Iwaki, Japan – August, 2026 – Tungaloy Corporation (President: Satoshi Kinoshita, Head Office: Iwaki City, Fukushima Prefecture) announces the expansion of its DrillMeister series with the new radius cutting edge drill head DMR. Designed for cast iron machining, this replaceable head improves chip control and stability, reducing setup time while enhancing drilling efficiency.
Challenges and Trends
Drilling cast iron components is essential across a wide range of industries, including automotive brake and engine components, as well as frames and housings for industrial and construction machinery. Especially under demands for high machining efficiency, defects unique to cast iron, such as blowholes, often cause edge chipping and reduced tool life. Additionally, during high-feed drilling, burrs and edge break tend to occur at the hole exit area, creating factors that hinder stable machining quality and productivity improvements. To overcome these challenges, the development of drills with high chipping resistance and the capability to achieve stable, high-efficiency machining is required.
Product Overview
Tungaloy’s DrillMeister is a high-productivity drill series featuring replaceable heads that reduce setup time and deliver stable machining with a fresh cutting edge every time. They offer a wide range of body lengths to accommodate various diameters and drilling depths, along with a diverse lineup of heads to suit different applications. Featuring internal coolant and a helical margin design, DrillMeister delivers excellent chip evacuation, extended tool life, and high-precision drilling across a broad range of materials, from steel and non-ferrous materials to hardened steel.
The newly developed DMR head is a high-performance drill head specifically designed to address machining challenges in cast iron applications, featuring a dedicated radius cutting edge geometry.
Benefits and Features
Feature 1: Stress Dispersion at the Cutting Edges with a Dedicated Large Radius Cutting Edge
– A large radius cutting edge at the corner effectively reduces cutting edge stress during machining
– Significantly reduces stress concentration, minimizing chipping and damage while enhancing tool life
– Ensures stable drilling performance even under high feed conditions, providing reliable long tool life
Feature 2: Radius Cutting Edge Design to Improve Hole Quality at Breakthrough
– The cutting edge geometry reduces workpiece load during breakthrough, suppressing edge chipping and burr formation
– Reduces post-processing requirements in finishing operations, improving overall machining efficiency
– Achieves higher quality drilling, contributing to increased overall productivity in the process
Feature 3: Optimized Gash Geometry and High Wear-Resistant PVD Coating
– Optimally designed gash geometry promotes smooth chip formation and evacuation
– Prevents chip clogging and enhances stability during continuous machining
– Incorporates the latest PVD coating material “AH9130,” dramatically improving wear resistance and supporting extended tool life
Cutting Performance
■ Radius cutting edge dramatically reduces burrs and breakage
| Tool | ø14 mm, L/D = 3 |
| Drill head | DMR140 |
| Grade | AH9130 |
| Workpiece material | GGG60 Ductile cast iron |
| Cutting speed | Vc = 120 m/min |
| Feed per revolution | f = 0.45 mm/rev |
| Coolant | Internal |
| Machine | Machining center, BT40 |
■ Reinforced corner edge design delivers stable, long tool life even in high feed machining
| Tool | ø14 mm, L/D = 3 |
| Drill head | DMR140 |
| Grade | AH9130 |
| Workpiece material | GGG60 Ductile cast iron |
| Cutting speed | Vc = 120 m/min |
| Feed per revolution | f = 0.45 mm/rev |
| Hole depth | H = 20 mm (Through) |
| Coolant | Internal |
| Machine | Machining center, BT40 |
Success Stories
IMPROVED TOOL LIFE
Tool life was extended by up to 2.7 times by using the DMR head compared with a competitor’s exchangeable-head drill.
| Industry | Automotive |
| Component | Flywheel |
| Material ISO code |  Cast iron |
| Work material | FC250 / GG25 |
| Machine(Spindle type) | Vertical Machining Center |
| Tool family | Holemaking |
| Tool category | Drilling |
| Product name | DrillMeister |
| TSR No. | 5656D |
IMPROVED TOOL LIFE
Tool life was extended by up to 1.4 times by using the DMR head compared with an existing replaceable-head drill.
| Industry | Automotive |
| Component | Housing |
| Material ISO code | Cast iron |
| Work material | FCD600 / GGG60 |
| Machine(Spindle type) | Vertical Machining Center |
| Tool family | Holemaking |
| Tool category | Drilling |
| Product name | DrillMeister |
| TSR No. | 5657D |
