Spot welding is most commonly used for the joining of sheet metal.  However, this process can be used for joining a wide variety of metals.  

• Resistance welding equipment has many uses that many people often don't think about.
• Everyday items that some may not associate with resistance welding owe their very existence to this versatile process.
• To most manufacturers, spot welding is the most economical way to join two pieces of sheet metal.
• While joining sheet metal is the most common use for the process, resistance welding (RW) equipment actually can be used for a large variety of joining and heat-treating projects, some of which are not so well-known.
• Resistance Welding Annealing Annealing of production components often is required.
• Eighty-four individual spot welds are inside a four-slot toaster
• Joining Dissimilar Metals Using Percussion Welding
• The trick to this process is synchronization between the nail feed and the welding control.
• During destructive testing, the stamped part is gripped in a vise just below the pivot hole, and a hammer is applied to the side of the hardened ball.

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