Drilling hardened steel, stainless sheet, or cast iron asks more from a bit than most home jobs do. The right set saves time, cuts wandering, and gives you a cleaner hole with less drama at the drill press or in a hand drill. You also want a set that fits your usual hole sizes, storage habits, and the kind of metal you handle most. That’s where these eight picks come in.
The Shortlist At A Glance
IRWIN M35 Cobalt Drill Bit Set 29-Piece
CaRoller Cobalt Drill Bit Set 29-Piece
RCINDUS 1/4-Inch M35 Cobalt Drill Bits 15-Pack
WildBossy M35 Cobalt Drill Bit Set 20-Piece
SS SHOVAN M35 Cobalt Step Drill Bit Set 3-Piece
Pro Edge Technology M35 Cobalt Drill Bits 13-Pack
AIMLENTOOL M35 Cobalt Drill Bit Set 13-Piece
EZARC M35 Cobalt Step Drill Bit
More Details On Our Top Picks
The IRWIN set takes the broadest, most flexible approach in this group, with sizes from 1/16 inch to 1/2 inch in 1/64 inch steps. That matters in metalwork because small sizing jumps help you match fasteners, pilot holes, and cleanup work more closely than a bare-bones kit. The 135 degree split point is meant to reduce walking, so the bit starts with less skitter on smooth steel. For most garage users, that’s a practical balance of range and control.
Compared with the narrower sets from RCINDUS and AIMLENTOOL, this one covers more of the mid-to-large hole range without forcing you into a second purchase. The trade-off is simple, the larger assortment takes a bit more drawer space, so it suits a bench setup better than a pocket tool roll. Nothing flashy here, just a straightforward cobalt set that makes sense for general maintenance, brackets, and common fabrication tasks.
Strong Points
- Broad sizing handles many metal jobs.
- 1/64 inch steps give finer hole matching.
- Split point helps the bit start cleaner.
- Works well as a main shop set.
Things To Consider
- The full range takes more storage room.
- Large sets can slow down quick grab-and-go work.
Core Details
Who It Suits Best
You get the most from this set in a home shop or small fabrication space where one case needs to cover many hole sizes.
A Better Fit Elsewhere
RCINDUS 1/4-Inch M35 Cobalt Drill Bits 15-Pack suits you better when you keep drilling the same 1/4-inch hole size over and over.
CaRoller gives you the same 29-piece style of coverage, but the included cup-style holder changes the day-to-day experience. A tidy holder keeps the set easier to sort on a busy bench, especially when you’re swapping between sheet metal, plastic, and lighter steel work. The round shank is a familiar shape for standard chucks, so setup stays simple in common drills.
That practicality makes it a good match for a garage shelf or a small job box, though the listing language around returns and shipping reads like a marketplace note rather than a feature. Compared with IRWIN, the appeal here leans more toward storage convenience than fine size stepping. It’s a sensible pick for someone who values organization as much as the bits themselves.
What We Like
- Cup holder helps keep sizes grouped.
- Round shank suits common drill chucks.
- 29-piece count gives broad task coverage.
- Good fit for mixed material work.
Worth Noting
- Holder convenience matters more than premium finish details.
- Storage accessory adds bulk to the kit.
- Marketplace wording leaves the feature set less polished.
Feature Snapshot
Made For
You’ll like this most in a garage, utility room, or job trailer where quick sorting matters and the case has to stay orderly.
Where A Sibling Pick Shines
IRWIN M35 Cobalt Drill Bit Set 29-Piece suits you better when you want finer size steps across the full range.
RCINDUS focuses on one size and leans into repetition, which is handy in fabrication work where you keep opening the same holes. The 1/4-inch diameter is the headline here, and the 15-pack gives you enough backups for a workflow that chews through consumables. A plastic case is included too, so storage stays more controlled than tossing loose bits into a drawer.
Compared with the broader IRWIN and CaRoller sets, this is much more specialized, but that focus is also the point. The trade-off is obvious, you sacrifice size variety for a stack of the same dimension. You may find that very useful on a bench where one size does most of the work and repeatability matters more than range.
Best Bits
- 15-pack format suits repeat drilling.
- 1/4-inch size is clear and focused.
- Plastic case helps protect the set.
- M35 cobalt construction fits harder stock better.
Areas To Watch
- You give up size variety for quantity.
- Best value shows up only for repeated 1/4-inch work.
Technical Sheet
Right Fit For
This suits you best in metal shops, maintenance carts, or install work that keeps calling for the same diameter.
A Better Fit Elsewhere
WildBossy M35 Cobalt Drill Bit Set 20-Piece fits you better when you need more size variety for different fasteners and hole widths.
WildBossy sits in a useful middle ground, with a 20-piece spread from 1/16 inch to 1/2 inch and a jobber length shape that works well for everyday drilling. Jobber length means the bit has a standard longer body, which helps with reach in common tasks without turning it into a specialty tool. The index storage case is a real advantage too, especially in a workshop where missing pieces slow everything down.
That makes it a smart choice for a general tool drawer, though it does not offer the ultra-fine 1/64-inch stepping of IRWIN. The set feels aimed at people who want broad coverage without carrying a bigger 29-piece kit. A little less granularity is the trade-off, but the storage and range are nicely balanced for most home and light pro use.
Highlights
- 20-piece lineup covers many common sizes.
- Jobber length fits standard drilling jobs.
- Index case keeps pieces easier to sort.
- Range runs from small pilot sizes to half-inch work.
Minor Gripes
- No ultra-fine size stepping like some larger sets.
- Case organization matters, since missing slots slow setup.
Details At A Glance
Built With In Mind
You’ll get the most from this set in a home workshop or service truck where broad coverage and organized storage both matter.
Another Choice May Suit
IRWIN M35 Cobalt Drill Bit Set 29-Piece suits you better when you want finer increments across a wider selection.
This set shifts away from ordinary twist bits and into step drilling, which means each bit is shaped to enlarge holes in stages rather than all at once. That style is useful for sheet metal, aluminum, plastic, and stainless work where a stepped profile helps keep openings cleaner and more controlled. The TiAlN coating is there to help the bit surface hold up better in demanding use, though the real payoff shows up most on thin stock and panel jobs.
Compared with the straight twist sets from IRWIN or WildBossy, this is the more specialized tool, and that specialization is why it stands out. The 1/4 inch to 7/8 inch range covers useful steps for enclosure work, automotive panels, and light fabrication. For most home toolboxes, it’s not the first cobalt set to buy, but it can become the one that gets used more than expected.
Upsides
- Step shape helps manage hole enlargement.
- Useful for sheet metal and panel work.
- TiAlN coating adds a tougher surface layer.
- Three-piece format keeps the kit compact.
Points To Note
- Step bits solve a different job than standard twist bits.
- The range suits thin material better than deep drilling.
- Compact sets need careful storage to avoid mix-ups.
Feature Rundown
Who Will Love This
You’ll appreciate this most for metal panels, light fabrication, and jobs that need controlled enlargement instead of a single large plunge.
Look Elsewhere When
IRWIN M35 Cobalt Drill Bit Set 29-Piece suits you better when you need a broader spread of ordinary twist sizes for general drilling.
Pro Edge Technology keeps the set trim, which helps a lot when you want a smaller case and a tighter size spread. The 1/16 inch to 1/4 inch range makes sense for pilot holes, lighter hardware, and smaller metal jobs where a giant assortment would just sit untouched. The 135 degree tip is another practical touch, because that split style is built to help the bit start with less wandering.
Unlike the larger IRWIN and CaRoller sets, this one is easier to tuck into a drawer or carry alongside a compact drill kit. The index storage box matters here, since a small set gets frustrating fast when pieces go missing. For weekend repairs, cabinet hardware, and small steel brackets, it feels nicely targeted without extra clutter.
Bright Spots
- Small case fits compact storage spaces.
- Useful span for pilot and light-duty holes.
- 135 degree tip supports cleaner starts.
- Index box helps keep sizes orderly.
Small Caveats
- Smaller range may leave you wanting larger sizes.
- Better for lighter metal work than broad fabrication.
Core Details
The Right Fit
You’ll benefit most from this in a small shop, apartment tool kit, or light repair setup where space matters more than huge size coverage.
Where A Sibling Pick Shines
WildBossy M35 Cobalt Drill Bit Set 20-Piece suits you better when you need more middle-range sizes for broader shop work.
AIMLENTOOL lands in a very practical middle zone, with a 13-piece range from 1/16 inch to 1/4 inch. That keeps it small enough to manage easily while still covering many of the holes you make in hard metal, plastic, and wood around the house or in a light workshop. The jobber length shape gives you a familiar standard profile, which makes it easier to keep this set in regular rotation.
Compared with the tighter Pro Edge Technology kit, this one feels a little more everyday and a little less specialized in presentation. It’s a smart fit for people who want a compact set without feeling boxed into tiny pilot work only. The honest read is that the size range is modest, yet plenty of households will find that enough for routine maintenance.
Reasons To Buy
- Useful everyday size spread.
- Compact enough for most tool drawers.
- Jobber length suits common drills.
- Works across several typical material types.
Room For Improvement
- Range stops at smaller hole sizes.
- Larger fabrication jobs need another set.
Feature Card
Whose Shelf It Belongs On
You’ll get the most use from this in a household tool shelf, small repair kit, or starter workshop with modest drill needs.
Where A Sibling Pick Shines
IRWIN M35 Cobalt Drill Bit Set 29-Piece suits you better when you want the broader spread that covers more hole sizes.
EZARC goes in a different direction again, using a spiral flute step bit with a 1/4 inch hex shank instead of a standard twist profile. A hex shank is the six-sided end that grips more firmly in compatible chucks, which can be helpful during quick bit changes and panel work. The 1/4 inch to 3/4 inch range makes it especially suited to sheet metal, aluminum, plastic, and stainless jobs where gradual hole growth feels cleaner than forcing a large twist bit through in one pass.
Compared with SS SHOVAN, this one narrows in on the same step-bit idea but pairs it with a more tool-friendly shank shape for some setups. The trade-off is that it’s still a specialized bit, so it won’t replace a broad cobalt set like IRWIN or WildBossy. For enclosure builders, maintenance techs, and anyone who works through thin material often, it brings a focused kind of convenience.
Positives
- Spiral flute shape supports smoother chip clearing.
- Hex shank gives a secure grip in compatible tools.
- Step format suits panel enlargement work.
- Good fit for thin stock and enclosure tasks.
Honest Caveats
- Specialized shape limits it as a general-purpose bit.
- Better for sheet material than deep-hole drilling.
- Needs the right chuck style for best convenience.
Spec Overview
Best Suited To
You’ll appreciate this most for thin metal, aluminum, and plastic work where a stepped opening is more useful than a standard twist hole.
Reach For A Different Pick When
SS SHOVAN M35 Cobalt Step Drill Bit Set 3-Piece is the better match when you want a small multi-bit step set with a wider package of tools.
How To Choose The Right Cobalt Drill Bits For Metal
Start With The Metal You Drill Most
Mild steel, stainless steel, cast iron, and aluminum all ask for slightly different handling. Stainless and cast iron usually reward a harder cobalt mix, while softer materials can get by with less aggressive geometry and a smaller kit. That’s why a set like IRWIN works well for mixed household and shop use, while a more focused option like RCINDUS makes sense for repeat 1/4-inch work.
Material match matters more than flashy packaging. You want the bit body, point shape, and size spread to line up with the stock on your bench, not the logo on the case.
Match The Bit Style To The Job
Twist bits are the everyday choice for general drilling, especially in jobber length form, which gives you a standard body for common reach. Step bits, like SS SHOVAN and EZARC, are better for opening sheet material in stages, especially when a clean, controlled enlargement matters more than raw depth. The trade-off is simple, step bits are specialized tools, not all-purpose replacements.
Think about your usual work before the size chart. A garage user fixing brackets wants something different from someone drilling appliance panels or enclosure plates.
Check The Small Details That Affect Use
Split points, often shown at 135 degrees, help the bit start with less wandering on metal surfaces. Shank shape matters too, since round shanks fit standard chucks and hex shanks can grip more securely in compatible tools. Storage is worth attention as well, because index cases and holders make real life easier the moment a set grows past a few pieces.
The honest read is that the best kit is often the one you can reach, sort, and return to its place without thinking too hard. That calm, tidy routine saves more time than most people expect.
Choose Size Coverage With Restraint
Larger sets give you flexibility, but only to a point. A 29-piece set like IRWIN or CaRoller suits a mixed shop, while a 13-piece kit is easier to store and faster to sort for lighter duty work. You do not need every diameter on day one, just the range that fits your actual drilling pattern.
That’s the balancing act, coverage versus clutter. Pick the set that matches the holes you make most often, and the rest stays simple.
Things Worth Knowing First
Wrong Turns To Avoid
Many shoppers chase a huge piece count without checking the size spread. A pile of tiny increments helps only when you actually need them, and a too-narrow range can leave you short for brackets, plates, or panel work.
Another common miss is choosing a step bit for general drilling or a twist set for hole enlargement jobs. Match the tool to the task, and the set starts making sense much faster.
The Upgrade Payoff
Higher-tier cobalt sets often spend more on better size coverage, tighter organization, and more purposeful geometry. That usually shows up as a more useful case, a cleaner point shape, or a coating that supports harder use on metal surfaces. You’re paying for fewer compromises, not magic.
The upgrade earns its keep when you drill often, work in tougher metals, or hate replacing loose, mismatched bits. For occasional household repairs, a simpler set can still be the smarter call.
Frequently Asked Questions
What Does M35 Mean In Cobalt Drill Bits?
M35 refers to a high-speed steel blend that includes cobalt. That extra cobalt content is used for harder drilling tasks and tougher metals.
Are Step Drill Bits Better Than Twist Bits?
They serve different jobs, so neither one replaces the other completely. Step bits are better for enlarging thin material in stages, while twist bits are the general-purpose choice.
Does A 135 Degree Point Really Matter?
It can help the bit start with less wandering on metal. That’s useful on smooth surfaces where a bit tends to skate before it bites.
What Size Range Works Best For A Small Shop?
A compact range from 1/16 inch to 1/4 inch covers many light tasks and pilot holes. A broader set helps more once you start doing brackets, plates, and mixed repair work.
Why Does Storage Case Design Matter?
A good case saves time because each bit has a place. It also helps you notice missing pieces before the set turns messy.
Closing Remarks
For cobalt drill bits for metal, the right choice usually comes down to one thing, how you actually work. A broad set like IRWIN suits a mixed bench, while RCINDUS or AIMLENTOOL feels better when you keep reaching for smaller, repeat sizes. Step bits from SS SHOVAN and EZARC make sense for panel and sheet work, not every job in the shop. Match the shape, size spread, and storage style to your routine, and the set will feel useful from day one.
