Stroke arc induction method

The scratch-and-scratch arc ignition method is the most commonly used arc ignition method in shielded metal arc welding (SMAW). Simply put, it's like striking a match; the welding rod is lightly scratched across the workpiece surface to create a spark that ignites the arc.

Operating Method:
* **Alignment:** Align the end of the welding rod with the starting point of the weld.
* **Scratch:** Using your wrist, scratch the welding rod horizontally across the workpiece surface for 10-30 mm, like striking a match.
* **Lift:** Immediately after scratching, lift the welding rod vertically 2-4 mm, maintaining this distance to allow the arc to burn stably.

**Precautions:**
* **Quick Action:** Lift the welding rod decisively; too slow a movement can cause it to stick to the workpiece.
* **Correct Location:** It's best to scratch on the bevel or weld seam, avoiding random scratching on the workpiece surface to prevent damage.

**Handling Sticky Rod:** If the rod sticks, do not pull it off forcefully. Gently shake the welding rod from side to side or disconnect the power supply and allow it to cool before handling.

**Advantages and Disadvantages:**
* **Advantages:** Simple method, easy to learn, and does not require a high degree of cleanliness on the welding rod surface. Disadvantages: If the operator is not skilled, it can easily scratch the workpiece surface and may also remove the electrode coating, affecting the welding quality.

Other Arc Ignition Methods

Besides the scratch method, there are also the direct strike method (impact method) and high-frequency arc ignition and booster arc ignition used in TIG welding. The scratch method is the first choice for beginners because it is simple and easy to learn.