Custom EDM Drills

For Every Application, a Custom Electrode

Something as simple as a hole can perform a bewildering variety of functions, and to think of holes as having standard sizes makes little sense. For an EDM small hole drilling machinist, every job presents unique challenges requiring unique solutions. Often, this means a unique electrode, as an electrode’s performance is dictated by its dimensions and other characteristics, such as the material. Characteristics that may be adjusted are as follows:

• The outer diameter may be modified to a precision of +0 mm/-.005 mm (+0″/-.00019″).
• The length of electrodes can go from 50 mm (2”) to 800 mm (32”).
• The internal diameter may be decreased or increased, independent of the outer diameter.
• The wall thicknesses of internal channels or the outer walls may be adjusted.
• The material can be changed to leverage material advantages in specialized applications. Proportions of materials in alloys can be changed as well, such as with copper-tungsten.
• Electrode Spec Sheet

To those unfamiliar with the complex dynamics of electrode-workpiece interaction and the many factors involved, knowing what can be changed about an electrode says nothing about what ought to be changed. This is where we come in. Our expertise in EDM comes from more than 18 years of experience fielding and resolving the engineering challenges of pioneering companies in the most technologically demanding industries, such as aerospace, defense, and biomedical engineering. This experience has given us an intuitive feel for our customers’ needs, and for what can fulfill those needs.

Case Studies

Many companies have approached us desiring to increase their production efficiency. This is a problem with many solutions, depending on the context. Sometimes this can be resolved by lengthening an electrode. Not surprisingly, a longer electrode can burn through more parts, and has to be changed less frequently. Sometimes a material change is required. For one customer using copper electrodes, changing the alloy specification provided the desired increase in overall performance.

Companies have approached us needing better internal flushing characteristics, without changing the outer diameter of the tube. For this, the inner diameter may be increased, or a different inner-channel configuration used.

The channel configuration of an electrode can also make a difference in blind hole drilling. Whether an electrode is made with two or three channels, or even with wire inserts, depends on many factors. Though all will alleviate problems with leftover, unburned slugs or nipples, some pose different advantages or disadvantages depending on the exact application.

Where materials are not elementally pure, the exact mixture can result in an electrode with different characteristics. This applies to tungsten carbide and copper-tungsten. Copper-tungsten in particular exhibits great variation in burning characteristics depending on the ratio between copper and tungsten, and this should be considered in your application.

Why Use Custom Electrodes?

You might not have the time to think about all the factors that might improve electrode performance. Maybe you can simply adjust the settings of your EDM hole-popping machine. Maybe your production run is not large enough to justify the extra investment in time. In spite of these sensible objections, it often happens that customization is still the better choice.

If you’re hesitant to purchase custom electrodes because untangling the different electrode characteristics and how they might affect performance seems unnecessarily risky, leave it to us. Our experience gives us an idea of what you need to achieve your goals. For completely novel electrodes, we make small test batches, and assume the financial risk.

If you’re trying to drill holes with a slightly larger diameter than your current electrodes, you might be tempted to use more power. In exchange for convenience, this shortcut sacrifices precision, increasing the surface roughness and carbon build-up from oxygen, and aggravating the heat-affected-zone, or HAZ. This increases wear on all consumable parts, including the electrode, guide, and chuck, which results in significant overhead over time. Getting an electrode tailor-made for an application avoids these compromises.

If you’re worried about increased lead times where production runs aren’t long, our stocking system minimizes this. Using the proven just-in-time manufacturing method, we stock our supplies based on demand, and anticipation of demand.