Best Drill Bits for Metal

Quick Picks: The Best Bit Types for Common Metal Jobs

If you want the “tell me what to buy” version first, here’s the cheat sheet. Then we’ll explain the why.

For most DIY metal drilling (mild steel, brackets, angle iron): HSS with a split-point tip

A quality HSS (high-speed steel) set with a 135° split point is usually the best value.
It starts cleaner (less “walking”), drills faster, and handles the everyday metal stuff most people run into:
hardware-store steel, thin plate, punched angle, and mixed materials.

For stainless steel and tougher alloys: Cobalt (M35 or M42)

Stainless work-hardens when you rub it instead of cutting itso you want a bit that tolerates heat and stays sharp.
Cobalt drill bits (often labeled M35 or M42) are the typical upgrade when stainless,
cast iron, or other hard metals are on the menu.

For sheet metal, electrical knockouts, and “one bit, many hole sizes”: Step drill bits

Step bits are excellent for thin metalthey can enlarge holes gradually and often leave a cleaner result
with less grabbing. They’re also handy for deburring as you go.

For repeated production-style drilling or very hard metals: Carbide (with the right setup)

Carbide is extremely hard and can be amazing in the right conditions, but it’s less forgiving and not always ideal
for casual handheld drilling. Think “high performance,” not “oops, I drilled at an angle.”

How to Choose Drill Bits for Metal

Choosing the best drill bits for metal is mostly about matching three things:
bit material, tip geometry, and the metal’s personality
(yes, metals have personalitiesstainless is the stubborn one).

1) Match the bit material to the metal

• HSS (High-Speed Steel): Great for general-purpose drilling in mild steel, aluminum, and thin metals.
  It’s the “reliable daily driver.”
• Cobalt HSS (M35/M42): More heat-resistant and wear-resistantbetter for stainless steel,
  tougher steels, and long drilling sessions where heat builds up.
• Carbide: Extremely hard and long-wearing, often used in machining and production contexts.
  Awesome when the setup is rigid; less fun when the workpiece or drill is wobbling.

2) Don’t ignore the point angle

You’ll commonly see 118° and 135° tips. For metal drilling,
many people prefer 135° split-point bits because they start more accurately and reduce wandering.
In plain English: fewer “oops” scratches and fewer off-center holes.

3) Consider coatingsbut don’t treat them like magic dust

Coatings can help with heat, friction, and corrosion resistance, but they don’t replace good technique.
A coated bit drilling too fast can still overheat. A fancy bit used like a butter knife still won’t cut.
Think of coatings as a performance bonus, not a permission slip to abuse your tools.

4) Pay attention to the shank

If you’ve ever watched a bit spin in the chuck while making that sad “eeeeek” noise, you already care about shanks.
Bits with 3-flat shanks reduce spin-out in the chuck. Hex shanks are convenient for quick changes,
but for heavy metal drilling, a solid chuck grip matters.

Top Drill Bit Types for Metal (And When to Use Each)

HSS jobber bits: the everyday metal drill bit

“Jobber length” is the standard length you’ll see in most sets. A good HSS jobber bit set can cover a ton of metal tasks:
drilling pilot holes, enlarging holes, and working through mixed materials (like a steel bracket attached to wood).
For mild steel and aluminum, HSS is often all you need.

Black oxide HSS: solid budget performance

Black oxide finishes are popular because they provide some corrosion resistance and can improve chip flow.
If you’re drilling “normal” metal occasionally, black oxide HSS can be a smart balance of cost and performance.

Titanium-coated HSS: great for lighter metal work

Titanium-coated HSS bits are widely used for general drilling and can last longer than plain HSS in many scenarios.
They’re commonly recommended for softer metals (and mixed materials), but they’re not the go-to choice for stainless
when you’re pushing into tougher jobs.

Cobalt (M35/M42): the stainless steel problem-solver

Cobalt bits are the upgrade you reach for when the metal is hard, heat is building, and regular HSS taps out early.
Look for labeling like M35 (often ~5% cobalt) or M42 (often ~8% cobalt).
These are popular picks for stainless, cast iron, and other demanding materials.

Step drill bits: sheet metal’s best friend

Step bits are cone-shaped bits with “steps” that increase in diameter.
They shine in thin metal because they drill gradually, often reducing grabbing,
and they can leave a cleaner edge than a standard twist bit when you’re enlarging holes.
They’re also handy for electrical work (like panels and boxes) where you want multiple hole sizes without swapping bits.

Special mention: “mechanics length” bits for tighter control

Shorter bits can be easier to control and may flex less. If you’re drilling in tight quarters or want more accuracy,
mechanics-length bits can help. They’re not a different “material,” but the length can make the job feel easier.

How to Drill Metal Without Killing Your Bits

You can buy the best drill bits for metal and still ruin them in minutes if you drill too fast, don’t clear chips,
or let the metal overheat. The goal is simple: cut, don’t rub.

Safety first (quick and real)

• Wear eye protectionmetal chips don’t care about your weekend plans.
• Secure the workpiece so it can’t spin or shift.
• Keep hands clear of sharp edges and hot chips.

Use a center punch (or a split point) to prevent skating

Metal is smooth; bits like to wander. A center punch gives the tip a place to start.
If you’re using a split-point bit, you may still benefit from a punch on harder metals or glossy surfaces.

Speed matters more than most people think

A common mistake is drilling metal like it’s wood: high speed, light pressure, and lots of noise.
For many metals, you want a slower RPM and steady pressure so the bit forms chips.

A classic rule for converting cutting speed to RPM is:
RPM ≈ (SFM × 3.82) ÷ bit diameter (in inches).

Example: If you’re drilling steel with a 1/4-inch bit and you aim around 90 SFM, your RPM is roughly
(90 × 3.82) ÷ 0.25 ≈ 1375 RPM. For stainless (often lower SFM), the RPM drops.

Use cutting oil (especially on stainless)

Cutting oil reduces friction and heat. Heat is what makes bits dull fast and can cause stainless steel to harden
at the surfaceturning your project into a tiny, angry anvil.

Peck drilling: the simple habit that saves bits

Instead of pushing straight through in one go, drill a bit, back out to clear chips, then continue.
This helps chips escape and keeps the cutting edge cooler, especially in deeper holes.

A practical step-by-step approach (no drama version)

1. Mark the hole location (use a punch if needed).
2. Clamp the metal securely.
3. Start with a smaller pilot hole if the final size is large.
4. Run a slower speed than you’d use for wood.
5. Add cutting oil and “peck” to clear chips.
6. Ease pressure near breakthrough to reduce grabbing and burrs.

Common Problems (And Fixes That Actually Work)

Problem: The bit “walks” and scratches the metal

• Fix: Use a center punch, a 135° split-point bit, or start with a smaller pilot hole.
• Fix: Start slower until the bit establishes a groove.

Problem: The bit squeals, smokes, or turns blue

• Fix: Reduce RPM and use cutting oil.
• Fix: Apply steady pressure so the bit cuts and makes chips (not dust).

Problem: Stainless steel feels “impossible”

• Fix: Switch to cobalt (M35/M42).
• Fix: Use slower speed, cutting oil, and don’t let the bit rub in place.

Problem: The bit grabs when it breaks through

• Fix: Lighten pressure as you near the backside.
• Fix: Use a backing material (when appropriate) and keep the workpiece clamped.

Problem: Oversized or sloppy holes

• Fix: Use a shorter bit for better control or step up sizes gradually.
• Fix: Avoid wiggling the drilllet the bit do the geometry.

Care, Sharpening, and When to Replace Bits

Store bits like you want them to stay sharp

Tossing drill bits into a drawer is how sharp edges meet other metal objects and lose the fight.
Keep them in a case, indexed holder, or at least separated so cutting edges don’t bang together.

Yes, you can sharpen many metal bits

HSS and cobalt bits can often be sharpened (especially if you have a sharpener or know the angles).
If a bit is chipped, badly overheated, or bent, it’s usually better to replace it.

Know when the “best drill bit” is the fresh one

A dull bit makes heat. Heat makes bits dull faster. That’s a tool tragedy in two acts.
If you’re pushing harder, getting squealing, or seeing discoloration quickly, the bit may be past its prime.

FAQ

Are cobalt drill bits always better than titanium-coated bits?

Not always. For general metal drilling, a good HSS or titanium-coated HSS set can be plenty.
Cobalt shines when the metal is harder (like stainless) or when heat resistance matters more.

What’s the best point angle for drilling metal?

Many metal-focused sets use a 135° split point because it starts more precisely and reduces walking.
That said, technique and correct speed matter just as much as the number stamped on the package.

Do I really need cutting oil?

For many metalsespecially stainlessit’s a big help. Cutting oil can reduce friction and heat,
which protects the bit and improves the hole quality.

What’s the easiest way to drill clean holes in thin sheet metal?

Step drill bits are often the easiest option for thin sheet metal because they enlarge gradually
and can reduce grabbing while leaving a cleaner edge.

500+ Words of Real-World Experiences: What Usually Happens in the Wild

The internet loves clean, perfect demos where a brand-new bit glides through metal like it’s slicing warm brownie.
Real life is… less cinematic. Here are common “field experiences” people run into when choosing the best drill bits for metal,
plus what typically separates a smooth job from a chaotic one.

Experience #1: “My bit is sharp, so why is it just polishing the metal?”

This happens constantly with stainless steel. Stainless has a sneaky habit: if you drill too fast or too lightly,
the bit rubs instead of cutting, heat rises, and the surface can become harder right where you need it softer.
The result feels like you hit an invisible force field. People often respond by pressing harder at high speed,
which is basically the tool equivalent of yelling at your phone battery.
The fix that usually works is the boring one: slow the speed down, use cutting oil, and apply steady pressure so the bit makes chips.
If the bit is a basic HSS and you’re drilling a tougher stainless, switching to cobalt (M35/M42) is often the “why didn’t I do this earlier?” moment.

Experience #2: “The bit skated across my nice clean panel and now it looks like modern art.”

On smooth metal (especially thin sheet), the first second of drilling decides everything.
If the bit tip can’t bite, it wanders. That’s why split-point tips and center punches get recommended so often.
Many people also discovermid-scratchthat starting at full speed is a bad plan.
A slower start helps the tip establish a tiny groove before you bring the drill fully into the cut.
For sheet metal, step bits can feel like cheating in a good way because they tend to track better and enlarge gradually.

Experience #3: “I drilled the hole, but the back side looks like it got attacked.”

Breakthrough is where metal likes to grab. The bit is about to exit, the remaining material is thin,
and the drill can lurch. People often see a nasty burr, an oval-ish exit, or a sudden “catch” that surprises them.
The most common improvement is simply easing off pressure right before the bit exits.
If you’re drilling thin stock, backing the workpiece with scrap material (and clamping everything) can reduce blowout and burrs.
Step bits also help here because they don’t “punch through” the same way a large twist bit can.

Experience #4: “I bought a cheap set and now every bit is missing its soul.”

Cheap bits can work for very light jobs, but metal drilling exposes weaknesses fast:
soft steel dulls quickly, poor grinding geometry causes wandering, and inconsistent sizing creates sloppy holes.
Many DIYers end up with the same pattern: a budget set for rough work, then a small collection of higher-quality bits
in the sizes they use most (often 1/8″, 3/16″, 1/4″, and the common larger sizes).
That “core sizes done well” approach is often more satisfying than owning 200 mediocre bits you don’t trust.

Experience #5: “My best results came from technique, not the fanciest bit.”

This is the quiet truth. A quality bit helps, but technique is what keeps it alive:
correct speed, cutting oil, chip clearing, and a stable setup. People who get consistently clean holes usually do the same
small things every time: mark the hole, secure the piece, start controlled, and avoid overheating.
The “best drill bits for metal” are absolutely worth buyingbut they perform best when you treat metal drilling like metal drilling,
not like wood drilling with extra confidence.