First and foremost, machine selection is a huge part of operational efficiency in EDM. Depending on the application, moldmakers can choose from wire, drilling, sinker or some combination of the three.
Wire EDM: Choose a machine with the latest cost-saving features. For example, some machines have an operational mode that minimizes wire consumption by slowing down the wire feed. The right wire EDM can also help manufacturers save on energy and consumables, with features that control and optimize dielectric fluid volume and pressure, pump and filter operation, and resin consumption.
Drilling EDM: Moldmakers should look for machines that combat hole tapering—otherwise known as bullet nosing. To avoid this common problem, machines must not only use high-quality electrodes, but also feature a power supply with a low unload voltage—ideally less than 35 volts. This maintains a high speed, but reduces wear and tear on electrodes. The right type of dielectric fluid can also combat bullet nosing. Try tap water with the appropriate additives instead of de-ionized water.
CNC sinker EDM: These are ideal for cavity and rib machining, and as with wire EDM, selecting the correct machine is the key to productivity. Features such as c-axis, lateral servo, high-speed jump and state-of-the-art power-supply technology can reduce electrode wear and improve productivity. CNC sinkers with high-speed spindles can also perform the same job as an EDM drilling machine, but at a much smaller hole diameter and with more precision.
When it comes to purchasing any type of EDM, remember to consider its control technology. Many machines now have sophisticated software that incorporates 3-D modeling, which can significantly improve ease-of-use and operator efficiency.
When it comes to operational efficiency in EDM, machine selection is critical. Based on the type of application, molders can choose different tools such as sinker, wire and drilling machines. When choosing a wire EDM, it is best to pay attention to the latest cost-saving features. For instance, some of the machines are known to have operational mode that assists in reducing wire consumption by reducing the rate of wire feed. Choosing the best wire EDM is also vital in saving energy and consumption as they have features that assist in controlling and optimizing the filtration and pump operation.
Another thing mold makers need to pay attention to when choosing the right EDM machine is the whole tapering capabilities. One way of avoiding the problem, an EDM machine must be designed to use high quality electrodes and have a power supply with a low unload voltage. This helps in maintaining a high speed and reducing wear and tear on electrodes. Using the right dielectric fluid is vital in combating bullet nosing. Mold makers can also add the right additives to tap water instead of using ionized water.
Another thing con consider when searching for EDM machines is the ease of maintenance. Keeping your machine in good shape is vital. This means that when it endures damage, you need to find ways of fixing it. The ease of maintenance will depend on the type of locker you choose. When searching for the right EDM Machining, it is best to know the types of EDM available in the market. It is worth noting that there are three type of EDM operations; wire EDM, sinker EDM and small-hole EDM. Sinker EDM, for instance uses an electrode that is fabricated into a unique shape. The reverse of the shape is then imprinted. A sinker EDM uses a servo contour mechanism to monitor and maintain continuous sparking during the process. The best part of sinker EDM is that they are extremely accurate. They are most effective when parts need tight tolerances. They are also known to be versatile as they use parts of different sizes.
When looking for an EDM machine, you will find a wire EDM Machining. Like the name suggests, it uses a wire as the electrode. The wire used is spun between two reels during machining. The whole process is computer controlled, thereby improving efficiency. A wire EDM is best used for cutting delicate shapes effectively and efficiently. They are an idea for making contours and sharp corners.
Now that you understand the steps to follow when searching for the right EDM machine and the types available in the market, it is best to know the steps to follow when searching for the right EDM machine manufacturer. First, you may want to check the quality of the EDM machines of the manufacturers. When you choose the best quality, they will serve you for many years without having to replace them. Lower quality will only last for a few years. The difference in the quality of machines is in the quality of the materials used in making them.
EDM or Electrical Discharge Machining is a manufacturing process that is based on the controlled erosion of conductive materials using an electrode. It was first achieved in the 40s, but has developed into one of the most precise and high-quality metal removal processes available. EDM machines are generally used to achieve very complex shapes in extremely hard metals such as tungsten carbide, titanium, and hardened tool steel alloys.
How does EDM work?
There are two types of EDM machines: Die Sinker and Wire EDM. The operation of both is based on the same principle.
An electrical spark is created between the workpiece and a charged electrode using dielectric fluid as the media to control the flow of current. The CNC-controlled machine brings the two electrodes close enough to ionize the gap and superheat the surfaces of the workpiece and electrode.
Once the necessary temperature is achieved, discharge occurs and the material is vaporized. Once the material removed the generator will shut off for a short period of time allowing the vaporized particles to be flushed away in the dielectric fluid. This process repeats itself over and over again at frequencies of approximately 100,000 times per second during rough machining cycles.
In the case of Wire EDM, the role of the cutting electrode is fulfilled by a precisely manufactured brass wire ranging in diameter from 0.0005” to 0.013”. The wire is guided through the workpiece using precision diamond dies at both top and bottom of the workpiece. Sinker EDM typically uses a custom machined electrode made from various materials such as Graphite (carbon), Copper or more exotic materials such as Copper Tungsten.
Why is an EDM ideal for die/mold applications?
The manufacturing of highly tailored dies and molds call for extreme accuracy. As they feature demanding design points such as sharp internal corners, narrow slots, deep ribs and other intricate shapes. There is no other tool that can achieve the high-precision machining required for the man