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Key principle for beginners: In welding, man, machine, material, method, and environment are all important, but operational skills come first. The integration of hand and mind is of utmost importance; one must avoid being impetuous and lacking focus. Stiffness in the right hand is a big no-no; the direction of internal and external rotation should be changed as needed. Advance in three directions simultaneously, and keep the three key points of welding in mind. Pre-weld alignment shall comply with the specifications; the electrodes must be of high quality and dry. There are techniques to ignite an arc; scratching or striking can be chosen as desired. Don’t rush after the arc has ignited; preheating the base material is crucial. Once the temperature rises, perform short arc welding. The molten pool and holes need to be clearly observed; one should not rush forward blindly. When the temperature is high, arc welding should be stopped; when it’s low, welding can be carried out continuously. The arc advances and retreats, with its position changing constantly. The weld positions are different, so the electrode angles are also different. The operator must act quickly when changing electrodes, ensuring a uniform and smooth transition at the joint. To prevent the root from sinking in, push the welding rod forcefully toward the root edge. Pay attention to leaving holes at the ceiling level, as the arc depression angle changes. Hearing the piercing “puff” sound, I feel relieved knowing that the melting has been thorough. Welding is a highly skilled craft; one must read, think deeply, and practice diligently. Appreciate the wonders within; even a small weld holds a world of possibilities. Refined guidelines for welding – Flat welding: Keep two points in mind: listening and observing; the welding parameters should be appropriate. Short arc welding is key; the arc cycle needs to be shortened. The welding speed must be uniform, and the molten pool should remain oval in shape. The arc crater must be filled to ensure sufficient molten iron and prevent shrinkage cavities. Note: 1) “Listening” refers to listening for the sound of the arc passing through; when a \"popping\" sound is heard, it indicates that the arc has broken through the dull edge and created a molten pool. In this case, the arc should be extinguished immediately, otherwise the hole formed will be too large or even cause burning through ； 2) “Observing” means watching the changes in the temperature and shape of the molten pool. The pool temperature and shape determine the width, bead height, and shape of the back weld. The molten pool temperature is too high and the penetration is too large; the back weld is both tall and wide, which is unsightly, and it is prone to burn-through. If the pool temperature is too low and the penetration hole is too small, the root weld often fails to bond properly, or even fails to achieve full penetration. Typically, the molten pool is oval in shape, and it is appropriate for the melt to cover 0.5–1 mm on each side of the groove. Refined mental technique—upward welding: The size of the molten pool should be appropriate, and it is necessary to distinguish between slag and molten metal. Sufficient arc-quenching molten iron must be provided to prevent shrinkage cavities on the back side. The wire movement should be flexible, and the joint formation should be guided by the sound of the arc. Good fusion on both sides of the groove to prevent defects and maintain shape. Note: 1) When welding in the vertical position, due to the effect of gravity, the molten metal tends to flow downward; therefore, it is necessary to control the size of the molten pool ； 2) To prevent the root weld from forming a “bulged” shape, an angle is created between the groove and the weld bead, which may lead to slag inclusion and affect the welding of the filler and cover layers. Therefore, when the electrode reaches both sides of the groove, it must be paused for a suitable period to ensure proper fusion on both sides of the groove. Key tips for transverse and vertical welding: One arc serves two purposes; penetration ensures proper shape formation ； For horizontal welding, use arc extinguishing hooks; for overhead welding, push upwards. Note: 1) “One arc, two purposes”: To achieve the goal of forming welds on both sides from a single welding process, the welding arc must be used on both the front and back sides. Typically, 2/3 of the arc time is spent on the front side, while 1/3 is spent on the back side ； 2) “Perforation for forming”: That is, formation on the back side is possible only when the arc breaks through the blunt edge to create a molten hole ； 3) “Horizontal welding arc extinguishing motion”: During horizontal welding, the electrode is used to initiate an arc on the upper side of the groove root; after melting the upper bevel, it is pulled diagonally to the lower side of the groove root. Once the lower bevel is melted and a complete molten pool is formed, the electrode is moved back to extinguish the arc. This movement of the electrode is what constitutes the arc extinguishing motion, and this process is repeated until the entire weld is completed ； 4) “Upward push during overhead welding” means that after starting the arc in overhead welding, a rapid upward force is applied to the electrode in order to lower the arc and melt the root edge; this ensures that the groove is filled with molten iron, preventing collapse on the back side, while also avoiding the flow of molten iron on the front side and the formation of weld beads.