Metal Must Be Clean

• To TIG weld a metal, it must be clean. It is best to clean the metal before welding in any case, but TIG welding needs an unblemished area for the welding to hold properly. No rust, grime or dirt is allowed for proper TIG welding to occur. The weld will adhere to the rust or dirt and break off while welding. Any item left on the metal will cause porosity and pinholes due to the reaction with the welding rod.
  
  

Check Tungsten Length

• When placing the tungsten inside the TIG cup, ensure the tungsten is not sticking out too far or too deep inside the cup. Too long of a tungsten will create a longer arc and cause the rod to ball up. The arc needed to create a strong enough puddle will not be produced if the tungsten cannot reach the correct angle. The arc angle must be around 10 degrees. Therefore, the tungsten should sit about 3/8 inch outside of the TIG cup.
  
  

Check Aluminum Alloy

• Some aluminum is not strong enough for a TIG welding. A thinner alloy will not hold the weld and could break, causing accidents and injuries. If a TIG welding is the only way to connect two pieces of aluminum, the welding will have stress corrosion and break if too much weight is applied. A decorative welding on a flower box will hold but a weld on a weaker aluminum alloy used for a race car would not last.
  
  

Create A Vent Hole

• When TIG welding anything that will be entirely closed, place a vent hole in it. When welding, the air inside of a metal object will heat up and expand. The pressure that is built up while welding will blow out the end of the weld. The longer the welding time, the more the air inside is heated up. With a small vent hole drilled into the piece, the heat is released. The hole is easily welded without heating the air inside.