Drilling through stainless steel isn’t a job for just any tool. It’s a tough, heat-resistant material that punishes cheap bits and poor technique. If you’ve ever burned, dulled, or snapped a drill bit on stainless, you’re not alone. The good news? It’s completely avoidable—with the right bit, the right approach, and the right setup.
In this guide, we’ll walk you through how to drill stainless steel safely and efficiently without damaging your tool, wasting material, or risking downtime.
Stainless steel, particularly austenitic grades like 304 and 316, presents unique challenges:
High tensile strength (500–750 MPa)
Work hardening under friction
Low thermal conductivity (14–16 W/m·K), which traps heat at the cutting edge
According to Sandvik Coromant, these properties mean that excessive heat and low cutting pressure are the two biggest causes of bit failure.
Avoid standard HSS. You’ll want:
HSS-Co (M35 or M42): Heat-resistant cobalt alloyed HSS, ideal for moderate-speed drilling
Solid Carbide: Ultra-hard, wear-resistant, best for CNC or high-volume operations
Recommended Tool: [M35 Cobalt Drill Bit – DIN 338]
For stainless steel drilling with better red hardness and longevity.
For CNC/Production: [TiAlN-Coated Solid Carbide Drill – DIN 6537K]
With through-coolant options for improved chip evacuation and heat control.
135° Split Point: Prevents walking and reduces thrust force
Parabolic Flute or Web-Thinned Design: Enhances chip evacuation
TiAlN or AlTiN Coating: Protects against heat and oxidation
These features combine to reduce friction and resist wear.
Pro Tip: Avoid TiN-only coatings—they are not heat-resistant enough for stainless.
For M35 drills in 304 stainless, use:
Cutting speed: ~20 m/min (65 SFM)
Feed rate: 0.08–0.2 mm/rev (depending on diameter and machine)
Always drill slowly and steadily. Rushing only increases heat and shortens tool life.
Never drill stainless dry.
For handheld or drill press:
Use cutting oil (sulfur-based or synthetic)
For CNC or semi-auto:
Use through-coolant drills or flood coolant
Coolant prevents heat buildup, improves chip flushing, and protects the bit’s cutting edge.
Recommended Product: [Through-Coolant Solid Carbide Drill – DIN 6537]
Especially effective for deep-hole or production-grade stainless drilling.
When drilling holes deeper than 3x the diameter:
Use peck drilling cycles (drill in small increments, retract, clear chips)
This prevents chip packing and reduces work hardening
| Mistake | Solution |
|---|---|
| Using general-purpose HSS | Upgrade to cobalt or carbide |
| High RPM without coolant | Use slower speeds + lubricant |
| Forcing the bit | Maintain steady, controlled feed |
| No chip clearance | Use peck drilling + good flute design |
A: Technically, yes—but you’ll overheat and wear your bit fast. Always use coolant or cutting oil for best results.
A: Look for discoloration, squealing, or increased feed pressure. Replace or resharpen before damage worsens.
A: Yes, especially for larger diameters (>10mm) to reduce the initial cutting force.
Stainless steel doesn’t have to destroy your tools. If you pair the right drill bit (material + geometry) with smart technique and proper cooling, you’ll extend tool life, reduce defects, and improve your overall efficiency.
Whether you’re running a CNC line or supplying tools to workshop clients, choosing the right bit makes the difference.
Need help choosing bits for your application?
Reach out to our technical sales team for bulk quotes, samples, or OEM solutions.
ISO 9001:2015 certified | Suitable for 304, 316, and other austenitic stainless grades
Contact our experts today for a free quote or technical consultation.