Welding Techniques - Matco Tools MP200STDVI Owner's Manual

4.1. When proper rod is used:
4.1.a. The bead will lay smoothly over the work without ragged edges
4.1.b. The base metal puddle will be as deep as the bead that rises above it
4.1.c. The welding operation will make a crackling sound similar to the sound of eggs frying
4.2. When a rod too small is used:
4.2. a. The bead will be high and irregular
4.2. b. The arc will be difficult to maintain
4.3. When the rod is too large:
4.3. a. The arc will burn through light metals
4.3. b. The bead will undercut the work
4.3. c. The bead will be flat and porous
4.3. d. Rod may freeze or stick to work piece
Note: Rate of travel over the work also affects the weld. To ensure proper penetration and enough
deposit of rod, the arc must be moved slowly and evenly along the weld seam.
5. SETTING THE AMPERAGE CONTROL
The welder has current control that is infinitely adjustable within its range. It is capable of welding
with electrodes up to 3/32" diameter. There is no golden rule that determines the exact amperage
required for every situation. It is best to practice your welds on scrap metal which matches the
metals you intend to work with to determine correct setting for your job. The electrode type and the
thickness of the work piece metal determine the amount of heat needed in the welding process.
Heavier and thicker metals require more voltage (amperage), whereas lighter and thinner metals
require less voltage (amperage). Consult the welding electrode packaging for recommended
welding amperage range.

6. 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 that the appearance of your practice welds are
of good appearance and free of slag or gas inclusions.
6.1 Holding the electrode
The best way to grip the electrode holder is the way that feels most comfortable to you. Position the
electrode to the work piece when striking the initial arc, it may be necessary to hold the electrode
perpendicular to the work piece. Once the arc is started, the angle of the electrode in relation to the
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