Stick (Mmaw) Basic Welding Technique; Striking The Arc - Ryobi MMA-140 Owner's Operating Manual

STICK (MMAW) BASIC WELDING TECHNIQUE

A WORD TO BEGINNERS
For those who have not yet done any welding, the
simplest way to commence is to run beads on a
piece of scrap plate. Use mild steel plate about
6.0mm thick and a 3.2mm electrode. Clean any
paint, loose scale or grease off the plate and set it
firmly on the work bench so that welding can be
carried out in the downhand position. Make sure
that the work clamp is making good electrical
contact with the work, either directly or through the
work table. For light gauge material, always clamp
the work lead directly to the job, otherwise a poor
circuit will probably result.
THE WELDER
Place yourself in a comfortable position before
beginning to weld. Get a seat of suitable height and
do as much work as possible sitting down. Don't
tense your body. Relax and you will find that the job
becomes much easier. Wear a leather apron and
gauntlets. This will protect you from being burnt or
sparks setting alight to your clothes.
Place the work so that the direction of welding is
across, rather than to or from, your body. The
electrode holder lead should be clear of any
obstruction so that you can move your arm freely
along as the electrode burns down. If the lead is
slung over your shoulder, it allows greater freedom
of movement and takes a lot of weight off your
hand. Be sure the insulation on your cable and
electrode holder is not faulty, otherwise you are
risking an electric shock.

STRIKING THE ARC

Holding a face mask in front of your face stroke the
electrode point on the workpiece as if striking a
match.
Maintain a steady gap between the end of the
electrode and the workpiece of approximately 2mm
(Fig.7).
Maintain this distance as constantly as possible
during the weld remember that the angle of the
electrode to the work piece must be 20-30° (Fig.8).
Do not hit the electrode on the workpiece as this
may damage the electrode. Withdraw with a clean
movement at the end of the welding run.
Note: This is the most difficult aspect for most
beginners. It is recommended that you practice on
some scrap material in order to get a feel of the
operation.
If the electrode is not withdrawn quickly enough
once the arc is primed, there is a possibility that the
electrode will weld itself to the workpiece. Should
this happen, give it a sharp tug to free it, and try
again. If this fails to free it, turn off the machine
immediately as it will quickly overheat.
If you withdraw the electrode too far once the arc is
primed, you will lose the arc and have to try again.
Inspect the job carefully. With a correct
combination of electrode size and current setting
the area of weld should be complete fusion of the
electrode and parent metal/s. Any slag which forms
on the surface should be chipped away with the
pick/brush supplied.
If the resultant weld looks messy and irregular, this
is an indication of porosity or slag contamination,
and you have almost certainly failed to achieve the
correct combination. This is a common problem, so
do not worry as practice will quickly cure this.
17
2mm
Fig. 7
20º-30º
Fig. 8