In the world of metalworking and CNC machining, the humble twist drill is often taken for granted—until it fails mid-operation, ruining a workpiece and costing valuable production time. For professionals seeking reliability, versatility, and consistent performance, DIN338 drills represent the gold standard in jobber-length drilling tools -1.
The DIN338 standard governs the dimensions of jobber-length twist drills, specifying overall lengths, flute lengths, and shank diameters that have become the universal benchmark in the industry -2. Whether you are machining tool steel, stainless steel, cast iron, or aluminum alloys, understanding the nuances of DIN338 drills can significantly impact your shop’s productivity and bottom line.
At Grewin Tools, our GREWINTOOLS DIN338 DRILLS are engineered to excel across seven critical material categories:
- Tool Steel
- Brass
- High-Elastic Steel
- Aluminum Alloy
- Cast Iron
- Alloy Steel
- Stainless Steel
This comprehensive guide explores everything you need to know about selecting, applying, and maximizing the performance of DIN338 drills in your machining operations.
Understanding the DIN338 Standard: More Than Just Dimensions
What Defines a DIN338 Drill?
The DIN338 standard specifically defines jobber-length twist drills—the most commonly used drill type for general-purpose applications -2. Key characteristics include:
- Length-to-diameter ratio: Typically 5×D (five times the diameter), providing the optimal balance between reach and rigidity
- Tolerance class: Usually h8 for the nominal diameter, ensuring precision and interchangeability -1
- Shank design: Plain cylindrical shank, often with three drive flats on larger diameters for secure gripping in three-jaw chucks -1
The Anatomy of a DIN338 Twist Drill
A quality DIN338 drill comprises several critical elements:
| Component | Function | GREWINTOOLS Advantage |
|---|---|---|
| Point Angle | Determines cutting action and material penetration | 118° standard for universal application -3 |
| Flute Design | Facilitates chip evacuation | Optimized geometry for multi-material performance |
| Core Thickness | Provides torsional strength | Reinforced core for enhanced durability -1 |
| Shank | Transmits power from machine to tool | Precision-ground for concentricity |
Material-Specific Applications for DIN338 Drills
One of the greatest strengths of GREWINTOOLS DIN338 DRILLS is their versatility across diverse materials. Understanding how your DIN338 drill interacts with each workpiece material is essential for achieving optimal results.
Machining Steel Alloys with DIN338 Drills
Tool Steel and Alloy Steel
Tool steels and alloy steels present unique challenges due to their hardness and abrasiveness. When using DIN338 drills on these materials:
- Recommended cutting speed: 18-22 m/min for heat-treated steels -3
- Feed rate: 0.04-0.15 mm/rev depending on diameter -3
- Key consideration: Ensure rigid setup to prevent work hardening
Stainless Steel Applications
Stainless steel machining demands DIN338 drills with excellent edge retention and heat resistance:
- Material group: Austenitic and martensitic stainless steels -3
- Speed parameters: 6-14 m/min for optimal tool life -9
- Coolant requirement: Essential for preventing work hardening and achieving surface finish
High-Elastic Steel (Spring Steel)
High-elastic steels require DIN338 drills with:
- Sharp cutting edges to minimize deformation
- Consistent feed rates to avoid work hardening
- Adequate chip clearance due to stringy chips
Non-Ferrous Materials and DIN338 Drills
Aluminum Alloys
Aluminum machining with DIN338 drills offers excellent productivity:
- Speed range: 45-90 m/min for long-cutting aluminum -3
- Chip control: Polished flutes enhance chip evacuation
- Surface finish: 118° point angle provides clean entry and exit
Brass and Copper Alloys
For brass applications, DIN338 drills deliver superior results:
- Cutting speeds: 35-60 m/min for brass alloys -9
- Feed rates: 0.06-0.2 mm/rev for optimal chip formation -3
- Unique advantage: 118° point prevents “pulling” or grabbing common in brass
Cast Iron and DIN338 Drill Performance
Cast iron machining requires DIN338 drills with:
- Abrasion resistance due to graphite content
- Adequate chip breaking capability
- Speed parameters: 20-30 m/min for gray cast iron -3
Selecting the Right DIN338 Drill for Your Application
Coating Options for DIN338 Drills
The performance of your DIN338 drill can be dramatically enhanced by appropriate coatings:
| Coating Type | Benefits | Best Applications |
|---|---|---|
| Bright/Uncoated | Economical, sharp edges | General purpose, aluminum, brass -1 |
| TiN (Titanium Nitride) | Increased hardness, reduced friction | Steel alloys, stainless steel -3 |
| Steam Tempered | Improved lubricant adhesion | Ferrous metals, cast iron -9 |
| Multi-layer (Magma) | Extended tool life, higher speeds | Stainless steel, exotic alloys -7 |
Point Geometry Considerations
While 118° is standard for DIN338 drills, some applications benefit from variations:
- 118° Standard: Universal application across most materials -1
- 135° Split Point: Self-centering, reduces thrust requirements, excellent for stainless -2
- Stepped Tip: Ideal for thin materials and curved surfaces -1
Tolerance and Quality Grades
DIN338 drills typically feature:
- Diameter tolerance: h8 (suitable for general machining) -1
- Concentricity: Precision-ground flutes ensure high concentricity -1
- Edge preparation: Consistent cutting edge geometry for predictable performance
Optimizing Cutting Parameters for DIN338 Drills
Speed and Feed Calculations
Proper parameters are essential for maximizing DIN338 drill performance:
Recommended Cutting Speeds by Material
| Material Group | Cutting Speed (m/min) | Feed Rate (mm/rev for 5mm dia) |
|---|---|---|
| Tool Steel (<1300 N/mm²) | 6-10 | 0.04-0.10 -3 |
| Stainless Steel (Austenitic) | 8-15 | 0.04-0.10 -3 |
| Cast Iron | 20-30 | 0.06-0.20 -3 |
| Aluminum Alloy | 45-90 | 0.06-0.20 -3 |
| Brass | 35-60 | 0.06-0.20 -9 |
The 5×D Advantage
DIN338 drills are designed for drilling depths up to 5× diameter without pecking in most materials -4. This capability offers:
- Reduced cycle times
- Improved hole quality
- Extended tool life through consistent chip load
Coolant and Lubrication Strategies
Proper lubrication extends DIN338 drill life significantly:
- Steel alloys: Soluble oil or cutting oil recommended
- Stainless steel: High-performance cutting oil essential -10
- Aluminum: Light oil or mist cooling prevents built-up edge
- Cast iron: Can be run dry or with light air blast
Common Challenges and Solutions with DIN338 Drills
Chip Evacuation Issues
When DIN338 drills experience poor chip evacuation:
Symptoms: Packed flutes, increased torque, poor surface finish
Solutions:
- Increase coolant flow and pressure
- Implement pecking cycles for deeper holes
- Consider DIN338 drills with optimized flute geometry
Work Hardening in Stainless Steel
Stainless steel work hardening can destroy DIN338 drills quickly:
Prevention:
- Maintain consistent feed rate (never dwell)
- Use sharp DIN338 drills with proper edge preparation
- Ensure adequate coolant delivery to cutting zone
Achieving Hole Quality
For applications requiring superior hole finish with DIN338 drills:
- Verify machine spindle runout (<0.02mm recommended)
- Use rigid tool holding (hydraulic or shrink-fit chucks)
- Consider DIN338 drills with enhanced tolerance control -1
The Grewin Tools Advantage: GREWINTOOLS DIN338 DRILLS
Engineered for Versatility
Our GREWINTOOLS DIN338 DRILLS are manufactured to exceed industry standards, offering:
- Precision-ground flutes for consistent performance
- Optimized geometry across the full diameter range
- Rigorous quality control ensuring h8 tolerance compliance
- Multi-material capability from tool steel to aluminum
Quality You Can Trust
Every GREWINTOOLS DIN338 DRILL undergoes:
- Metallurgical analysis of raw materials
- Geometric verification against DIN338 specifications
- Performance testing across application materials
Comprehensive Size Range
We stock DIN338 drills from 1.0mm to 13.0mm, with both:
Best Practices for Extending DIN338 Drill Life
Proper Tool Handling
- Store DIN338 drills in organized cases to prevent edge damage
- Keep drills separated by size to avoid contact
- Maintain clean, dry storage conditions
Machine Setup Considerations
- Verify spindle concentricity regularly
- Use appropriate collets or chucks for maximum grip
- Ensure workpiece is securely fixtured
Process Monitoring
Watch for these indicators that your DIN338 drill needs replacement:
- Increased power consumption
- Deteriorating surface finish
- Unusual cutting sounds
- Burning smell or discolored chips
Frequently Asked Questions About DIN338 Drills
What is the difference between DIN338 and DIN340?
DIN338 drills are jobber length (standard length), while DIN340 specifies longer series drills for deeper applications. Choose DIN338 drills for general-purpose drilling up to 5× diameter -10.
Can DIN338 drills be used in portable drills?
Absolutely. DIN338 drills are designed for use in:
- Drill presses
- CNC machines
- Handheld electric drills
- Cordless drills -10
How do I select the right DIN338 drill for stainless steel?
For stainless steel, look for:
- DIN338 drills with 135° split point for self-centering -5
- HSS-Co (cobalt) or coated options -7
- Adequate coolant delivery capability
What feed and speed should I start with?
For unknown materials with DIN338 drills, begin conservatively:
- Start at 50% of recommended speed
- Observe chip formation and adjust upward
- Monitor tool wear and surface finish
conclusion: Maximizing Productivity with DIN338 Drills
The DIN338 drill remains the most versatile and widely used tool in metalworking for good reason. Its standardized dimensions, proven geometry, and adaptability across materials make it indispensable for job shops, production facilities, and maintenance operations alike.
With GREWINTOOLS DIN338 DRILLS, you gain:
- Versatility to handle seven material categories
- Reliability backed by strict quality control
- Availability in the sizes you need
- Support from experienced application engineers
Whether you’re machining tool steel for mold making, stainless steel for medical devices, or aluminum alloys for aerospace components, the right DIN338 drill makes all the difference.
Ready to Optimize Your Drilling Operations?
Contact Lydia Choo today for:
- Technical application support for your specific materials
- Competitive pricing on GREWINTOOLS DIN338 DRILLS
- Sample testing programs for qualified accounts
- Custom packaging and inventory solutions
📞 WhatsApp: 0086-18673327292
📧 Email: info@gwcarbide.com
🌐 Website: www.grewintools.com
Experience the Grewin Tools difference—precision engineered for performance.
