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Operation
Welding Preparation
Factors to Consider for Best MIG Welding Results
An important factor in making a satisfactory weld is preparation. This includes studying the process and equipment
and practicing welding before attempting to weld finished product. An organized, safe, comfortable, and well-lit work
area should be prepared for the operator. The work area should specifically be free of all flammables with both a fire
extinguisher and a bucket of sand available.
To properly prepare for welding with your new spool gun, it is necessary to:
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Read the safety precautions at the front of this manual.
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Prepare an organized, well-lit work area.
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Provide protection for the eyes and skin of the operator and bystanders.
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Attach the ground clamp to the bare metal to be welded, making sure of good contact.
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Make sure that the wire-roller groove corresponds to the diameter of wire being used.
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Plug the machine into a suitable outlet.
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Completely open the gas cylinder valve. Adjust the gas pressure regulator to the correct flow rate.
EXPOSURE TO A WELDING ARC IS EXTREMELY HARMFUL TO THE EYES AND SKIN. PROLONGED
EXPOSURE TO A WELDING ARC CAN CAUSE BLINDNESS AND BURNS. NEVER STRIKE AN ARC OR
BEGIN WELDING UNLESS YOU ARE ADEQUATELY PROTECTED. WEAR FIRE RESISTANT WELDING
GLOVES, HEAVY LONG-SLEEVED SHIRT, CUFF-LESS PANTS; HIGH TOPPED SHOES AND A WELDING
HELMET.
Some experience is required to adjust and use a MIG welder. In MIG welding, two parameters are fundamental: the
welding voltage and the wire feed speed. The resulting welding current is a result of these two settings but is more directly
related to the wire feed speed.
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Set the voltage (LEFT KNOB) and wire feed speed (RIGHT KNOB) to positions suitable for the thickness of the material
to be welded. Welding current varies in relationship to wire feed speed. For low wire feed speed (RIGHT KNOB),
welding current output will be low. Turning the wire feed speed control clockwise will result in increased wire feed
speed and welding current. Welding voltage should be adjusted to match the wire feed speed/welding current.
Progressively select higher voltage positions when increasing wire speed.
Increasing welding voltage leads to a longer arc (without substantially affecting the current). Conversely, a decreased
welding voltage results in a shorter arc (the current again is not substantially changed). A change in wire diameter results
in changed parameters. A larger diameter wire will draw a higher current than a smaller diameter wire at the same wire
feed speed. If certain limits are exceeded, a satisfactory weld cannot be obtained. These are:
1.
Feeding wire too fast (too high speed with regard to the welding voltage) results in pulsing within the gun. This is
