What is EDM Machining (electrical discharge machining) and How Does It Work?

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What is EDM Machining (electrical discharge machining) and How Does It Work?

What Is EDM Machining

What Is EDM Machining

EDM is a machining process that uses electrical currents to cut metal. An edm machine contains three main components: an arbor, the electrode holder and the dielectric fluid.

The arbor is the drive shaft of the machine which rotates at high speeds in order to force metal into the cutting area. The dielectric fluid acts as a insulator between the electrodes and prevents them from short-circuiting together when in contact with each other. The electrodes are shaped like nails that are driven into the metal, this creates sparks which then create chips from the material being cut after being forced into it by high-speed rotation of an arbor.

It is used to create complex shapes and holes that are impossible to cut with conventional tools. EDM machines can be used to make parts for anything from circuit boards and laptop computers to cars and boats. The process has many advantages over conventional machining processes such as lathes and drills.

The advantages of EDM machining are:

  • – It has a high precision, accuracy and speed in comparison to other manufacturing processes
  • – It is not limited in its complexity or size because it can be used on any type of object, in any size and with a wide range of materials

EDM stands for Electrical Discharge Machining. EDM is a process of cutting where the cutter is either an electrode or a wire. The electrode/wire are electrically charged and are held at a high voltage usually in the range of 20 to 50 thousand volts. The material to be cut is then put into contact with this charged electrode or wire, thereby creating an electric arc that melts the material being cut.

Electrical Discharge Machining is a metal removal process that does not remove as much material as traditional machining, but provides more accurate and finer surface finish.

In EDM, metal is removed from a workpiece through the discharge of electrical current from an electrode to an oppositely charged electrode that has been inserted into the workpiece. The metal is then vaporized or melted away.

EDM has many different types of machines, and these machines can be separated into three different types: wire EDM, sinker EDM, and hole drilling EDM.

  • Wire EDM use a wire electrode to cut shapes out of the metal.
  • Sinker EDM use a sinking head to form shapes in the metal.
  • Hole drilling EDM are used when you are not able to get close enough to the material for traditional machining.

EDM machining process

For edm machining process, tool and workpiece must be electrically conductive. The machine is equipped with a special spindle and fixture to hold the workpiece securely in place while it undergoes milling.

The machining process begins with the use of a CNC-controlled end mill to cut a shallow groove in the surface of the workpiece, usually made from aluminum or steel. The groove is then filled with copper or brass by an electrochemical deposition (ECP) process.

  • 1) The first step is to prepare the part for edm machining. This may include clamping the part in a fixture, or it may involve cutting off excess material with a water jet or other tool.
  • 2) The second step of the process is to cut the material with an edm machine. The depth of cut can vary considerably depending on what is being machined, but there are often some features that are common in most molds. These features are often high on one side and lower on another side for easy removal from the mold after it is finished being machined.
  • 3) After this step, you must measure how deep each cut was made so that you know where to stop cutting at each point around.

EDM machining cost:

The cost of edm machining depends on various factors. These factors are the type of edm machine, the size of workpiece, material, tolerances, production volume and surface finish. The higher these factors are, the more costly edm machining will be.

High production volume is often a deciding factor in edm machining cost. This is because it requires less time to do multiple pieces with automation equipment rather than doing one piece at a time by hand for example.

In the past, it was difficult to get a price quote on edm machining. However, with the emergence of technology and affordable machines, it is now easier to get information on cost.

Edm machining cost is affected by many factors such as tooling costs, machine size, materials and cutters. The price also depends on the material that you are going to cut out of your metal sheet. For example, if you want to make a frame for an ornament out of steel sheet then the edm machine will cost more than if you want to make a jig for cutting tile into squares.

The average edm machining cost ranges from $11 per hour up to $25 per hour depending on the type of machine used, its condition, and other factors which are discussed below:

  • – Type of machine being used
  • – Size of material being machined
  • – Location (in case it is a custom order)
  • – Timing for machining each part

Advantage and disadvantage:

Advantages: Edm machining is advantageous because it can be used on castings, molds, or even large pieces of metal.

Disadvantages: Edm machining has disadvantages because it cannot be used on plastics.

EDM Machining Services at 3Q Machining for Your Precision Parts

EDM Machining Services at 3Q Machining for Your Precision Parts

We 3Q Machining offer a wide range of CNC machining services from process engineering to contract manufacturing. We have more than 10 years experience with machine tooling, integrated production systems, and machining expertise.

In addition to machine tooling, we offer a full range of advanced manufacturing services including contract manufacturing, product design, process engineering and inspection.

At CDM Machining Services we are committed to satisfying our customer’s needs by providing quality products that meet their specifications on time and within budget.

Author: Mose Li

Author: Mose Li

Director of Project Engineering at 3Q Machining

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