Metal Drill Bits: Clean, Accurate Holes in Steel, Stainless Steel & Non-Ferrous Metals
Metal drill bits (twist drills) are the go-to choice when you need precise holes, controlled chip removal, and dependable tool life. Whether you’re drilling mild steel, stainless steel, aluminum, or other non-ferrous metals, choosing the right bit material and point geometry makes the difference between smooth cutting and excessive heat, chatter, or premature wear.
In this category you’ll find individual metal drill bits for targeted applications—so you can match diameter, length, point angle, and substrate (HSS, cobalt/HSSE, carbide) to your material and setup.
What Matters Most When Choosing Metal Drill Bits
Key features of a proper metal drill bit
- Spiral flutes that evacuate chips efficiently and help reduce heat build-up.
- Point geometry (most commonly 118° or 135°) to suit different metals and drilling conditions.
- Consistent grind for better concentricity (runout), cleaner holes, and easier starts.
118° vs 135°: which point angle should you use?
Point angle affects how the bit centers, how much feed pressure you need, and how well it performs in tougher materials. A practical guideline:
- 118°: a popular general-purpose angle for many everyday metal drilling tasks.
- 135° (often split point): tends to reduce “walking” and can work better in harder or tougher metals with less required feed pressure.
HSS, HSSE (cobalt) and carbide: choosing the right substrate
For metal drilling, the drill bit’s substrate largely determines heat resistance, wear resistance, and how forgiving it is in real-world use:
- HSS: tough and versatile—great for many standard metal applications and more forgiving in less rigid setups.
- HSS-G (ground HSS): improved precision and hole quality thanks to a more accurate grind.
- HSSE / cobalt (commonly 5–8% Co): higher hot hardness and heat resistance—especially useful for stainless steel and tougher alloys.
- Carbide: very high wear resistance and performance in rigid setups, but typically more brittle and less tolerant of side load.
Practical tips for better results in metal
- Use the right speed: harder metals and larger diameters generally require lower RPM.
- Use cutting fluid: lubrication/cooling improves finish and extends tool life—especially in steel and stainless.
- Maintain steady feed: consistent pressure supports proper cutting and prevents rubbing (heat).
- Pilot drill when needed: for larger diameters, a pilot hole can improve accuracy and reduce load.
FAQ: Metal Drill Bits
Which drill bits are best for metal?
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The best choice depends on the metal and how you’re drilling. As a quick guide:
- Aluminum & non-ferrous metals: quality HSS or HSS-G for clean cutting and chip flow.
- Mild steel: HSS-G is a strong all-round option for accuracy and durability.
- Stainless steel & tougher alloys: HSSE/cobalt for higher heat resistance and longer tool life.
Which drill bit is most suitable for metal?
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For general metalwork, a ground HSS twist drill (HSS-G) is usually the best balance of price, precision, and durability. If you frequently drill stainless steel or tough materials, step up to HSSE/cobalt. For cleaner starts in hard metals, a 135° split point can help reduce wandering.
How can you identify a metal drill bit?
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- Twist-drill shape with spiral flutes designed for metal chips.
- Common point angles around 118° or 135°.
- Markings such as HSS, HSS-G, HSSE/Co (on the packaging and sometimes on the shank).
- Clean cutting edges and a tip geometry aimed at stable cutting rather than aggressive tearing.
What’s better: HSS or HSSE?
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HSS is a reliable standard for many metals and is generally more forgiving. HSSE (cobalt) offers higher hot hardness and heat resistance, making it the better choice for stainless steel and tougher steels—especially for repeated drilling or higher temperatures.
Are carbide or cobalt drill bits better?
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Both can be “better,” depending on your setup and material:
- Cobalt/HSSE: a practical upgrade for hard and stainless steels; a strong balance of toughness and heat performance.
- Carbide: maximum wear resistance and speed potential in rigid, well-aligned setups, but more brittle and sensitive to side load.
In many workshop and handheld scenarios, cobalt/HSSE is the most user-friendly high-performance option. Choose carbide when you have a stable machine setup and need top wear resistance.