If you've ever tried drilling stainless steel with a standard HSS (High-Speed Steel) bit and ended up with a glowing-hot, dull tool—you're not alone. This is one of the most common mistakes we see in both workshops and job sites. So let's get right to the point:
Yes, HSS drill bits can be used on stainless steel, but not all HSS bits are created equal—and without the right approach, you’ll ruin the bit and the workpiece.
Let’s break down why stainless steel is so challenging, which types of HSS bits are suitable, and how to drill it successfully without destroying your tools.
Stainless steel is known for its corrosion resistance and strength, but it's also:
Tough and work-hardening, which means it becomes harder the more you drill it.
Heat-sensitive, which can quickly dull or burn out a bit if not cooled properly.
Low in thermal conductivity, meaning heat stays concentrated at the cutting edge.
These characteristics make stainless steel a very unforgiving material when using general-purpose HSS bits.
According to tooling manufacturer Dormer Pramet, high-speed steel bits are appropriate only when:
The bit is cobalt-alloyed (M35 or M42 grade).
You drill at the correct speed and feed rate.
Lubrication is used throughout the process.
You’re drilling relatively thin stock or doing light-duty work.
So, if you're using basic HSS bits meant for wood or aluminum—don’t even try. They’ll lose their edge quickly, heat up, and possibly snap.
Cobalt drill bits are made from M35 (5% cobalt) or M42 (8% cobalt) high-speed steel. These materials:
Withstand higher temperatures without softening.
Offer longer tool life in hard metals.
Are ideal for stainless steel, cast iron, and titanium.
View Our HSS-Co Cobalt Drill Bits Collection →
Premium-grade cobalt bits, precision-ground for metal drilling applications.
Stainless steel is slick and hard. Use a center punch to prevent the bit from wandering.
Speed kills—literally, in the case of your HSS bit. Use a lower RPM:
6–10 m/min (roughly 100–150 RPM for 8mm bit)
Refer to the Machinery's Handbook or Sandvik tooling charts for optimal speeds.
Lubrication is non-negotiable. It:
Reduces friction and heat
Prevents work-hardening
Extends tool life
For stainless, high-viscosity cutting oil works better than water-based coolants.
Don’t force the bit. Use consistent pressure and peck drill—withdraw the bit every few seconds to clear chips and cool it.
If you’re dealing with:
Thick stainless steel (over 6–8mm)
Heavy-duty fabrication
High-volume production
You should seriously consider solid carbide bits or indexable drills instead. HSS is not designed for high-speed, high-load environments.
Can HSS drill bits be used on stainless steel? Yes—but only the right kind, and only with the proper technique.
If you're serious about getting clean holes and extending tool life, invest in cobalt HSS bits and follow best practices.
Cut corners, and you'll end up with a pile of burnt-out bits and ruined workpieces.
Contact our experts today for a free quote or technical consultation.