Electrical Discharge Machining or EDM is a non traditional method of removing metal by a series of rapidly reoccurring electric pulses which are discharged between an electrode and the work piece.

EDM is used to machine features that would be difficult or impossible with other techniques. Hardened steel and exotic alloys pose little or no additional challenge over softer work pieces.

Advantages

• Intricate & complex details are possible
• Internal corners down to R .001" [.025mm]
• Small features down to .004" [.10mm]
• Extremely hard work pieces can be cut
• Very high accuracy attainable
• Precise control of surface finish
• No cutting forces
• Virtually no geometric limitations

Disadvantages

• Non conductive work piece’s cannot be cut
  
• Slower material removal rate than milling
  
• An electrode is required [Sinker EDM]

Examples of use