Tungsten Inert Welding (a.k.a. TIG welding or Gas Tungsten Arc Welding) is a form of arc welding used to produce high purity welds. For this reason, it is commonly used in the nuclear, aviation, food and beverage, and pharmaceutical industries. While MIG welding uses a metal coil that is fed continuously through the gun, TIG welding causes the base metal to be melted as the filler metal is handfed into the molten pool. This type of welding can be used on stainless steel, carbon steel, aluminum, and other non-ferrous metals.
While learning the fundamentals of TIG welding, beginners may struggle with proper technique. To help you on your way to achieving TIG welding certification, here are a few tips to keep in mind while you weld.
TIG Welding Techniques
- The angle of the torch should be 15 to 20 degrees away from the direction of travel. This increases visibility of the area and allows easier access for the filler material.
- The filler metal should be brought in at as low an angle as possible to help avoid touching the tungsten electrode and contaminating it.
- The torch melts the base material, and the molten puddle melts the filler rod. Resist the urge to melt the filler material directly.
- For preparing the tungsten, using a diamond grinding wheel will give you the best results for a sharp point. Tungsten should be held in line with the direction that the wheel is turning rather than perpendicularly. This will ensure the grind marks run the length of the tungsten, which assists the flow of the electric current as it travels down the electrode. Turn the tungsten as you hold it against the wheel, as if you are sharpening a pencil. For welding aluminum, you should then grind a flat spot at the very tip by holding the point flat against the grinding wheel.
- For welding stainless steel, be cautious of applying too much heat. The coloring of the weld should range from a flaxen to a salmon color. If the color is darker gray and looks dirty and heavily oxidized, too much heat is being applied. If too much heat is applied, the metal could warp. To correct this problem in the future, reduce the amperage and increase travel speed. You may also try reducing the diameter of the filler material, as that will take less energy to melt.