Our readers keep the lights on and my morning glass full of iced black tea. As an Amazon Associate, I earn from qualifying purchases.
Specs are compiled from manufacturer listings and verified buyer reviews and can change over time — please confirm the key details on the product page before buying.
If you have ever watched a cheap drill bit spin and smoke on a piece of steel without making a dent, you already know the real problem: the bit, not your drill. The right bit drills a clean hole in seconds; the wrong one dulls and scratches the workpiece. This guide covers eight steel-drilling sets, sorted by what each one does best.
I’m Min — the founder and writer behind Gadgets Feed. This guide is built by comparing the manufacturers’ published specifications and the patterns across verified customer reviews, so you get each pick’s real strengths and trade-offs instead of marketing spin.
The sections below break down the materials, point angles, and coating types that decide whether a bit survives stainless steel or gives up halfway through. By the end you will know which bits for drilling steel match your drill and your material.
Our Picks at a Glance
How To Choose The Best Bits For Drilling Steel
Steel is unforgiving. A bit that glides through pine will burn and dull on a steel plate if the material, point angle, and coating are not matched to the job. Here are the three things that decide whether a set earns its place in your toolbox.
Material: M35 Cobalt Versus Standard HSS
High-speed steel (HSS) is the baseline — it handles mild steel, aluminum, and wood fine. Add 5% cobalt and you get M35, a harder alloy that holds its edge longer in stainless and cast iron. If your work is mostly mild steel and general repair, standard HSS is enough. If you regularly touch stainless or hardened alloys, cobalt is the safer bet — and you will feel the difference in how long the edge lasts.
Point Angle And Tip Geometry
A 135-degree split point is the standard for metal. The wider angle compared to the 118-degree woodworking tip keeps more of the cutting edge in contact with the steel, and the split notch at the tip lets the bit start cutting without skating across the surface. That self-centering behaviour is why you can skip the center punch on most jobs. Some sets also use a pilot point or spear point — those bite on contact and pull the bit into the material.
Flutes, Shank, and Case
Flutes are the spiral grooves that carry chips out of the hole. Two flutes is the norm for twist bits — enough clearance for steel without weakening the body. The shank is the part your chuck grips; a round straight shank fits any standard chuck, while flatted or hex shanks resist slipping in a keyless chuck. Finally, the case matters more than most buyers expect — a metal index with stamped sizes outlasts a plastic one, and a loose or damaged case means scattered bits and unreadable labels.
Quick Comparison
| Model | Best For | Material | Pieces | Point Angle | Amazon |
|---|---|---|---|---|---|
| Champion Brute Platinum TWISTER-XL28★ Best Overall | Serious steelwork and stainless | HSS | 29 | 135° | Amazon |
| RCINDUS 3/16″ Cobalt 20-PieceBest Value | Bulk 3/16″ holes and DIY repair | Cobalt | 20 | 135° | Amazon |
| MACXCOIP Metric 19Pcs M35 CobaltPrecision Pick | Metric sizing and precision work | Cobalt Steel | 19 | 135° | Amazon |
| STROTON Cobalt 6 Series 17PCS | Stainless steel and hardened metal | Cobalt | 17 | 135° | Amazon |
| COMOWARE 21Pcs M35 Cobalt | All-round metalworking value | HSS | 21 | 135° | Amazon |
| CaRoller 29Pcs Black and Gold | Soft metals, wood, and plastic | HSS | 28 | 135° | Amazon |
| DEWALT DW1369 Titanium Nitride | Clean pilot holes and everyday drilling | Titanium Nitride Coated | 29 | 135° | Amazon |
| IRWIN 3018005 HSS 29-Piece | Heavy truck and automotive repair | HSS | 29 | 135° | Amazon |
In‑Depth Reviews
1. Champion Cutting Tool Brute Platinum 29 Piece 1/16-1/2″ x 64ths HSS Mechanics Length Twister-XL28 Drill Bit Set-135 Degree Split Point
Our pick — over 4.5★ from 500+ verified ratings; the strongest balance of quality and price.
The mechanics-length workhorse that flexes where cobalt snaps and drills through stainless without flinching.
If you drill steel regularly and are tired of watching cheap bits chip or shatter, this is the set to look at first. Champion builds the TWISTER-XL28 from premium high-speed steel with a NOMO surface treatment for longer tool life, and the mechanics-length design keeps the overall bit shorter so it stays rigid in the chuck. Compared to a standard 29-piece set with a 1.59 mm minimum diameter, this one goes down to a 0.06 inch minimum bore diameter — a genuinely fine starting size.
The 135-degree split point is self-centering, so the bit bites the metal on contact instead of skating across the surface and scratching your workpiece. The flatted shanks lock into a keyless chuck fast, which matters when you are switching between pilot and final sizes mid-job. Buyers who work in automotive repair and fabrication keep coming back to this set — the sharpness holds up far longer than the box-store bits they replaced, and the cutting wax technique (slow speed, steady feed) keeps them punching clean holes in stainless.
The one thing to plan for is the shipping. A handful of owners have opened the box to find the plastic container cracked and bits loose in the envelope, and one mechanic reportedly spent an hour and a half sorting the set back into order with calipers and a magnifying glass.
Where it wins
- Flexes instead of chipping where cobalt bits snap, holding up in stainless and titanium alloys
- 135° split point self-centers, no center punch needed on most steel
- Flatted shanks grip a keyless chuck instantly, no slipping mid-job
- Quality is the aspect owners praise most, followed closely by cutting performance
The honest catches
- Packaging has arrived damaged for a few buyers, scattering bits in the envelope
- Value is the one thing owners split on — these cost more than basic cobalt sets
- Bit holder and lid tightness each drew mixed early feedback
Buy this if: you drill stainless, titanium alloys, or hardened steel regularly and want a set that survives the abuse.
Skip this if: you want the cheapest possible option for light DIY — the premium here is real.
2. (20PCS) 3/16″ Cobalt Drill Bit, HSS M35 Metal Drill Bits for Steel, Stainless Steel, Cast Iron, Hard Plastic and Wood
Twenty identical 3/16″ cobalt bits — the practical answer when one size handles almost every repair you tackle.
Most homeowners and weekend fixers burn through one or two sizes far faster than the rest of the set. That is the case for buying twenty identical 3/16″ (Dia 4.763mm) cobalt bits rather than a broad assortment. This is industry-grade M35 high-speed steel with 5% cobalt, which makes it harder than standard HSS and capable of biting into hardened metal. With 20 pieces in the pack versus 19 in the metric MACXCOIP set, you are getting the most units per set in this whole roundup.
The 135-degree split point gives automatic centering, so the bit does not walk on a stainless surface while you are trying to place your hole. Value and performance are the two things owners praise most about this set. One reviewer (in the box, verbatim) reports using theirs in a rotary tool to drill out a seized screw and seeing no visible wear next to a fresh bit from the package. That kind of edge retention is what cobalt buys you.
What it is not: a complete size range. If you need a 1/8″ or a 1/2″ hole, you will need another set alongside this one. The trade-off is the flip side of the value — you get depth in one size instead of breadth across many.
The math that matters: twenty identical bits means you can afford to be less precious about them. Snap one, grab the next.
Plan around it: pair this bulk pack with a small mixed-size set for the wider jobs — no single 3/16″ bit can cover a 1/2″ hole.
Great fit for: anyone whose steel drilling is mostly one or two common sizes and wants spares ready in the case.
Less useful for: projects that need a full graded range, since every bit here is the same diameter.
3. Metric 19Pcs(1.0mm-10.0mm) M35 Cobalt Drill Bit Set
A metric-grained cobalt set that tops out at 10.0mm — built for precision work, hobby benches, and small fabrications.
If your drill press or hand drill lives on measurements in millimeters, this set is the natural fit. The MACXCOIP set runs from 1.0mm to 10.0mm in nineteen steps of half-millimeter increments, giving you maximum versatility in a compact package. It is made from M35 cobalt steel with a 135-degree point and a two-flute twist design that clears chips faster than single-flute geometry. Compared with the Champion set above, the cutting geometry here is much finer at the small end — a 10 mm maximum diameter versus the Champion’s 1.59 mm starting point.
Owners rate the sharpness right out of the factory — “I got the 19 piece metric set. The bits are quite sharp from the factory,” one buyer put it. What is interesting is that the metal case surprises people too: several expected a flimsy plastic holder and opened the box to find painted metal instead. The bits cut through aluminum and mild steel quickly, and the size range covers most small machining and electronics work neatly.
The catch is that cobalt is tough but not bulletproof. Use them with cutting oil and a steady speed and they will hold up. Skip these if you are drilling a lot of stainless in the 1/2 inch range — that job needs a larger set with more body strength.
What earns its spot
- Half-millimeter metric steps from 1.0mm to 10.0mm — rare in a mid-priced set
- Metal index case surprised owners who expected plastic at this tier
- Value for money and sharpness are the two most-praised traits
- Two flutes clear chips fast on aluminum and mild steel
What to know going in
- Cobalt bits can snap on hardened metals if you force them or run off-axis
- Best results come with cutting oil and a deliberate feed rate
- Not built for heavy stainless plate work in the upper sizes
Best for: anyone whose measurements are metric and whose work is small-scale precision drilling.
Avoid it for: heavy steel plate work in the 1/2 inch range, where a beefier bit body matters more.
4. Cobalt Drill Bit Set (1/16-1/2 Inch, 17PCS), M35 High Speed Steel Twist Drill Bits for Stainless Steel, Hard Metal, Cast Iron, Plastic and Wood
A cobalt set with 68 HRC hardness that keeps biting when other bits have already given up on stainless.
What sets this set apart is the 68 HRC (Rockwell Hardness Scale) rating on its premium 5% cobalt steel — a measure of how hard the bit is and how well it resists heat, wear, and chipping when steel gets hot. The cutting edge is ground three times during manufacture, which is why owners see long curls of steel chip flying off instead of a slow grinding pass. Compared to a broader set like the Champion with its 1.59 mm minimum diameter, this one lands the same 0.06 inch minimum bore diameter but at a much lower tier of spend.
What reviews consistently underline: this set chews through stainless where other brands simply do nothing. Multiple 5-star owners describe walking away from pricier names and landing here. One reviewer (in the box, verbatim) reports the bit sliced stainless like butter after a well-known competitor set failed outright. For automotive work, welding repair, and anywhere stainless or hardened metal shows up, this set earns its keep.
Here is the honest bit: the durability feedback is split. While many owners say the bits stay sharp and take abuse, some have broken an individual bit under heavy torque — an expected risk with cobalt when the feed rate is too high. Also note the plastic case gets good marks for tight bit clamps and closure, but treat the cardboard shipping more carefully and you will avoid a bent index. Best if your work is stainless and hardened metal; think twice if you mostly drill soft materials where standard HSS costs less and lasts about the same.
Where reviewers land: the sharpness from the start surprises people — long steel ribbons rather than dust.
Know before you buy: this set’s 17 pieces cover common sizes, but a snapped bit is a real risk if you push hard without cutting oil.
The pick for: stainless, hardened steel, and cast iron jobs where edge retention is what matters most.
Not the pick for: hobbyists working only in soft metals or wood — the cobalt premium is wasted there.
5. COMOWARE Cobalt Drill Bit Set- 21Pcs M35 High Speed Steel Twist Jobber Length
Twenty-one graded cobalt bits that just chew through stainless, cast iron, and aluminium without complaint.
If you want one set for the whole bench — metal, plastic, wood, and the odd stainless fitting — this 21-piece COMAWARE range from 1/16″ to 3/8″ nails the middle of the road. The M35 high-speed steel body carries 5% cobalt, which adds wear, heat, and abrasion resistance over standard HSS bits. The 64-tooth range and consistent half-size increments cover the sizes a home fabricator actually reaches for. Compared to the metric MACXCOIP set’s 10 mm maximum diameter, this set is inch-graded and hits the same strong value story with a different sizing convention.
Cutting performance is the number-one thing owners praise most about this set, and it holds up under real work. Reviews describe drilling through heavy-gauge stainless and cast iron pipe without the bit dulling, and getting long ribbons instead of dust. The 135-degree self-centering point works correctly, and the twisted shank clears shavings so the bit does not clog mid-cut.
The recurring gripe is the index case. Some units arrive with a damaged holder and owners end up dropping the bits into an older case or a drawer. The bits themselves are consistently well-reviewed — it is the packaging that splits opinion. That said, the cobalt performance is the reason to choose this set, and the case issue is easy to work around if you already have a spare index in the shop. Pick this if you want broad inch coverage at a fair price; skip it if a flawless storage setup on arrival is a deal-breaker.
The winning traits
- Cutting performance is what owners praise most — stainless and cast iron both fall fast
- 21 graded sizes from 1/16″ to 3/8″ cover most routine metalwork
- 135° split point self-centers with minimal pressure
- Twisted shank clears chips cleanly, no mid-hole clogging
The honest caveats
- Index case arrives damaged for a handful of buyers
- Sharpness and durability are mixed — sharp from the start, edge retention depends on speed and feed
- Storage feedback is mixed — plan for a spare case if the included one is marginal
Buy this one when: you want inch-graded cobalt coverage for mixed metal, wood, and plastic work at a sensible tier.
Choose something else when: the storage case arriving in one piece is critical — it has been hit-or-miss.
6. CaRoller 29Pcs Drill Bit Set, 135 Degree Tip High Speed Steel
A full 29-piece range in black-and-gold finish — great on soft metals and wood, not built for serious steelwork.
Let’s be clear up front: the manufacturer of this set says directly that it is not recommended for hardened steel or stainless steel, and recommends speeds below 500 RPM for plastic. What the CaRoller set is genuinely good at is aluminium, copper, low-alloy steel, wood, and plastic — the soft-material jobs that make up a lot of home and remodel work. The set runs from 1/16″ all the way up to 1/2″ in 29 pieces, with a black oxide and amber coating for wear resistance and a 135-degree self-centering split point with a round straight shank. In size variety, nothing else in this roundup gives you as many different diameters.
Owners consistently sell this as a strong tool-bag set — sharp from the start, cuts aluminium studs cleanly, and worth the money for general work. The sharpness draws a lot of positive reaction, and the size coverage is genuinely useful when you do not know ahead of time what diameter a job will need.
The honest caveat: on steel, this set dulls fast. Reviews describe the bits dulling quickly and even burring badly enough on steel that they could not be put back in the index — that is the trade-off of the coating and edge geometry at this tier. If your target material is stainless, hardened steel, or thick cast iron, look at the cobalt sets higher on this list. If your world is aluminium, wood, plastic, and light-gauge sheet, the size variety earns its place.
Sized right for: general home drilling and soft-metal work, where having every diameter on hand matters more than edge longevity on hard steel.
Avoid it for: serious stainless or hardened-steel jobs — the manufacturer is clear about that limitation, and owner feedback agrees.
Makes sense for: household kits and aluminium, wood, and plastic projects where broad size coverage wins.
Does not make sense for: anyone whose primary target is stainless steel or hardened alloy — that job needs cobalt.
7. DEWALT Titanium Nitride Coated Drill Bit Set with Pilot Point, 29-Piece (DW1369)
The pilot-point set for clean starter holes — titanium nitride coating for longer bit life and no spin shanks for grip.
The DW1369 has one of the cleanest drilling personalities in this lineup. Titanium nitride coating (a hard gold-coloured surface layer that reduces friction and extends bit life) is the headline, and the pilot point starts on contact so holes come out clean with minimal pressure. The tapered web geometry adds durability to reduce breaking, and the no-spin shanks seat firmly in any chuck. The set runs 1/16 inch to 1/2 inch across 29 pieces in a tough storage case that hangs on a wall.
Owners use this set for wood and metal interchangeably — the same bit that cuts a clean pilot hole in pine will also take a bite out of stainless under pressure. The bit performance is the well-liked part, with value for money ranked right below it in what buyers praise. For a drill press or portable drill in a workshop where you switch between materials often, this is a set that just works.
The honest caveat: the case gets mixed reactions. Several owners find it hard to get bits out of the case, especially the rear row where the size labels are hard to read. A couple of buyers also note that some of their bits broke under heavy use — not a pattern, but worth knowing if you push torque hard. Reach for this if you want a self-centering pilot-point set and a name brand you recognise; look at the Champion or STROTON if your steel work is the priority.
Why it earns a spot
- Titanium nitride coating extends bit life versus uncoated HSS
- Pilot point starts on contact for clean holes without walking
- Tapered web design adds durability and reduces breakage
- No-spin shanks seat firmly in keyless and keyed chucks
What you are trading for
- Bit access from the case draws mixed feedback — tight holders and hard-to-read sizes
- A handful of buyers report broken bits under heavy torque
- Size holder on newer versions uses painted labels versus the old stamped set
Fits best when: you drill a mix of wood and steel and want a self-centering pilot point from a brand you already trust.
Consider skipping when: your work is dominated by stainless — read the cobalt sets above before locking this one in.
8. Irwin Tools IRWIN Drill Bit Set, High-Speed Steel, 29-Piece (3018005)
Three decades of shop-floor reputation in one black-and-gold 29-piece set, still the go-to for automotive and heavy-truck work.
The IRWIN 3018005 earns its following on trucks and in job-site garages, not in weekend hobby benches. Premium high-speed steel stands up to extended drilling in tough materials, and the black-and-gold oxide finish adds corrosion resistance for bits that live in a shop drawer between jobs. The 135-degree split-point tip starts on contact, cutting with less force and eliminating the walking that leaves scratches across a workpiece. The set runs 1/16″ to 1/2″ in 1/64″ increments across 29 pieces, with hex flats above the 3/8″ bits to stop chuck slippage on the big sizes.
What owners value most is the money-to-performance ratio — drilling performance and sharpness both rank high, and reviewers describe clean cuts through thick metal with minimal heating. Industrial mechanics use these on semi-truck repairs and report the bits resist the heat and snap that cheap sets show under the same load. Sharpening a worn IRWIN brings it right back, which stretches the working life further.
The catch is the case. Owners describe the metal index as stiff and awkward — a couple of buyers specifically recommend transferring the bits to a hard plastic case for daily use. Durability is also split, with a handful reporting a broken bit within a day of first use, likely from too much feed pressure. Reach for this set if your shop is automotive or heavy equipment and you need bits that hold an edge through a full day’s drilling; pass on it if you want a smoother case for kitchen-drawer storage.
What makes it work: sharpness from the start, hex flats for big bits, and black oxide resistance to corrosion — an industrial set that keeps delivering on trucks and in shops.
Plan for: swapping the bits into a plastic case if the included metal index feels as stiff to you as it has to other owners.
Best suited to: mechanics, fabricators, and heavy-equipment work where edge retention over a long day matters more than a tidy case.
Not best suited to: casual DIY where a lighter-duty set would do the same job for a fraction of the spend.
Understanding the Specs
Cobalt Percentage and HRC
A cobalt drill bit carries a percentage of cobalt mixed into the high-speed steel — M35 typically contains 5% cobalt. That addition raises the hardness and heat resistance of the steel, so the bit holds its edge longer when it gets hot against stainless or hardened alloys. Hardness is measured on the Rockwell C scale (expressed as HRC); the higher the number, the more resistant the steel is to deformation. A bit with more cobalt and a higher HRC rating will stay sharp longer, but it is also more brittle — forcing it or running it off-axis can snap the tip.
Point Angle and Split Point
The point angle is the angle of the cutting tip when viewed from the side. A 135-degree point is standard for drilling metal because the wider angle keeps more of the cutting edge in contact with the surface, which lets the bit start cutting with less pressure. A split point adds a small notched grind at the tip that further improves centering, so the bit bites the metal instead of sliding across it. This is the difference between a bit that walks and scratches your workpiece and one that starts the hole exactly where you placed it.
Number of Flutes
Flutes are the spiral grooves running up the bit. Most steel-cutting twist bits — including all eight sets here — use two flutes. Two-flute geometry gives enough cross-sectional rigidity to take the torque of steel cutting while keeping a clear channel for chips. Three or four flute designs exist but are better suited to drilling cast iron or specific materials, and they have less room for chip evacuation.
Shank Type and Case
The shank is the smooth end that goes into your drill chuck. A round straight shank fits any standard chuck; a flatted or hex shank resists slipping when your chuck is keyless, and it allows faster bit swaps. The case — usually called an index — is graded storage. Metal index cases with stamped size markings outlast plastic ones and rarely develop the loose holders that send bits cascading across your workbench. Tight bit clamps and clear size labels save real time mid-job.
FAQ
What kind of drill bit do I need for stainless steel?
Is cobalt better than titanium nitride for steel?
What does 135-degree split point mean on a drill bit?
Do I need cutting oil when drilling steel?
How many pieces do I actually need in a drill bit set?
Can I use the same drill bits on wood and metal?
What sizes are included in a standard 29-piece set?
Why do cobalt drill bits break more easily than HSS?
Is a metal index case better than a plastic one?
Final Thoughts: The Verdict
For most people doing real steelwork, the bits for drilling steel pick is the Champion Brute Platinum TWISTER-XL28 — it flexes where cobalt chips, self-centers on every bite, and holds a USA-made edge through stainless, titanium alloys, and hardened steel. If your work centres on stainless and hardened metals at a value tier, the STROTON Cobalt 6 Series 17-piece delivers 68 HRC edge retention without the premium outlay. And for anyone whose measurements are metric — small fabrication, electronics, or a first precision set — the MACXCOIP Metric 19-piece M35 is the clear reach.
How We Picked
We do not accept paid placement. Every pick is matched to a real buyer and a real use-case; we do not hands-on test units.
Sources & Methodology
Specifications: manufacturer listings and product documentation. Review insights: verified customer reviews, as of September 2026. Pricing: not shown on this page (it changes often); check the current price via the retailer link.
As an Amazon Associate, Gadgets Feed earns from qualifying purchases. This does not affect which products we feature.