ReviewsCategoriesExplainedThe JournalHow we reviewAbout Affiliate disclosure

Explained

Hole Saws, Explained

After reading, you'll understand which arbor you need, what each cutting edge is genuinely rated for, and how to read a depth and speed spec before you buy.

Updated August 23, 2026 · Companion to our Tech & Gadgets review

In this guide

Almost everybody's first hole saw mistake is the same one. You buy a cup, you buy an arbor, and the two do not screw together, because the industry uses one thread for small saws and a different thread for large ones. The second mistake is running the thing at full drill speed, which cooks the teeth on a big saw in a couple of holes. Neither is a secret: the thread sizes and the recommended speeds are published. They are just published somewhere nobody looks until the third hole.

The 30-second version

  • There are two threads, not one, 1/2 in. x 20 for saws from 9/16 in. to 1-3/16 in. and 5/8 in. x 18 for 1-1/4 in. and larger, and a kit with one arbor only covers one of them.
  • The thread is standard, the quick-change is not, so cups and plain arbors mix across brands while proprietary mandrels and pin systems may need an adapter or may not accept the cup at all.
  • Depth of cut is usually about 1-5/8 in., which clears a single nominal two-by at 1-1/2 in. but not a doubled plate, and deep-cut and carbide ranges publish 2 in. or more.
  • Speed matters more than pressure, and both Milwaukee and LENOX publish recommended RPM by diameter and material, dropping well under 100 RPM for large saws in stainless.
  • Warranties in this category are thin, with Milwaukee's tooth break cover on HOLE DOZER the exception and several makers stating no warranty at all on their own pages.

The products this guide is about

Our verdict on each, with the full reasoning on the companion review.

What actually matters

  • Arbor thread size - the single spec that decides whether your saw and your arbor will meet. The market runs on 1/2 in. x 20 for saws up to 1-3/16 in. and 5/8 in. x 18 from 1-1/4 in. up, and Milwaukee, LENOX and Diablo all publish those same two numbers.
  • Quick-change system - the layer bolted on top of the thread, and the only place real lock-in happens. Milwaukee's QUIK-LOK and LENOX's SNAP-BACK are described as accepting threaded hole saws generally, while Diablo lists its own cups' shank as Diablo Mandrel.
  • Cutting edge material - bi-metal, carbide-tipped, carbide grit and diamond are rated for different work rather than being good, better and best. LENOX's published selection guide puts carbide-tipped top for stainless and cast iron and diamond top for tile and granite.
  • Depth of cut - the published figure for how thick a material the cup will pass in one go. A standard bi-metal saw is around 1-5/8 in., a deep-cut bi-metal around 2 in., and Diablo's carbide cups are published at 60 mm (2-3/8 in.).
  • Tooth pitch - how many teeth sit in an inch of cutting edge, and whether the spacing is constant or variable. Milwaukee's bi-metal HOLE DOZER is 3.5 TPI constant, Starrett's Fast Cut is 5.5 TPI constant, and Starrett's Deep Cut uses a variable pitch instead.
  • Plug ejection - how the disc of waste comes out of the cup, which you will do on every hole. Slots need a screwdriver, mandrel-based ejection is tool-free, and thin wall saws often include a spring that does it automatically.
  • Pilot bit length - the drill in the middle has to reach the work before the teeth do, and stay ahead of them. Milwaukee ships a 1/4 in. by 4 in. pilot with its arbor set, and LENOX sells pilot drills at 3-7/16 in. and 4-1/4 in. for its deeper cups.

The specs, in plain English

Arbor (or mandrel)The shaft that holds the hole saw and goes into the drill chuck. It carries the pilot drill in its centre and usually a pair of drive pins that stop the cup unscrewing under load. It is a separate purchase from the saw unless the kit includes one.
1/2 in. x 20 and 5/8 in. x 18The two thread sizes the industry runs on. The smaller one is used on hole saws from about 9/16 in. up to 1-3/16 in.; the larger takes over at 1-1/4 in. and runs to 6 in. and beyond. Adapters and adaptor nuts exist to bridge between them and onto quick-change systems.
Bi-metalA high speed steel cutting edge welded to a tougher steel body, which is the standard general purpose construction. It handles wood, plastics, drywall and most metals. Milwaukee lists the material composition of its HOLE DOZER saws as high speed steel and the application as wood and metal.
Carbide-tippedIndividual carbide teeth brazed or welded onto the cup, which stay sharp far longer in abrasive and hard material. Diablo rates its carbide cups for clean wood, nail-embedded wood, plastic, aluminium, metal, cast iron and stainless steel. They cost more and run at different speeds to bi-metal.
Carbide gritNo teeth at all, just a rim coated in tungsten carbide particles. LENOX describes it as designed for abrasive materials such as fibreglass, ceramic tile and laminates, and lists recommended speeds around 100 to 200 RPM. It is not a faster version of a toothed saw.
DiamondA continuous rim with industrial diamond bonded to it, for tile, stone and glass. LENOX lists suggested speeds for its diamond hole saws, for example around 800 to 1200 RPM at 7/8 in. dropping to 200 to 600 RPM at 2-1/2 in. Milwaukee's equivalent range is aimed at tile, stone and glass too.
TPI and variable pitchTeeth per inch. Fewer, larger teeth clear chips better in thick or soft material; more, finer teeth stay engaged in thin sheet without snagging. Variable or progressive pitch mixes the spacing along the edge, which Starrett uses on its Deep Cut range to cut with less vibration and noise.
Depth of cutThe published thickness the saw will pass through in one pass, which is less than the outside height of the cup. Standard bi-metal saws sit around 1-5/8 in., deep-cut versions around 2 in., and Diablo publishes 60 mm (2-3/8 in.) for carbide.
Plug (or slug)The disc of waste left inside the cup after the cut. Getting it out is the real-world annoyance of hole sawing, which is why makers publish slot designs, mandrel ejection and springs as named features rather than afterthoughts.

Green flags vs red flags

Green flags

  • The listing states a depth of cut in inches or millimetres rather than just a diameter.
  • The kit includes arbors or adapters for both the 1/2 in. x 20 and 5/8 in. x 18 thread ranges.
  • The maker publishes a recommended RPM by diameter and material, not just a single speed.
  • The tooth pitch is stated, and ideally whether it is constant or variable.
  • Plug removal is described as a specific mechanism, such as slots low on the cup, mandrel ejection or a spring.

Red flags

  • A quick-change system whose page only claims compatibility with the same brand's own saws.
  • A kit with a single arbor and saws that span both thread ranges.
  • No depth of cut anywhere in the listing, only diameters and a piece count.
  • Life claims given as a multiplier with no stated test material or comparison.
  • A saw sold with an integral hex shank and no thread, which cannot join any arbor system later.

Who's who: the brands

  • Milwaukee - Publishes the most per-size data in the category, including depth of cut and RPM by material, and backs HOLE DOZER with a limited lifetime tooth break warranty.
  • LENOX - The long-running bi-metal name, whose catalogue carries the fullest public speed charts, though several of its kit pages state no warranty applies.
  • Diablo - Carbide-focused, with the deepest published cut of the sets here and a Snap-Lock mandrel system that its own cups are built around.
  • Starrett - Splits its bi-metal range into a constant-pitch Fast Cut at 1-5/8 in. depth and a variable-pitch Deep Cut at 2 in., and states the material thickness each is for.
  • Bosch - Sells hole saws around its keyless Power Change Plus arbor, with screw-in adapters offered to fit other brands' saws to the system.

How to read a listing without getting fooled

Start at the bottom of the listing, not the top. Find the diameter, then look for a depth of cut; if the seller gives you one without the other, the listing is incomplete and you should go to the manufacturer's own page for the number. Next find the thread or the arbor reference, because that tells you whether this cup joins what you already own. Then read the cutting edge description literally: multi-material, carbide grit and carbide-tipped are three different things sold under overlapping words, and the maker's selection guide will tell you which one it puts top for your material. Finally check whether the maker publishes a recommended speed at all. A brand that will not tell you how fast to run a 4 in. saw in stainless is a brand that has left the most important variable to you.

How much should you spend?

Budget kits buy you saws and a conventional arbor, which is genuinely enough if you drill a few holes a month; the compromise is usually that the maker publishes less about them and offers no warranty. Mid-range is where you start getting a quick-change arbor with adapters for both thread ranges, published per-size data and a case that survives a van. Premium buys carbide teeth, a deeper cup and tool-free plug ejection, and it is worth it when you are cutting nail-embedded wood, cast iron or stainless regularly rather than occasionally. Spend the extra on the arbor before you spend it on the saws, because the arbor is the part you keep.

Questions, answered

Do I need a different arbor for large and small hole saws?

Usually yes. The industry uses 1/2 in. x 20 threads on saws from roughly 9/16 in. to 1-3/16 in. and 5/8 in. x 18 on saws from 1-1/4 in. upwards, and LENOX for instance lists separate arbor references for each range. Some quick-change systems get around this with adapters: Milwaukee's QUIK-LOK arbor set ships a small thread adapter, a large thread adapter and a large thread pin adapter on one shank. If your kit contains only one arbor, check which range it covers before you assume it covers both.

Is carbide always better than bi-metal?

No, it is different rather than strictly better. LENOX's own published selection guide rates carbide-tipped at the top for stainless steel and cast iron and multi-material carbide at the top for nail-embedded wood and masonry, while listing bi-metal as the good general option across ordinary wood and metal. Carbide also runs at different speeds: LENOX's carbide-tipped chart lists 1000 RPM for a 1-1/4 in. saw in aluminium where its bi-metal chart lists 410. For occasional holes in clean wood and mild steel, bi-metal is the sensible buy.

Why do big hole saws burn out so fast?

Almost always speed. Cutting speed at the rim rises with diameter, so the same drill setting that is fine on a 3/4 in. saw is far too fast on a 4 in. one. LENOX's published bi-metal chart drops from 460 RPM at 3/4 in. in mild steel to 85 RPM at 4 in., and to 40 RPM at 4 in. in stainless. Use the drill's low gear, keep steady pressure rather than heavy pressure, and back out often to clear chips.

Can I use a hole saw in an impact driver?

Only the ones sold for it, and they are a narrower tool than they look. Milwaukee's SHOCKWAVE thin wall hole saws use a 1/4 in. quick change hex shank and are rated for plastics and thin gauge metals up to 1/8 in. thick, with sizes stopping at 1-1/2 in. A conventional threaded hole saw on a standard arbor wants a drill with a chuck, low gear and preferably a side handle, because a large saw that binds will try to twist the tool out of your hands.

Ready to choose? See our top pick, the alternatives, and the one we'd skip See the Hole Saws verdicts

Related guides

Home NAS Devices After reading this you will understand what a home NAS does, which specs actually matter for your use, and how to read a spec sheet without being misled. Home Theater Projectors After reading this, you'll be able to look at any home theater projector listing and know which numbers matter, which are marketing, and what your room actually needs. Infrared Thermometers After reading, you'll understand why two guns with the same headline accuracy can disagree by tens of degrees, and which spec lines predict which one is telling the truth. Instant Cameras After reading this you'll know the difference between real film, Zink, and hybrid cameras - and which one fits how you actually shoot. Insulated Hand Tools After reading, you'll understand what the double triangle and 1000 V marks mean, why tools are proof tested at ten times their rating, what OSHA actually requires, and exactly what retires a tool. Internal NVMe SSDs After reading this you'll know which SSD specs actually make a system feel fast, which ones are marketing noise, and how to match a drive to your PC, laptop, or PS5.