by Kat Griffin Kat Griffin

Tapping Electrodes: Applications & Types

copper impregnated tapping electrodesIn the context of the Electrical Discharge Machining (EDM) industry, tapping electrodes refer to a specific type of electrode used in EDM processes. They are used to remove material from a workpiece in order to shape it into a desired form.

In machining processes, tapping electrodes play a crucial role in creating precise and accurate threads in a variety of materials, including metals that are difficult to machine using conventional methods. This is particularly important in manufacturing industries where threaded components are commonly required, such as aerospace, automotive, and tooling.



Tapping electrodes used in EDM can be categorized based on the materials they are made of. Below are just some common types of tapping electrodes along with the materials typically used for their construction:


Graphite/Copper Graphite

Graphite tapping electrodes are widely used due to their excellent electrical conductivity and high temperature resistance. They are suitable for machining a wide range of materials, including hardened steels, aluminum, and other alloys. Graphite electrodes offer good wear resistance and can maintain their shape and dimensions during EDM operations.

Copper Tungsten

Copper tungsten is recommended for tapping tungsten carbide/carbide, titanium, and refractory metals, especially in smaller sizes where metals offer strength and maintain sharp edges. This material blends the high electrical conductivity of copper with the exceptional hardness and wear resistance of tungsten. These electrodes exhibit superior thermal conductivity, wear resistance, and compatibility with a diverse range of materials, making them ideal for precise material removal in EDM operations. 

The choice of electrode material depends on factors such as the specific machining requirements, the properties of the workpiece material, and the desired surface finish.


Factors Influencing Performance

Several factors influence tapping electrode performance in EDM, including material composition, electrical discharge parameters, workpiece material, EDM fluids, machining environment, machine setup and maintenance, and operator skill. The material from which the electrode is made affects its conductivity, hardness, and wear resistance, while its geometry impacts access to tight spaces and material removal efficiency. Proper selection of electrical discharge parameters and EDM fluids, along with stable machining conditions, is crucial for achieving optimal results. Additionally, maintaining equipment and ensuring operator proficiency are essential for maximizing tapping electrode performance and achieving high-quality machining outcomes.

Overall, considering and effectively managing these factors is essential for maximizing tapping electrode performance and achieving high-quality results in EDM and other machining operations.


Contact Us for a Quote Today

MWI provides tapping electrodes, including standard and orbital types, available in EC-15, EC-15C, and copper tungsten, which are customized to order upon request. We also offer these options in metric sizes. Check out our EDM Tapping Electrodes data sheet for more information. For tapping electrode inquiries, please reach out to us today at

by Kat Griffin Kat Griffin

Why Should I Use Copper Impregnated Graphite: EC-15C and HK-6C?

copper impregnated graphite

Copper impregnation provides increased resistance to erosion and corrosion, making Copper Impregnated Graphite suitable for harsh operating conditions and chemically aggressive environments. Copper Impregnated Graphite, specifically EC-15C and HK6-C grades, offer several advantages that make them a preferred choice in various applications like electrodes. 

top 3 benefits of using copper impregnated graphiteSome reasons you should consider using EC-15C and HK-6C grades include:

  1. Higher Electrical Conductivity:

    Copper impregnation significantly improves the electrical conductivity of the graphite material. This makes it ideal for applications where high electrical conductivity is essential, such as in electrical discharge machining (EDM), electrical contacts, and other electrical applications.

  2. Flexural Strength:

    Flexural strength is a crucial aspect to consider when evaluating electrodes. Unlike other materials, copper graphite is suitable for wire EDM to cut at higher speeds and provide finer finishes. EC-15C and HK-6C is an excellent choice for EDMing carbide and exotic alloys, as well as work pieces with limited flushing conditions. 

  3. Improved Thermal Conductivity:

    Copper impregnation also enhances the thermal conductivity of the graphite material. This property enables efficient heat dissipation, making it suitable for applications that require effective thermal management, such as heat sinks, thermal interfaces, and electronic cooling systems.

  4. Increased Mechanical Strength:

    Copper impregnation strengthens the graphite matrix, resulting in improved mechanical strength and stability. This makes Copper Impregnated Graphite more resistant to chipping when machining thin ribs and sharper detail, ensuring better durability and resistance to wear or deformation in demanding applications.

  5. Electrode Wear:

    Copper impregnation provides increased resistance to erosion, making copper graphite suitable for harsh operating conditions and chemically aggressive environments. Utilizing this metal is less prone to DC arcing in poor flush conditions. 

  6. Metal Removal Rates (MRR):

    Copper graphite used on common metal substrates have higher metal removal rates in roughing applications than standard graphite. Properties of copper graphite offer lower resistivity, higher flexural strength, high conductivity, and better finish with lower amperage settings which improves electrode wear.

  7. Versatile Applications:

    Copper Impregnated Graphite finds applications across various industries, including automotive, aerospace, electronics, power generation, and more. It can be used in EDM electrodes, current-carrying components, thermal management solutions, seals, gaskets, and other high-performance applications.

It is important to note that when selecting the appropriate electrode material for an EDM job, several factors come into play. Copper impregnated graphite has proven to be a suitable choice for EDM electrodes in various applications. However, the decision to opt for this material depends on specific application requirements and the desired outcomes. It is crucial to evaluate these variables carefully in order to make an informed choice regarding the use of copper impregnated graphite as the electrode material.