Century IM998 Welding System User Manual


 
B-4
OPERATION
B-4
4. Immediately after striking the arc try to maintain a
distance from the workpiece that is equivalent to
the diameter of the electrode used. Maintain this
distance as constantly as possible during the weld.
Whenever possible, weld from left to right (if right-
handed). Hold the electrode at a slight angle as
shown. (See Figure B.5)
FIGURE B.5
5. As the electrode burns off the electrode must be fed
to the work to maintain correct arc length. The easi-
est way to tell whether the arc has the correct
length is by listening to its sound. A nice, short arc
has a distinctive, “crackling” sound, very much like
eggs frying in a pan. The incorrect, long arc has a
hollow, blowing or hissing sound.
6. The important thing to watch while welding is the
puddle of molten metal right behind the arc. Do
NOT watch the arc itself. It is the appearance of the
puddle and the ridge where the molten puddle
solidifies that indicate correct welding speed. The
ridge should be approximately 3/8" (9.5mm) behind
the electrode. (See Figure B.6)
FIGURE B.6
Most beginners tend to weld too fast, resulting in a
thin, uneven, “wormy” looking bead. They are not
watching the molten metal.
IMPORTANT: For general welding it is not necessary
to weave the arc; neither forwards and backwards nor
sideways. Weld along at a steady pace. You will find it
easier. NOTE: When welding on thin plate, you will
find that you will have to increase the welding speed,
whereas when welding on heavy plate, it is necessary
to go more slowly in order to get good penetration.
7. Once the electrode is burned down move the elec-
trode quickly from the weld to extinguish the arc.
8. Turn the machine off and remove the stub by open-
ing the jaws of the electrode holder and insert a
new electrode.
Note: The welded work piece and electrode stub are
hot after welding. Allow them to cool down
before touching or use pliers to move. Always
make sure the welder is turned off before set-
ting down the Electrode Holder.
INVERTER ARC™ 120