rod in and out of the arc as the right
hand moves the arc torch slowly along the joint.
Practice
When you first try to weld with these procedures, you may
have a tendency to burn through. Therefore, a few minutes
practice before working on the parts to be welded is rec-
ommended. Use scrap material about as thick as the part
you are going to weld. Practice the technique to get the feel
of the arc.
Brazing
The techniques for brazing with an arc torch are very much
like the ones used for gas brazing. Only enough heat is
needed to melt the filler metal and to raise the parts to be
brazed to the melting temperature of the filler metal — usu-
ally slightly over 1,000°F. A good brazed joint is assured
when the filler metal flows into the joint and adheres even-
ly to the surfaces. Use only enough filler metal to make a
smooth joint. Use standard gas brazing rod and flux .
Heat the end of the brazing rod and dip it into the flux. The
flux will stick to the hot rod. Play the arc back and forth a
short distance along the seam when the right temperature is
reached. Apply flux as needed and melt off brazing rod to
fill the seam. Move along the seam until the job is com-
plete.
If the part being brazed does not get hot enough, increase
the current or hold the torch closer to the work. Whenever
possible, have the joint horizontal to secure best flow of
molten filler rod.
Soldering
The arc torch can be used to solder copper piping and other
copper, tinned and galvanized parts. Best results are
obtained with overlapping pieces. Clean the surfaces to be
soldered and cover them with soldering flux to prevent oxi-
dation and to speed soldering. Acid core solder produces
good results.
The best soldering can be done on the lowest current tap of
the welder. Use approximately 1/4" diameter carbon and
make certain to bring it into firm contact with the piece to
be soldered to avoid arcing. Simply play the arc on the area
to be soldered and feed solder into the joint as it reaches
proper temperature. After the soldering is completed, the
carbon must be removed quickly to prevent arcing. Never
use so much heat that the solder boils.
Heating, Bending and Straightening
Choose the carbon size and current setting depending upon
the thickness of the metal to be heated. Play the arc over the
section to be heated until the desired temperature is
reached. For bending this is usually a dull red color on ordi-
nary mild steels.
Do not hold the carbons too close to the work. Arcing the
surface increases the tendency for the base metal to crack
when the bending is done.
Carbon Arc Torch Maintenance
The handle is held together with a screw and spring lock
washer to give just the right friction on the electrode shafts.
If the handle is removed for any reason, the screw at the
front of the handle should be turned up snugly and then
backed of 1/2 turn to give the proper friction.
Occasionally the screws in the copper jaws will bind, so it
will be advantageous to lubricate the threads with graphite
grease and work the grease well into the threaded jaw.
SELECTING ELECTRODES
Which electrode is best for the particular job . . . how do
you use it? These are important questions because the cost,
quality, and appearance of your work depends on proper
electrode selection and application. MILD STEEL ELEC-
TRODES may be classified into the following groups:
Out-of-Position Group (E6011)
This group includes electrodes which have a snappy, deep
penetrating arc and fast freezing deposits.