Würth TIG 200LCD AC/DC Originalbetriebsanleitung Seite 27

3.6 Setting the adequate amperage
Your welder is capable of welding with 2.5mm,
3.2mm and 4mm electrodes.
There is no golden rule that determines the exact
amperage required for every particular situation. It
is best to practice your welds on scrap metal which
matches the metals you intend to work with in order
to determine correct settings for your job. The elec-
trode type and the thickness of the metal workpiece
define the amount of heat needed in the welding
process. Heavier and thicker metals require more cur-
rent (amperage), whereas lighter and thinner metals
require less current (amperage).
3.7 Welding techniques
The best way to teach yourself how to weld is with
short periods of practice at regular intervals. All
practice welds should be done on scrap metal that
can be discarded. Do not attempt to make any
repairs on valuable equipment until you are satisfied
with yourself and your practice welds are of good
appearance and free of slag or gas inclusions.
3.7.1 Holding the electrode
The best way to grip the electrode holder is the way
that feels most comfortable to you. To position the
electrode on a workpiece when striking the initial
arc, it is necessary to hold the electrode perpendic-
ular to the workpiece. Once the arc is started the
angle of the electrode in relation to the workpiece
should be between 10 and 30 degrees. This will
allow good weld penetration, with minimal spatter.
3.7.2 Striking the arc
WARNING!
EXPOSURE TO A WELDING ARC IS EXTREMELY
HARMFUL TO THE EYES AND SKIN.
• Never strike an arc or begin welding until you
have adequate protection.
• Wear flameproof welding gloves, heavy long-
sleeved shirt, cuffless trousers, high-topped shoes
and a welding helmet or shield.
Scratch the work piece with the end of electrode to
start arc and then raise it quickly to about 3 mm
gap between the rod and the workpiece. Please
observe the following picture:
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It is important that the gap is maintained during the
welding process and it should be neither too wide
or too narrow. If it is too narrow, the rod will stick to
the workpiece. If it is too wide, the arc will be extin-
guished. It takes a a lot of practice to maintain the
gap. Beginners may usually get sticking or arc extin-
guishing. When the rod sticks to the workpiece, gen-
tly rock it back and forth to separate it from the work-
piece. If you don't, the short circuit occurs, which
leads to welder overload. A good arc is accompa-
nied by a crisp, cracking sound. The sound is similar
to that made when frying eggs. To lay a weld bead,
only 2 movements are required; downwards and in
direction of the weld to be laid, as shown in the fol-
lowing picture:
3.7.3 Types of weld beads
The following paragraphs discuss the most com-
monly used arc welding beads.
The stringer bead is formed when electrode is
traveling in a straight line while kept centered over
the weld joint.
The weave bead is used when you want to
deposit metal over a wider space which wouldn't be
possible using a stringer bead (without transfer oscil-
lation). It is made by weaving electrode from side
to side with slight hesitation at the end of each oscil-
lation while moving it longitudinally. That is the best
way to improve weld penetration.