Online Electrical Discharge Machining Service | CNC Lathe Live Tooling and Production Parts

Overview

Our EDM Service

What is Electrical Discharge Machining (EDM)

EDM is a special processing method that uses the electric erosion effect generated by the pulse discharge between the two electrodes immersed in the working fluid to remove conductive materials.

How Does EDM Work?

During EDM, the tool electrode and the workpiece are respectively connected to the two poles of the pulse power supply, and immersed in the working fluid, or the working fluid is filled into the discharge gap. The tool electrode is controlled to feed to the workpiece through the gap automatic control system. When the gap between the two electrodes reaches a certain distance, the pulse voltage applied to the two electrodes will break down the working fluid and generate spark discharge. A large amount of heat energy is concentrated instantaneously in the tiny channel of discharge, the temperature can be as high as 10,000 degrees Celsius, and the pressure also changes sharply, so that a small amount of metal material on the working surface immediately melts and gasifies, and splashes into the working fluid in an explosive manner In the process, it condenses rapidly to form solid metal particles, which are taken away by the working fluid.
At this time, a tiny pit trace is left on the surface of the workpiece, the discharge pauses for a short time, and the working fluid between the two electrodes returns to the insulating state. Immediately afterwards, the next pulse voltage breaks down at another point where the two electrodes are relatively close to each other, generating spark discharge, and repeating the above process. In this way, although the amount of metal removed by each pulse discharge is very small, because there are tens of thousands of pulse discharges per second, more metal can be removed, which has a certain productivity. Under the condition of maintaining a constant discharge gap between the tool electrode and the workpiece, while removing the metal of the workpiece, the tool electrode is continuously fed to the workpiece, and finally the shape corresponding to the shape of the tool electrode is processed. Therefore, as long as the shape of the tool electrode and the relative motion between the tool electrode and the workpiece are changed, various complex profiles can be processed.
Tool electrodes are usually made of electro-corrosion-resistant materials with good conductivity, high melting point and easy processing, such as copper, graphite, copper-tungsten alloy and molybdenum. During the machining process, the tool electrode also has loss, but it is less than the erosion amount of the workpiece metal, and even close to no loss. As the discharge medium, the working fluid also plays the role of cooling and chip removal during the machining process. Commonly used working fluids are media with low viscosity, high flash point and stable performance, such as kerosene, deionized water and emulsion. EDM mainly includes two process methods of electric discharge forming and electric discharge wire cutting.

Other Benefits of EDM

The cutting speed is fast, which can realize fast machining, especially for hard metal materials. High processing precision, EDM can provide fine and smooth surface quality. The cutting depth is controllable, and the cutting depth can be adjusted according to the characteristics of the workpiece. It has a wide range of applications and can be used to process various metal and non-metal materials.
In general, EDM is an efficient and precise cutting process suitable for machining various metals. But at the same time, safety measures need to be taken to prevent harm to the human body.

Features of EDM

Advantages

Wide range of applications

It can be processed regardless of the thickness and hardness of the material. As long as it is a conductive material, it can be processed from a thin plate to a cemented carbide, regardless of the thickness, size and hardness of the material.

Complicated shapes can be processed

In addition to straight cutting, it is also possible to cut into arcs and process complex shapes, such as a combination of straight lines and arcs. Taper processing is also possible by moving the upper and lower wires separately.

High precision

The accuracy of wire cutting is comparable to that of a grinder (0.005 mm unit).

Reduce material damage

Since wire cutting is a non-contact process, the load on the material is not too great and the thermal deformation is minimal.

Drawbacks

Bottom processing is not possible

Since wire cutting is a wire saw, it cannot be processed with the bottom. If you want to EDM the bottom, then a sinker EDM is the best choice.

Slow processing

It cuts while gradually melting the workpiece, so it works slower than cutting and is not suitable for mass production. Its speed is a few millimeters per minute, and it is barely visible to move with the naked eye.

Non-conductive materials cannot be handled

While conductive materials can be processed regardless of their hardness, non-conductive materials cannot.

Available materials for CNC machining

Here is a list of our standard CNC machining materials available through our online platform.

CNC Metals

Aluminum	Stainless steel	Mild, Alloy, Tool & Spring steel	Other metal
6061	304	Mild steel 1018	Brass C360
7075	316/316L	Mild steel 1045	Copper
5052	303	Mild steel A36	Titanium Gr5 (TC4)
2A12	430	Alloy steel 4140
	201	Alloy steel 4340
		Alloy steel 1215
		Tool steel D2
		Tool steel A2
		Tool steel D1
		Tool steel A3
		Tool steel S7
		Tool steel H13
		Spring steel

CNC Plastics

Plastic	Reinforced Plastic
ABS	PMMA (Acrylic)
ABS Flame Retardant	PEEK
ABS Transparent	Bakelite
Polycarbonate (PC)	FR4
Nylon 6
Nylon 12
Polypropylene (PP)
POM
PTFE (Teflon)
Polyethylene (PE)
Rubber

Custom Material

The materials available on the online system may not be exhaustive of all materials available on the market. If the materials you need are not listed on the order page, please select "custom" under the material menu, and our engineers will review and purchase.

Our standard surface finishes

Standard (As-Milled) (Ra 125μin)

The finish option with the quickest turnaround. Visible tool marks, potentially sharp edges and burrs would be removed by default.

Learn More

Bead blast + Anodized color

Anodizing creates a corrosion-resistant finish. Parts can be anodized in different colors—clear, black, red, and gold are most common—and is usually associated with aluminum.

Learn More

Anodized

It creates a corrosion-resistant finish. Parts can be anodized in different colors—clear, black, red, and gold are most common—and is usually associated with aluminum.

Learn More

Electrically conductive oxidation

It creates a corrosion-resistant finish, the film produced by conductive oxidation is only 0.01-0.15 micrometers,

Learn More

Black oxide

Black oxide is a conversion coating used to improve corrosion resistance and minimize light reflection.

Learn More

Brushed

Brushing is a surface treatment process in which abrasive belts are used to draw traces on the surface of a material, usually for aesthetic purposes.

Learn More

Bead Blast

The part surface is left with a smooth, matte appearance.

Learn More

Spray painting - Matt paint

Spray painting: Using spray guns with air pressure to disperse into uniform and fine droplets and apply the painting to the surface of the object.

Learn More

View more surface finishes

FAQ's

What is CNC machining?

CNC machining is a modern manufacturing technique that utilizes programmable software and computer-controlled equipment to create complex parts and products from a wide range of materials such as metal, plastics, and wood.

With CNC (Computer Numerical Control) technology, the manufacturing process is highly automated and precise. The process begins with a CAD (Computer-Aided Design) file, which is converted into a set of instructions in the form of G-code. This code is then sent to a CNC machine, which follows step-by-step instructions to produce the desired part or product.

CNC machining has revolutionized the manufacturing industry by increasing productivity, improving accuracy, reducing waste, and allowing for complex shapes and designs to be produced with high precision. It is used in a variety of industries, including aerospace, automotive, electronics, and medical devices.

What are the benefits of using CNC machines?

The benefits of using CNC machines are:

1. Enhanced precision: CNC machines can produce highly precise and accurate parts with tolerances as low as 0.0002 inches, which is not possible manually.

2. Increased speed: CNC machines are automated and can run 24/7, thereby offering faster production time for large volumes of parts.

3. Consistency: Unlike manual production, CNC machines produce parts that are identical in terms of size, shape, and quality consistently.

4. Reduced labor costs: CNC machines require less manual labor and supervision, which saves labor costs and improves overall efficiency.

5. Flexibility: CNC machines can be reprogrammed easily to create different parts without the need for complex tool changes.

6. Ability to work with a wide range of materials: CNC machines can work with a variety of materials, including metals, plastics, wood, and composites.

7. Improved safety: CNC machines can run automatically, which reduces the risk of injury for workers and provides a safer work environment.

8. Reduced waste: The precision offered by CNC machines reduces the material waste and scraps generated during the production process.

What types of materials can be used with CNC machines?

CNC machines can work with a wide range of materials including metals, plastics, wood, composites, ceramics and more. The types of materials that CNC machines can work with depend on the specific capabilities of the machine, the tooling options available, and the type of work being performed. Here are some examples of materials that can be used with CNC machines:

1. Metals: CNC machines can work with a variety of metals, including steel, aluminum, brass, titanium, copper, and more.

2. Plastics: CNC machines can work with various types of plastics such as polycarbonate, acrylic, nylon, ABS, PVC, and more.

3. Wood: CNC machines also perform operations on hardwood, softwood, plywood, and MDF board.

4. Composites: CNC machines can work with glass and carbon fiber composites, Kevlar, and other composite materials.

5. Ceramics: Machinable ceramics can also be used with CNC machines like porcelain, alumina, zirconia and other materials.

It's important to note that different CNC machines will have specific requirements for the materials that can be used. The feed rate, chip load, and spindle speed will vary depending on the material, so it's essential to understand the material properties and choose the appropriate tools and settings for each job.

What is the difference between CNC milling and CNC turning?

CNC turning and CNC milling are both processes used in CNC machining, but there are some significant differences between the two.

1. Operation: In CNC turning, a stationary cutting tool is used to remove material from a rotating workpiece, whereas in CNC milling, the cutting tools rotate and move across the stationary workpiece.

2. Geometry: CNC turning is more suitable for creating cylindrical shapes such as bolts, nuts, pipes, and shafts. CNC milling is better suited for more complex geometries such as pockets, slots, and complex shapes.

3. Tooling: Turning tools are generally simpler and more robust, while milling tools are more complex and can have more cutting edges.

4. Materials: CNC turning machines are mostly used for turning materials such as round bars, billets, and blocks, while CNC milling machines are used for a wide range of materials such as metals, plastics, wood, and composites.

5. Speed: In general, CNC turning is faster than CNC milling, as the tools are shorter and the process is simpler.

6. Cost: CNC turning is usually less expensive than CNC milling, as the tools are simpler and less expensive.

In summary, CNC turning is best suited for creating simple cylindrical shapes, while CNC milling is better suited for creating more complex geometries. Both processes have their advantages, and the choice between them will depend on the specific requirements of each job.

What is the maximum size of parts that can be machined with CNC machines?

The maximum size of parts that can be machined with CNC machines depends on the size and capacity of the machine being used. CNC machines come in various sizes, and they have different work envelopes that dictate the maximum size of parts they can handle.

Small CNC machines are ideal for small and intricate parts, while larger machines are used for bigger parts. Generally, the maximum size of parts that can be machined on a CNC machine ranges from a few centimeters to several meters.

For example, a small benchtop CNC milling machine may have a work envelope of around 300mm x 300mm x 200mm, while a larger vertical machining center may have a work envelope of 2000mm x 1000mm x 1000mm. In comparison, large gantry-style CNC machines used in the aerospace industry have a work envelope of over 30 meters in length.

It's essential to consider the size and weight of the parts being machined and the capabilities of the CNC machine when selecting a machine for a specific job.

CNC Machining Case Study