EDM HOLE
DRILLING
micro-diameter holes
Tolerances to ±0.0001″
in hardened steels
and alloys
EDM hole drilling, also known as micro hole popping or micro EDM drilling, is a highly precise method for creating small-diameter holes in conductive materials. At Twin City EDM & MFG, we use this technique to deliver tight-tolerance holes ranging from 0.004″ to 0.250″ in everything from stainless steel and titanium to exotic metals like Inconel and molybdenum. Our advanced 5-axis CNC EDM machines deliver unmatched precision for critical components across the aerospace, medical, defense, and other high-performance industries.
What Is Micro Hole Popping?
Micro hole popping is a specialized form of electrical discharge machining (EDM) that uses high-frequency electrical sparks to erode material and form tiny holes. This non-contact process is ideal for parts that are difficult or impossible to drill using traditional methods. It works particularly well with hardened or heat-treated metals.
Because micro EDM doesn’t exert mechanical force, it avoids stress or distortion in the workpiece. This makes it perfect for delicate parts with thin walls, complex geometry, or temperature-sensitive features.
Benefits of EDM Hole Drilling vs. Traditional Drilling
Compared to mechanical drilling, EDM hole drilling offers several key advantages:
- Works on Hardened Materials – Easily drills tool steels, carbide, titanium, and superalloys.
- No Tool Pressure – Prevents deformation in fragile or thin-walled parts.
- High Accuracy – Achieves hole tolerances down to ±0.0002″ with repeatability of ±0.0005″.
- Micro Diameters – Produces holes as small as 0.004″ with excellent edge quality.
- Complex Geometry – Allows angled holes, curved entry points, and custom hole patterns.
- Burns Through Tubing & Wire – Ideal for hypodermic needles, surgical tubing, and small nozzles.
This process is also highly automated, making it efficient for both prototyping and high-volume production.
How Micro EDM Drilling Works
Here’s a simplified breakdown of our micro hole drilling process:
- Setup and Fixturing: The workpiece is mounted in the EDM machine with precision alignment, based on your CAD model.
- Electrode Selection: Copper or brass electrodes are chosen based on material, hole diameter, and desired finish.
- Program and Burn: Our CNC system drives the electrode toward the material. A pulsed electrical current generates sparks that erode the workpiece—creating the desired hole shape without physical contact.
- Bath and Flushing: Fluid bath and flushing systems cool the part and remove debris, ensuring clean and consistent holes.
- Inspection and Testing: All parts are verified using high-resolution inspection systems, including Hexagon CMMs and OGP vision systems.
Past Projects
Twin City EDM’s EDM hole drilling process supports applications in:
- Hypodermic needle manufacturing
- Surgical and orthopedic tubing
- Aerospace fuel nozzles
- Defense components with fluid ports
- Filters requiring micro-perforation
- Aircraft spray and combustion systems
We regularly work with engineers to develop micro hole patterns and multi-hole arrays tailored to the performance needs of each project.
You Can Trust Our Experience and Quality Control Processes
We bring over 60 years of machining excellence to every project and specialize in hard-to-source micro-machining operations, such as EDM hole drilling. When your application demands extreme precision, quick turnaround, and strict adherence to medical, aerospace, or military standards, Twin City EDM delivers.
- ISO 9001:2016 Certified
- ISO 13485 Compliant for Medical Devices
- MIL and ASTM Standards Met
From single prototypes to full production runs, our team ensures your micro hole requirements are met with precision and consistency.
Request a Custom Quote
Need precision micro holes for your next project?
Our team is standing by to help you with any size project, from prototype to extensive runs.
Contact Twin City EDM for a custom quote on using EDM hole drilling for your next project.