Lincoln Electric IM348 AC-225-GLM - Manual (Page 18)

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Use the thumb control on the arc torch to rotate the carbons
until they touch. Start the arc by reversing the thumb con-
trol setting to spread the carbons 1/16 to 3/16" apart. As the
carbons burn away use the thumb control to maintain the
desired arc. When the proper arc can no longer be main-
tained, turn the welder off and readjust the carbon stickout.
A wide, soft, quiet flame gives the best results for most
jobs. When the carbon tips are too close together a small
flame accompanied by a hissing or crackling sound results.
The shape of a good flame is illustrated below. The flame
fans out to form a “fish tail” shape with inner and outer
cone. To heat a crack or a corner, position the flame as illus-
trated.
Heat intensity is controlled by changing the current setting,
by moving the carbons closer together or farther apart, or
by changing the distance between the flame and work.
When the work sets on a metal table, the table absorbs
some of the heat. To avoid high heat loss, the part can be set
of thin metal strips or some insulation.
Removal of Nuts and Bolts: Apply heat with the arc torch
for a few seconds and nuts can be easily turned off.
Heating Heavy Parts
Heavy metal can be heated more rapidly by connecting the
work lead to the work so the arc is between the carbons and
the work as well as between the two carbons. To do this,
connect the lead carbon (the carbon which leads the direc-
tion of travel) to the electrode holder. Connect both the trail
carbon and the work cable to the work or to the welding
table. With this connection, raising the torch reduces the
amount of the arc going to the work thus reducing the heat-
ing. The arc between the carbons and work tends to pit the
surface of the work.
Welding Aluminum Alloys With The
Arc Torch
The need to repair aluminum parts continues to grow.
These repairs can be simply made with an AC welder using
Aluminweld DC coated electrodes as a filler rod and The
Carbon Arc Torch. The arc torch preheats the aluminum
plate, assuring good fusion.
Work Preparation
Here are recommended edge preparations and types of
joints for different thicknesses of base metal. All welds
must be made in the downhand position. Round parts must
be rotated.
0.06"
2.00"