Lincoln Electric PRO 155, Operator'S Manual

Page: 22 / 46

B-9
B-9
LEARNING TO WELD
2. Can I afford the extra expense, space, and lack of
portability required for gas cylinders and gas sup-
ply?
3. Do I require clean, finished-looking welds?
If you have answered yes to all the above questions
GMAW may be the process for you. If you have
answered no to any of the above questions, then you
should consider using the FCAW process.
For FCAW (Innershield) Process
1. Do I want simplicity and portability?
2. Will welding be performed outdoors or under windy
conditions?
3. Do I require good all position welding capability?
4. Will most welding be performed on 16 gauge and
heavier, somewhat rusty or dirty materials?
5. Weld must be cleaned prior to painting.
COMMON METALS
Most metals found around the farm, small shop or
home are low carbon steel, sometimes referred to as
mild steel. Typical items made with this type of steel
include most sheet metal, plate, pipe and rolled
shapes such as channels and angle irons. This type of
steel can usually be easily welded without special pre-
cautions. Some steels, however, contain higher car-
bon levels or other alloys and are more difficult to
weld. Basically, if a magnet sticks to the metal and
you can easily cut the metal with a file, chances are
good that the metal is mild steel and that you will be
able to weld the material. In addition, aluminum and
stainless steel can be welded using the K664-1
Aluminum Welding Kit. For further information on iden-
tifying various types of steels and other metals, and
for proper procedures for welding them, we again sug-
gest you purchase a copy of
“ New Lessons in Arc
Welding ” .
Regardless of the type of metal being welded, in order
to get a quality weld, it is important that the metal is
free of oil, paint, rust or other contaminants.
MACHINE SET UP FOR THE
SELF-SHIELDED FCAW PROCESS
1. See PROCESS GUIDELINES in the OPERATION
section for selection of welding wire and shielding
gas, and for range of metal thicknesses that can be
welded.
2. See the Application Guide on the inside of wire
feed section door for information on setting the
controls.
3. 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 ‘’ olo. ’’
4. Check that the polarity is correct for the welding
wire being used. Set the polarity for DC( – ) when
welding with NR-211-MP Innershield electrode.
See Work Cable Installation in the INSTALLATION
section for instructions on changing polarity.
5. When using Innershield electrode, the gasless noz-
zle may be used instead of a gas nozzle to improve
visibility of the arc.
6. 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 this manual.
WELDING TECHNIQUES FOR THE SELF-
SHIELDED 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 B.11 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 B.11.
PRO 155