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OPERATING THE WELDER (MMA)

The consumable electrode is connected to a high amperage low voltage supply which

creates an electric arc between the electrode and the workpiece.

The most difficult aspect of the arc welding process, particularly for beginners, is that

of striking an arc. We strongly recommend that you practice on some pieces of scrap

metal to get the feel of the operation before you start an actual welding job.

1. Holding the welding mask close-up to your face, give a short stroke with the

electrode on the workpiece. As soon as the arc is primed, withdraw the electrode

from the workpiece to leave a gap. The current will flow across the gap with a

crackling noise and a brilliant arc. Continue to weld in one direction, maintaining

the small gap as you go.

2. As soon as the arc is struck, maintain a distance from the workpiece equal to the

diameter of the electrode. Keep this distance as constant as possible for the

duration of the weld. As you advance along the workpiece the angle of the

electrode must be maintained at between 20º and 30º.

NOTE: When you prime the arc be sure to withdraw the electrode swiftly to

leave the gap, otherwise the electrode will weld itself to the workpiece.

If this occurs give the electrode a short sharp jerk to free it and, if

necessary, prime the arc again. If you cannot free the electrode, switch

the machine off immediately and free it. Take care the electrode will get

red hot very quickly and will be capable of burning through welding

gloves.

3. At the finish of the weld, bring the end of the electrode backward in order to fill

the weld crater and then quickly lift the electrode from the weld pool to extinguish

the arc.

4. Inspect the job carefully. Any slag forming on the surface should be chipped away

with a chipping hammer or pick. ALWAYS wear your safety goggles when chipping

away slag.

WARNING: WHEN WELDING ALWAYS ENSURE THERE IS ADEQUATE

VENTILATION IN THE WORK AREA DUE TO TOXIC FUMES.

WARNING: DO NOT STRIKE THE ELECTRODE ON THE WORKPIECE,

AS THIS MAY DAMAGE THE ELECTRODE.

WARNING: WELDING ARCS PRODUCE HARMFUL UV/IR LIGHT

WHICH CAN SERIOUSLY DAMAGE YOUR EYES. ALWAYS USE A

WELDING FACE-SHIELD WITH A SUITABLE FILTER THAT CONFORMS

TO CURRENT STANDARDS.

WARNING: PROTECT BYSTANDERS BY USING WELDING SCREENS.