Learning to weld with an arc welder centers on mastering the preparation steps and the technique for establishing the welding arc itself. This process creates the heat needed to melt and join metal pieces.
Preparing for Arc Welding
Before you can strike an arc, proper preparation is crucial for a strong weld.
- Clean the Metal Surface: You must clean the metal surface to be welded. This involves removing rust, paint, grease, or any other contaminants. A clean surface ensures good electrical contact and prevents impurities from weakening the weld.
- Set the Correct Amperage: Next, set your electrode to the correct amperage for the thickness of the metal you are welding. The amperage controls the heat of the arc, which needs to be matched to the metal thickness for proper penetration and fusion. Thicker metals generally require higher amperage.
Striking and Establishing the Arc
Once the metal is prepared and the machine is set, the key action is establishing the arc.
- Holding the Electrode: Hold the electrode holder at a 90-degree angle to the metal surface. While this is the initial positioning for striking, the angle will typically be adjusted slightly (often to 10-15 degrees from vertical in the direction of travel) once welding begins to control the weld puddle.
- Striking the Arc: The arc is initiated by briefly touching the electrode to the metal. Strike the electrode against the metal surface with a quick motion, then pull it back about 1/8 inch to establish an arc. This motion is similar to striking a match. Pulling back quickly creates the small gap needed for the electrical current to jump, forming the plasma arc that generates intense heat.
Once the arc is established at the correct distance (usually about the diameter of the electrode), the heat melts the base metal and the electrode, creating a molten weld puddle. Welding then proceeds by carefully moving the electrode along the joint while maintaining the arc and controlling the puddle.
