ONA Electroerosion TF300

$60,000 - $100,000 Updated 2026-03-17

Key Specifications

X / Y Travel

300 mm × 200 mm

Z-Axis Stroke

300 mm

Electrode Diameter Range

0.3 – 3.0 mm

Electrode Type

Rotating tubular (brass or copper)

Max Drilling Depth

300 mm

Drilling Speed (Steel, 1 mm electrode)

Up to 30 mm/min

Overview

The ONA Electroerosion TF300 is a dedicated EDM hole drilling machine, also known as a fast hole drill EDM or EDM drill, designed to produce precision start holes in hardened steel, carbide, and other difficult-to-machine materials. These start holes are required before wire EDM can thread through a workpiece, making the TF300 an essential companion machine in wire EDM departments that process through-hardened tooling and exotic alloys where conventional drilling is impractical.

The TF300 uses rotating tubular electrodes — typically brass or copper tubes ranging from 0.3 mm to 3.0 mm in diameter — through which dielectric fluid is pumped under pressure to flush debris from the hole as it is drilled by electrical discharge. This process enables hole drilling in materials of any hardness at rates substantially faster than EDM sinking with solid electrodes, and produces holes with excellent cylindricity even in steels above 60 HRC.

ONA's design for the TF300 emphasizes automatic depth control, electrode compensation for wear, and programmable multi-hole sequences on a single workpiece fixture. The machine's Z-axis servo provides precise depth control with automatic retract-on-breakthrough detection, which stops drilling as soon as the electrode exits the back face of the workpiece to prevent over-drilling or damage. Multi-hole programs can be executed using X/Y axis positioning, turning the TF300 into a productive hole pattern machine for large die plates.

The TF300 is equipped with a high-pressure dielectric pump delivering up to 8 MPa through the electrode, which is critical for achieving clean holes in deep drilling applications. The control includes pre-set depth programming, electrode diameter compensation tables, and a wear calculation display that alerts the operator when electrode replacement is needed. The compact footprint and straightforward setup make the TF300 a practical addition to any EDM or tool and die department.

Full Specifications

Parameter	Value
X / Y Travel	300 mm × 200 mm
Z-Axis Stroke	300 mm
Electrode Diameter Range	0.3 – 3.0 mm
Electrode Type	Rotating tubular (brass or copper)
Max Drilling Depth	300 mm
Drilling Speed (Steel, 1 Mm Electrode)	Up to 30 mm/min
Dielectric Pressure	Up to 8 MPa
Max Workpiece Weight	200 kg
Table Size (L × W)	400 mm × 300 mm
Spindle Speed	Up to 1,000 RPM
Breakthrough Detection	Automatic servo retract
Control	ONA-CNC with depth programming

Strengths & Limitations

Strengths

Drills precision start holes in hardened steel and carbide of any hardness where conventional drilling fails
High-pressure dielectric flushing (up to 8 MPa) enables clean holes at full depth without EDM recast layer issues
Automatic breakthrough detection prevents over-drilling and workpiece damage
X/Y axis positioning supports multi-hole programs on a single setup for die plates
Compact footprint and straightforward operation make it accessible for any EDM department

Limitations

Limited to hole-drilling operations — not a general-purpose sinker or wire EDM
Tubular electrode consumption adds ongoing consumable cost, particularly for small-diameter holes
Hole quality and roundness in thin sections can be affected by electrode runout if not managed

Best For

Producing wire EDM start holes in through-hardened tool steel plates (>55 HRC) before wire threading Drilling coolant holes in carbide tooling and hardened steel die components Creating injection gate, vent, and ejector pin holes in hardened mold blocks Multi-hole patterns in large die plates where conventional drilling is prohibited by material hardness

Frequently Asked Questions

01 Why is an EDM hole drill like the TF300 needed before wire EDM?

Wire EDM requires a start hole to thread the wire through the workpiece before cutting can begin. On hardened steel and carbide, conventional drills cannot penetrate the material, so an EDM hole drill burns a small hole (typically 0.5–1.5 mm) using a rotating tubular electrode and electrical discharge.

02 What electrode diameters does the TF300 support?

The TF300 accepts tubular electrodes from 0.3 mm to 3.0 mm in diameter. For wire EDM start holes, 0.5 mm and 1.0 mm diameter electrodes are most commonly used.

03 How fast does the TF300 drill in hardened tool steel?

With a 1 mm diameter brass tube electrode and full dielectric flushing, the TF300 achieves drilling speeds up to 30 mm/min in hardened P20 or H13 tool steel — far faster than EDM sinking with a solid electrode.

04 Does the TF300 have automatic breakthrough detection?

Yes. The Z-axis servo monitors discharge conditions and automatically retracts the electrode when breakthrough is detected, preventing over-drilling and damage to the fixture or back surface of the workpiece.

05 Can the TF300 drill holes in carbide?

Yes. Tungsten carbide, which cannot be conventionally drilled, is routinely processed on the TF300 using copper-tungsten electrodes at reduced current settings, enabling clean start holes in carbide die inserts and wear plates.