EDM drilling machines have evolved far beyond simply punching small start holes for wire EDM cutting. With today’s high demands and tight tolerances, surface preparation for better EDM drilling is more important than ever. That’s why machines such as the River series EDM hole drilling machines from Ocean Technologies combine 5-axis Tool Center Point (TCP) control with a built-in milling function to meet the challenges of complex aerospace component manufacturing.
3 Critical Features for Complex Aerospace EDM Drilling
1. Orbiting Head for Greater Flexibility
Three critical drilling machine features are necessary to fulfill these demands. First, an orbiting head is required, whether on aram-type or gantry-type design. The River 600, 700, 800, and 1000 model hole drillers all offer an orbiting head that moves side-to-side within a ±45° range. The orbiting head also allows for drilling holes larger than the electrode diameter by swinging the electrode outward slightly during the process, offering additional flexibility.
2. Tool Center Point (TCP) Control for Extreme Accuracy
While the head orbits, the River’s TCP feature automatically adjusts and compensates for electrode movement over curved and contoured parts, ensuring that the tip of the electrode (the “tool center point”) remains exactly on the programmed path, even as the head tilts and rotates in 5-axis motion. TCP is especially critical for drilling angled holes through complex surfaces without manual offsets, a necessity for aerospace components that demand the highest accuracy, such as turbine blades and engine nozzles, where cooling holes must be precisely oriented to aerodynamic surfaces. Having TCP significantly eases the programming burden when drilling thousands of holes at different angles across a single component.
3. Built-In 5-Axis Milling Function for Seamless Machining
Combining TCP with the River’s built-in 5-axis synchronized milling function enables milling directly on complex angled and curved surfaces. Rather than removing the part and transferring it to a CNC milling machine or grinder, the built-in milling feature allows the component to remain in place — avoiding errors commonly caused by re-handling and second operations — without requiring manual adjustment calculations for tilts or rotations. Aerospace parts including blades, vanes, fuel-system components, and 3D-formed parts often require milling operations such as flats, slots, and spot faces.
Why Milling Before Drilling Matters
Drilling into rough castings is typically unsuccessful without preparation, as an electrode can skate, bend, or wander off-point, leading to poor hole location accuracy, electrode breakage, and bad hole entry shapes. Milling a spot face or flat prior to drilling provides the perfect starting surface. Milling the flat at the correct angle ensures proper electrode alignment, reduced electrode deflection, and better control over the hole’s entry angle and quality.
Spot faces, when milled simultaneously using TCP, are much more accurate and critical for sealing, seating, or joining parts in assemblies. They are also important to ensure bolt heads, washers, and nuts sit flush with their mating surfaces, reducing friction and ensuring safety.
Reduced Costs and Improved Efficiency
The built-in 5-axis synchronized milling function reduces part handling and fixturing costs, eliminates the need for investment in specialized CNC milling equipment for secondary operations, and minimizes floorspace congestion.
A Complete Solution for Aerospace Manufacturing Challenges
When combined — the orbiting head, TCP feature, and built-in milling function on Ocean Technologies’ River series small hole EDM drilling machines dramatically improve hole quality, shorten production cycles, reduce part handling, lower costs, and enable precision machining on complex surfaces. These capabilities provide the critical advantages demanded by today’s aerospace industry.
Learn More About Our EDM Solutions
For more information about our EDM hole drilling, die sinking, or CNC wire EDM machines, contact Mark Cicchetti, EDM Technical Director at Absolute Machine Tools, at mcicchetti@absolutemachine.com or (616) 916-2775 (cell).
