Annular cutters drill clean, accurate holes in steel plate up to 8 times faster than a twist drill and with a fraction of the force. They are the standard cutter for magnetic drills used by structural fabricators, scaffolders, formworkers and mining maintenance crews. But the buyer-side questions never stop: which shank fits my mag drill, do I need HSS or TCT, why does the slug keep getting stuck, what depth of cut do I need, and can I use one in a drill press? This guide answers all of them, grounded in the 3/4 inch Weldon shank universal standard, manufacturer specifications, and 25+ forum-validated insights from Practical Machinist, Hobby-Machinist, Garage Journal, WeldingWeb, metalworkforums.com and the wider AU and US machinist communities.
AIMS Industrial stocks 32+ annular cutter products across Bordo (Australian-made, broadest range), Sutton Tools (AU patriot, premium TiAlN coating), Euroboor (European Weldon specialist), Alpha (impact-rated value), and Maxbor (pilot pin replacement specialist). See the Annular Cutters & Sets collection for the complete range.
What is an annular cutter and how does it work?
An annular cutter is a hollow cylindrical cutting tool with teeth around the outer edge that cuts only the circumference of a hole, leaving a solid plug (the "slug") at the centre. Unlike a twist drill that converts the entire hole volume into chips, an annular cutter removes only an annular ring of material around the circumference. This is the source of its speed advantage and clean cut quality.
Annular cutters are also called broach cutters, Slugger cutters (after Jancy/Fein Slugger, the brand that established the generic term), mag drill bits, core drill bits and Rotabroach cutters. All refer to the same product class.
The slug is automatically ejected at the end of the cut by a spring-loaded pilot pin (also called the centring pin or ejection pin) running down the cutter's hollow centre. As the cutter breaks through the workpiece, the spring pushes the slug out the top of the cutter, leaving the cutter immediately ready for the next hole.
The combination of cutting only around the rim plus automatic slug ejection makes annular cutters the standard tool for high-volume hole-making in steel plate. Practitioner consensus from Practical Machinist, Hobby-Machinist and metalworkforums.com: "annular cutters take much less force and drill a very clean hole" and "are bar none, one of the fastest mechanical ways to machine an accurate hole in a piece of metal."
The 3/4 inch Weldon shank — the universal industrial standard
The 3/4 inch Weldon shank (19.05mm) is the universal standard for annular cutter mounting in magnetic drills. Every major mag drill manufacturer worldwide — Hougen, Milwaukee, Alfra, BDS, Ruko, Euroboor, Jancy/Fein, Bosch, Holemaker, Bordo, Excision — builds machines that accept 3/4 inch Weldon shank cutters.
The Weldon shank consists of a cylindrical 3/4 inch diameter stem with two flat-machined faces at 180° opposing each other near the top. The mag drill's quick-change chuck has set screws that engage these flats, locking the cutter against rotation under high torque while still allowing one-handed removal when the set screw is released. This solves two problems at once: torque transmission without slip, and tool change without specialised tooling.
| Shank Standard | Diameter | Use | Compatibility |
|---|---|---|---|
| 3/4 inch Weldon | 19.05mm | Universal mag drill standard | Hougen, Milwaukee, Alfra, BDS, Ruko, Euroboor, Jancy, Holemaker, Bordo, Excision |
| 1-1/4 inch Weldon | 31.75mm | Heavy industrial / large-diameter cutters | Larger mag drills with heavy-duty chucks |
| 3/4 inch Universal Weldon | 19.05mm | Same dimensional standard as Weldon — different brand label | Marketing term — physically interchangeable with 3/4 inch Weldon |
| Nitto One-Touch (quick-change) | ~19mm | Quick-change collet — Hougen/Nitto-style | Requires adapter to mount standard Weldon cutters |
| MT2 / MT3 with Weldon adapter | Morse Taper 2/3 | Drill press use of Weldon shank cutters | Adapter required — see drill press section |
| Proprietary (Vevor quick-change) | Specially machined Weldon-end | Vendor-specific — buyer trap | Replacement cutters very hard to source — forum-flagged warning |
The "Universal" terminology trap: "Universal shank" and "Weldon shank" are functionally the same thing at 3/4 inch (19.05mm). Marketers use "Universal" to indicate cross-brand compatibility, but the physical dimensions match the Weldon standard. The exception is the Nitto One-Touch quick-change system, which uses a different collet engagement — adapters are required to mount Weldon cutters in a Nitto-style chuck.
AIMS stocks the Euroboor Nitto One-Touch to 3/4" Weldon adapter for converting Nitto-style chucks to accept standard Weldon cutters.
Forum-flagged buyer warning: Cheap import mag drills (Vevor, Steel Dragon) sometimes use a "quick-change nose" that requires specially machined Weldon shank ends. Replacement cutters become very hard to source because standard Weldon cutters do not fit. Direct quote from a Practical Machinist user: "Replacement cutters very hard to source." Verify your mag drill accepts standard 3/4 inch Weldon before buying a budget machine.
Pilot pin function — the slug ejection mechanism
The pilot pin is the most-misunderstood part of an annular cutter. Buyers ask why it's there, why brand A's pin doesn't fit brand B's cutter, and why their slug keeps jamming in the cutter. The answer to all three is the same: the pilot pin does two distinct jobs.
Job 1 — Centring the cut
At the start of the cut, the pilot pin extends about 3-5mm beyond the cutter teeth. The operator positions the pilot pin against the workpiece surface (or in a centre-punched mark) to locate the hole. As feed pressure is applied, the pilot pin retracts into the cutter against the internal spring, allowing the cutter teeth to engage the workpiece at the correct centre.
Job 2 — Ejecting the slug
This is the critical function. As the cutter breaks through the bottom of the workpiece, the trapped slug remains inside the cutter body. The pilot pin, powered by its internal spring, immediately pushes the slug out through the top of the cutter. The slug pops free, and the cutter is ready for the next hole.
Without a functioning pilot pin, the slug stays inside the cutter. Next cut, the cutter tries to enter the workpiece with the previous slug still trapped — and cutter shatter or workpiece spoilage is the result. The pilot pin is not optional. It is the ejection mechanism.
Why brand pilot pins are not interchangeable. Each manufacturer machines the pilot pin pocket, spring force and pin diameter to their own specification. Sutton, Bordo, Euroboor, Hougen and Holemaker all use proprietary pilot pin geometries. The internal spring length, pin shank diameter, and ejection travel are not standardised across brands. Stick with one brand for cutter and pilot pin matching. Forum direct quote: "Different brands of annular cutters have different and not interchangeable pilots."
AIMS stocks dedicated pilot pin replacements:
- Sutton 25mm cutter pilot pin
- Sutton 50mm cutter pilot pin
- Sutton 75mm cutter pilot pin (7.98 x 130mm)
- Bordo 1/4 inch pin + Bordo 8mm pin
- Bordo 8mm pin for 25mm TCT rail cutter
- Bordo 8mm pin for 50mm TCT annular cutter
- Euroboor ejection pilot pin
- Maxbor 77mm ejection pilot pin
- Maxbor 82mm reduced shank pin
- Maxbor 102mm ejection pilot pin
- Maxbor 102mm reduced shank pin
- Maxbor 112mm pin (suits TCHSS 14-17mm cutter)
The #1 forum-validated mistake — pre-drilled centre hole. Do NOT pre-drill a centre hole before using an annular cutter. The pilot pin needs a solid centre to push the slug out. A pre-drilled centre hole means there is no slug bottom for the pilot pin to push against, so the slug jams in the cutter body. Practical Machinist direct quote: "Do not drill a center hole unless you want a stuck slug."
HSS vs TCT — the material decision
Annular cutters come in two main tooth materials: High Speed Steel (HSS) and Tungsten Carbide Tipped (TCT). The choice depends on the workpiece material, expected hole count, and whether you want the option to re-sharpen.
| Property | HSS | TCT (Tungsten Carbide Tipped) |
|---|---|---|
| Best for | Mild steel, aluminium, brass, copper | Hardened steel, stainless, Bisalloy, wear plate, exotic alloys |
| Cutting speed | Lower — longer time per hole | Higher — faster cycle time, suits production work |
| Initial cost | Lower | 2 to 4 times the HSS price for same diameter |
| Re-sharpenable | Yes — 3 to 5 regrinds typical, extends tool life significantly | No — consumed and replaced once dull |
| Speed sensitivity | Damaged by exceeding recommended RPM by more than 20% | Damaged by running too slow — needs minimum speed to avoid vibration and tooth chipping |
| Lubricant | Cutting oil (straight or mineral oil) | Water-based emulsion coolant |
| Versatility | General workshop, mild steel default | Stainless, hardened, high-volume production |
| Coating options | Black oxide (entry), TiN, TiAlN (premium) | Bare carbide tips (no coating needed) |
The TCT low-speed trap. Forum-validated insight from manufacturer technical literature and Hobby-Machinist threads: "TCT annular cutters are more sensitive to excessively low speed, which leads to increased vibration and teeth damage." Running TCT too slow chips the carbide teeth and destroys the cutter. If your mag drill cannot reach the minimum recommended RPM for a TCT cutter at a given diameter, use HSS instead.
The HSS over-speed trap. The opposite problem with HSS: "HSS annular cutters are more sensitive when recommended values are exceeded by more than 20%." Running HSS too fast burns the teeth and destroys the cutter. The 20% rule is the practitioner's working margin.
HSS coatings explained. Black oxide is the entry-level finish — adequate for general mild steel. TiN (titanium nitride, gold) extends tool life 2-3x on mild steel. TiAlN (titanium aluminium nitride, dark grey/violet) is the premium coating — tolerates higher temperatures, suits stainless work and heat-resistant alloys. The Sutton H182 M2Al HSS TiAlN annular cutter uses the M2Al (M2 high-speed steel with aluminium) substrate plus TiAlN coating — the premium HSS specification for AU workshops.
Depth-of-cut sizing — 25mm to 110mm by application
Annular cutters are specified by both diameter and depth of cut. Depth of cut is the maximum workpiece thickness the cutter can drill through in a single pass — and it determines which cutter you need for which job. Buying a 25mm-depth cutter and trying to drill a 50mm plate means the cutter teeth bottom out in the workpiece before breaking through.
| Depth of cut | Standard applications | AU industrial use cases |
|---|---|---|
| 25mm (1 inch) | Light fabrication, sheet metal up to 20mm | Workshop general purpose, light structural plate, rail flange holes |
| 30mm | Slightly thicker general fabrication | Structural plate, heavy gauge sheet, formwork |
| 50mm (2 inch) | Most general fabrication and structural work | Workshop default for structural fabrication, beam connections, base plates |
| 55mm | Slightly deeper than 50mm — common European spec | Heavy structural, common with Euroboor Weldon cutters |
| 75mm (3 inch) | Heavy structural, deep base plates | Tower crane base plates, mining maintenance, heavy formwork |
| 110mm (4.3 inch) | Very heavy structural, mining infrastructure | Mining shovel maintenance, ship repair, bridge construction |
Workshop standard depth. The most-used depth across AU fabrication shops is 50mm. It handles the vast majority of structural steel plate work (up to 40mm thick comfortably) without paying for unused depth capacity. AIMS stocks 50mm cutters across multiple brands — see Bordo 50mm HSS-M2Al, Bordo 50mm TCT, Alpha 50mm Carbide Xtra TCT and the Sutton H182 M2Al TiAlN range.
Forum-validated buying tactic. Garage Journal practitioner direct quote: "2-inch depth of cut preferred — costs more than 1-inch but the extra depth is useful." The workshop logic is simple: a 50mm-depth cutter can drill any plate up to 40mm thick, while a 25mm-depth cutter only handles plate up to about 20mm. The cost difference is rarely justifiable as a saving when you consider the workflow disruption of finding out mid-job that the cutter is too shallow.
Diameter and size ranges — 12mm to 100mm coverage
Annular cutters are available from approximately 12mm diameter up to 100mm+. AIMS-stocked sizes from the Bordo HSS-M2Al range demonstrate the practical workshop coverage:
- 25mm — small fabrication holes, bracket fixings, light structural (Bordo 25mm HSS) (Bordo 25mm TCT Rail)
- 50mm — workshop standard, base plate holes, structural connections (Bordo 50mm HSS) (Bordo 50mm TCT)
- 75mm — heavy structural, large bolt holes (Bordo 75mm TCT)
- 100mm — very heavy structural, foundation bolts (Bordo 100mm HSS) (Bordo 100mm TCT)
Smaller intermediate sizes (16, 18, 20, 22, 30, 32, 35, 40, 55, 60mm) are available across the Euroboor and Sutton ranges. For broader size coverage in HSS, the Euroboor Long Series 8-piece annular cutter set covers the most-used workshop sizes in a single carded set — a strong starter pack for fabrication shops without an existing inventory.
Forum-validated cost-spread tactic. Reddit/Garage Journal practitioner advice: "Buy a full set of smaller rotabroaches and order singles for frequently used annular cutter sizes." The full set covers most one-off jobs at minimum total cost; singles in your high-use sizes (50mm being the most common in AU fab shops) cover the wear replacements as needed. Spreads the cost over time without leaving gaps in size coverage.
Annular cutter vs hole saw vs twist drill — the decision matrix
Annular cutters are not the right choice for every hole. They live in a specific niche: large-diameter (typically 12mm+), accurate, clean-cut holes in steel plate. Outside that niche, hole saws or twist drills are better.
| Tool | Best for | Materials | Hole quality | Speed vs twist drill |
|---|---|---|---|---|
| Twist drill | Holes under 25mm, all general drilling | Steel, aluminium, wood, plastic — any material | Decent for diameter, can wander in steel without pilot | Baseline (1x) |
| Step drill | Thin sheet metal, multiple sizes from one tool | Sheet metal, thin plate, soft metals | Clean entry, can ream slightly | Faster on sheet, slower on thick plate |
| Hole saw (bi-metal) | Large-diameter holes 20mm+ in thin material | Wood, plastic, thin sheet, light gauge steel | Rough cut, requires deburring | Slow on thick steel — wrong tool |
| Hole saw (TCT) | Large-diameter holes in harder materials | Stainless, hardened steel, fibreglass, masonry | Cleaner than bi-metal, still requires deburring | 2-3x faster than bi-metal on hard materials |
| Annular cutter | Large-diameter (12mm+) accurate clean holes in steel plate | Steel, stainless, hardened plate — needs mag drill or drill press | Reamer-quality finish, no deburring needed | 3-8x faster than twist drill |
The annular cutter advantage zone. Multiple forum threads (Practical Machinist, Hobby-Machinist, WeldingWeb) converge on the same rule: annular cutters become the right choice when the hole diameter exceeds 12mm AND the workpiece is steel plate AND there is more than one hole to drill. Below 12mm, twist drills are faster to set up. In wood/plastic/thin sheet, hole saws win on tool cost. For a single hole below 25mm in steel, a step drill or twist drill wins on setup time.
For deep-dive coverage of the magnetic drill machine itself, see our Magnetic Drill Guide.
Speed and feed — RPM by diameter and material
Annular cutter RPM is set by cutter diameter and workpiece material. Run too fast and HSS cutters burn; run too slow and TCT cutters chip. The table below consolidates manufacturer data and forum-validated practitioner figures for mild steel, stainless, and aluminium.
| Cutter diameter | Mild steel (HSS) | Mild steel (TCT) | Stainless (TCT mandatory) | Aluminium (HSS) |
|---|---|---|---|---|
| 12mm | 700-900 RPM | 500-700 RPM | 400-550 RPM | 1200-1500 RPM |
| 20mm | 500-650 RPM | 450-550 RPM | 350-450 RPM | 900-1100 RPM |
| 25mm | 450-550 RPM | 400-500 RPM | 300-400 RPM | 700-900 RPM |
| 30mm | 400-500 RPM | 350-450 RPM | 275-375 RPM | 600-800 RPM |
| 40mm | 300-400 RPM | 275-375 RPM | 225-300 RPM | 450-600 RPM |
| 50mm | 250-350 RPM | 225-325 RPM | 200-275 RPM | 375-500 RPM |
| 75mm | 175-250 RPM | 150-225 RPM | 125-175 RPM | 250-350 RPM |
| 100mm | 125-200 RPM | 100-175 RPM | 100-150 RPM | 175-275 RPM |
The "do not peck" rule. Hobby-Machinist practitioner direct quote: "Use constant pressure for continuous cutting — do not peck at the work." Once the cutter is engaged, maintain steady feed pressure until the slug ejects. Pecking (lifting the cutter mid-cut and re-engaging) creates a step in the hole, jams chips against the cutter teeth, and can shatter the cutter on re-entry.
Stainless work-hardening trap. Stainless steel work-hardens rapidly when the cutter dwells without removing material. If you pause feed pressure on stainless — even for a few seconds — the work surface hardens and the cutter teeth fail within the next pass. Forum direct rule: once you start a stainless cut, do not stop until the slug ejects.
Deep-hole feed protocol. For holes deeper than 30mm: every 20-30mm of depth, retract the cutter, clear chips, lubricate, and continue with lower feed pressure. Chips packed against the cutter teeth cause overheating and premature failure.
For broader cutting speed and feed reference across all machining operations, see our Cutting Speeds and Feeds Chart.
Cutting fluid — required types and the never-do list
Annular cutters always require cutting fluid. Running dry destroys the cutter in minutes and risks workpiece damage from heat. The lubricant type depends on the cutter material and the work orientation.
HSS cutters — cutting oil
HSS annular cutters use straight cutting oil (mineral oil with extreme-pressure additives). Mag drills typically have a drip-feed bottle of cutting oil mounted on the column, with internal delivery through the pilot pin centre to the cutting zone. Slow drip is sufficient — flood coolant is not required.
TCT cutters — water-based emulsion
TCT annular cutters use water-based emulsion coolant at typical concentrations (5-10% emulsion in water). The water carries heat away from the carbide teeth faster than oil, which suits the higher cutting speeds TCT can run.
Overhead and vertical work — paste and stick lubricants
For overhead drilling, vertical surfaces, and outdoor work where liquid lubricants drip and create motor short-circuit hazards, use cutting paste or wax-formula stick lubricants ("slick sticks"). These cling to the cutter without dripping and provide sufficient lubrication for moderate-duty work. BDS Machines technical guidance: liquid lubricants should not be used overhead due to motor risk; cutting paste or wax sticks are the standard alternative.
The never-do list — what NOT to use as annular cutter lubricant:
• Water alone — flash rusts the cutter and workpiece, no lubricant film
• Car windscreen washer fluid — solvent-based, attacks elastomer seals in the mag drill
• WD-40 — penetrant, not a cutting lubricant — burns off instantly under cutter heat
• Engine oil — viscosity too high, traps chips, prevents heat dissipation
• Brake fluid — chemical hazard, damages workpiece and cutter coating
BDS Machines direct guidance: "never use water, car-window clearing liquid, solvents or other liquids as a cutting lubricant, as it will not only lead to damage of the annular cutter, but also all other equipment."
For workshop cutting fluid selection across all operations, see our Cutting Fluids Guide.
Annular cutters in a drill press — with the right adapter
Annular cutters are designed for magnetic drills, but they CAN be used in a standard drill press or milling machine with the correct adapter. The adapter converts the drill press spindle (Morse Taper) to a 3/4 inch Weldon shank receiver, allowing the annular cutter to mount.
The rigidity requirement. Drill presses are less rigid than mag drills, and the workpiece must be securely clamped. Practical Machinist consensus: annular cutters work in drill presses for occasional use, but for production work the mag drill is the correct tool. Larger cutters (above 30mm) demand more rigidity than most bench drill presses can supply.
Adapter quality matters. Forum direct quote: "Some of the cheap adapters don't allow the ejector to work right." A proper adapter has internal clearance and spring for the pilot pin to function — slug ejection still works. Cheap adapters block the pilot pin and turn every cut into a slug-removal project.
AIMS stocks the Bordo MTS Adaptor for Annular Cutter (Morse Taper to Weldon) and the Euroboor MT2-to-Weldon Arbor with Lube Ring — both designed to preserve pilot pin ejection and (for the Euroboor) internal lubrication delivery.
Adapter options — MT2, MT3, Nitto and hand drill
The annular cutter's universal Weldon shank means that with the right adapter you can mount it in almost any drilling tool. The most common conversions:
- Morse Taper 2 (MT2) to 3/4 inch Weldon — fits MT2 drill presses. Single most common drill press adapter. Euroboor MT2 to Weldon with Lube Ring
- Morse Taper 3 (MT3) to 3/4 inch Weldon — fits MT3 drill presses, common on larger bench and pedestal machines. Available through specialty supplier network — contact AIMS.
- Nitto One-Touch to 3/4 inch Weldon — converts Nitto-style quick-change chucks (Hougen and similar mag drills) to accept standard Weldon cutters. Euroboor Nitto adapter
- Drill chuck (Jacobs taper) to 3/4 inch Weldon — allows annular cutter use in a hand drill or any chuck-equipped tool. Practical for emergency use or very light-duty work — not recommended for production. Specialty source on request.
For deeper coverage of Morse Taper standards, see our Morse Taper Guide. For drill chuck reference, see our Drill Chuck Guide.
For full-time use of Weldon shank tools in a standard drill press (other than annular cutters), the Euroboor Weldon Shank Twist Drill HSS uses the same shank standard — useful for jobs that need both annular cutters and twist drills in the same setup without a chuck change.
Common failure modes — and how to prevent them
Annular cutters fail in predictable ways. Each failure mode has a known cause and a known prevention. The table below consolidates forum-validated failure causes from Practical Machinist, Hobby-Machinist, Garage Journal, WeldingWeb and metalworkforums.com.
| Failure mode | Cause | Prevention |
|---|---|---|
| Slug stuck in cutter | Pre-drilled centre hole, broken pilot pin, dull cutter, wrong brand pilot | Never pre-drill centre; replace pilot pin if spring weak; resharpen or replace cutter |
| Cutter wanders off centre | Pilot pin too short, worn pilot pin, no pilot pin | Replace pilot pin with matching brand spec |
| Tooth chipping (TCT) | RPM too low, feed too aggressive, interrupted cut | Increase RPM to recommended range; maintain steady feed; never peck |
| Tooth burning (HSS) | RPM too high, no lubricant, dry cut | Reduce RPM to recommended range; ensure continuous lubricant flow |
| Cutter shatter on re-entry | Previous slug not ejected; chips packed in cut | Inspect cutter empty before next hole; clear chips on deep cuts |
| Pilot pin snapped | Sideways force, dropped tool, fatigue from repeated impact | Avoid lateral force during cut; replace pilot at first sign of bend |
| Premature tooth wear (stainless) | Feed paused mid-cut → work-hardening | Maintain continuous feed once engaged; never dwell |
| Cutter binds in hole | Workpiece shift mid-cut, insufficient mag drill grip | Workpiece thickness ≥1/2" for reliable magnet grip; clamp thin material |
| Workpiece slips on mag drill | Plate too thin for full magnet hold | Below 12mm plate, secondary clamping mandatory |
| Pilot pin won't retract | Bent pilot, debris in pin pocket, broken spring | Clean pin pocket regularly; replace bent pin immediately |
Mag drill plummet hazard — AU work safe notifiable. Direct report from metalworkforums.com AU practitioner: a mag drill "plummeted 60-odd metres to the ground and became a work safe notifiable" after the magnet failed during vertical/overhead use. Risk factors: thin workpiece (under 12mm), paint or dirt on the magnet contact surface, reverse polarity from a battery-backed unit, sudden workpiece shift, or cutter binding. Always use the safety chain for vertical and overhead mag drill work. Verify magnet contact surface is clean bare steel. Workpiece thickness below 12mm requires secondary clamping. Don't trust the magnet alone for fall protection.
HSS re-sharpening economics — when to scrap, when to regrind
One real cost advantage of HSS over TCT: HSS annular cutters can be re-sharpened, typically 3-5 times across their service life. TCT cutters cannot be re-sharpened — the carbide tips chip rather than wear, and once the geometry is lost they're scrap.
Re-sharpening service cost in AU is typically a fraction of replacement cost — making HSS the lower total-cost-of-ownership option for shops doing repeat work in mild steel. The decision rule:
- HSS cutter showing first dullness signs (slower cut, more force needed): regrind. Three to five regrinds expected.
- HSS cutter with chipped or broken teeth: scrap. The tooth geometry cannot be recovered.
- HSS cutter with cracked body: scrap immediately — safety risk.
- TCT cutter showing dullness or tip chipping: scrap. No re-sharpening available.
Cutting Tools Chicago and other specialist sharpening services note that HSS annular cutter re-sharpening uses a plated grinding wheel to dress both the external flank and the gullet in a single setup. The geometry is achievable on standard tool grinders but requires the correct fixture — most shops outsource to a sharpening specialist rather than DIY.
AU brand reality — Bordo, Sutton, Euroboor at AIMS plus honest scope
AIMS Industrial stocks 32+ annular cutter products across five brands. The supply ladder maps to workshop tier:
| Brand | Country | AIMS range | Positioning | Tier |
|---|---|---|---|---|
| Bordo | Australia (Castle Hill NSW) | 12 SKUs — HSS-M2Al, TCT, rail cutters, pilot pins, MTS adapter | Broadest AIMS range, AU-made workshop tier | Workshop value |
| Sutton Tools | Australia (Thomastown VIC) | 4 SKUs — H182 M2Al HSS TiAlN + 3 pilot pins | AU patriot premium, TiAlN-coated | Premium AU |
| Euroboor | Netherlands (European) | 9 SKUs — 30/35/55mm Weldon HSS + TCT, 8-piece set, MT2 arbor, Nitto adapter | European Weldon specialist, deepest adapter range | Premium European |
| Alpha | USA (impact-rated specialist) | 1 SKU — 50mm Carbide Xtra TCT | Impact-rated TCT alternative at workshop pricing | Value TCT |
| Maxbor | Australia | 5 SKUs — 77/82/102/112mm pilot pins | Pilot pin replacement specialist | Spares |
Bordo (Australian, broadest AIMS range)
Bordo is Castle Hill NSW-based and the deepest annular cutter range at AIMS. 12 SKUs covering HSS-M2Al and TCT in 25mm, 50mm, 75mm and 100mm diameters, plus 25mm TCT rail cutter, pilot pins (8mm and 1/4"), and the MTS drill press adapter.
- Bordo 25mm HSS-M2Al
- Bordo 50mm HSS-M2Al
- Bordo 100mm HSS-M2Al
- Bordo 50mm TCT
- Bordo 75mm TCT
- Bordo 100mm TCT
- Bordo 25mm TCT Rail Cutter (specialty for rail flange work)
- Bordo MTS Adaptor for Annular Cutter
Sutton Tools (AU patriot, premium TiAlN)
Sutton Tools is Thomastown VIC-based and Australia's largest cutting tool manufacturer. The annular cutter offering at AIMS is focused — a single premium-coated cutter range plus dedicated pilot pins for the workshop-standard sizes. The featured product:
- Sutton H182 M2Al HSS TiAlN Annular Cutter — the AU patriot premium pick. M2Al substrate (M2 high-speed steel with aluminium) plus TiAlN coating. The coating handles higher cutting temperatures and extends tool life on stainless and harder steels. Multiple sizes available within the H182 range.
- Sutton 25mm cutter pilot pin
- Sutton 50mm cutter pilot pin
- Sutton 75mm cutter pilot pin (7.98 x 130mm)
Sutton positioning: when you want AU-manufactured premium HSS with TiAlN coating for harder workpiece materials, the H182 is the AIMS pick. The Sutton pilot pin range covers the workshop-standard 25/50/75mm sizes for replacement consumables.
Euroboor (European Weldon specialist)
Euroboor is a Netherlands-based annular cutter specialist with a strong Weldon shank range and the most complete adapter offering at AIMS. 9 SKUs covering 30/35/55mm cutters in HSS Black Oxide and Weldon TCT, plus the 8-piece Long Series set, MT2-to-Weldon arbor with lube ring, Nitto adapter, ejection pilot pin, and Weldon shank twist drill.
- Euroboor 8-piece Long Series Annular Cutter Set — strong starter pack for new fabrication shops
- Euroboor 30mm Weldon HSS Black Oxide
- Euroboor 55mm Weldon HSS Black Oxide
- Euroboor 35mm Weldon TCT
- Euroboor 55mm Weldon TCT
- Euroboor MT2-to-Weldon Arbor with Lube Ring (drill press use with internal lubrication)
- Euroboor Nitto One-Touch to 3/4" Weldon Adapter
- Euroboor Ejection Pilot Pin
- Euroboor Weldon Shank Twist Drill HSS
Alpha (impact-rated value)
Alpha specialises in impact-rated cutting tools and offers a single TCT annular cutter:
- Alpha 50mm Carbide Xtra TCT Annular Cutter — alternative to Bordo 50mm TCT at competitive workshop pricing
Maxbor (pilot pin replacement specialist)
Maxbor focuses on pilot pin replacements for the workshop range — 5 SKUs covering 77mm/82mm/102mm/112mm standard and reduced-shank pilot pins:
- Maxbor 77mm pilot pin
- Maxbor 82mm reduced shank pilot pin (4.2-4.8mm)
- Maxbor 102mm pilot pin
- Maxbor 102mm reduced shank pilot pin (4.2-4.8mm)
- Maxbor 112mm pilot pin for TCHSS 14-17mm cutter
Honest scope — brands NOT stocked at AIMS
The AU annular cutter market also includes brands AIMS does not currently stock. We're upfront about that:
- Holemaker (AU) — Australia's most comprehensive annular cutter range with 750+ types. Dominant in the AU mag drill aftermarket. Not currently in AIMS supply — source on request through our supplier network.
- Hougen, Jancy/Fein Slugger, Champion, Milwaukee (US) — the US gold-standard brands. Hougen 12000 Series and CopperHeads are particularly well-regarded for structural steel work. Not stocked at AIMS — specialty source on request.
- HMT Carbidemax, Rotabroach Raptors (UK) — UK-favoured premium options. Not in AIMS supply.
- Excision (AU) — AU brand with annular cutter range. Not currently stocked at AIMS.
For these brands, we'll happily source through our supplier network — call AIMS on (02) 9773 0122 or use the contact form with the spec you need and we'll quote and lead time.
Annular cutter selection checklist
Before buying, run through this 8-point checklist:
- Shank standard: Does your mag drill or drill press accept 3/4 inch Weldon? Most do. If you have a Nitto quick-change or Vevor proprietary shank, identify the adapter needed.
- Workpiece thickness: Maximum plate you'll drill through? Pick a cutter with depth-of-cut at least 10% greater. Workshop default = 50mm depth.
- Diameter range: What hole sizes do you drill regularly? Buy your top 3-5 sizes individually; consider the Euroboor 8-piece set for one-off coverage.
- Workpiece material: Mild steel = HSS or TCT. Stainless or hardened steel = TCT mandatory. Aluminium = HSS.
- Production volume: Occasional use = HSS (re-sharpenable). High-volume production = TCT (faster cycle time).
- Pilot pin matching: Buy pilot pins of the same brand as your cutters. Not interchangeable across brands.
- Lubricant compatibility: HSS = cutting oil. TCT = water-based emulsion. Overhead = paste or stick.
- Mag drill compatibility: Verify your mag drill RPM range matches the speed table for your largest cutter diameter. TCT cutters need minimum speed; HSS cutters need maximum speed control.
Common mistakes — forum-validated
The most-frequent buyer and operator mistakes from 25+ machinist and welder forum threads:
- Pre-drilling a centre hole. The #1 cause of stuck slugs. Don't pre-drill. The pilot pin needs a solid centre to push.
- Mixing pilot pin brands. Bordo pilot pin doesn't fit a Sutton cutter. Stick with one brand for matched consumables.
- Pecking the cut. Lifting the cutter mid-cut breaks teeth and creates stepped holes. Steady continuous feed only.
- Running TCT too slow. Carbide teeth chip when vibration develops at low speed. Speed up, don't slow down.
- Running HSS too fast. 20% over recommended RPM burns the teeth. Stick to the speed table.
- Skipping cutting fluid. Dry cuts kill cutters in minutes. Always lubricate.
- Wrong lubricant. Water, window cleaner, WD-40, engine oil all damage cutters. Use cutting oil (HSS) or emulsion coolant (TCT).
- Pausing feed on stainless. Work-hardens the surface in seconds. Once engaged, finish the cut.
- Cheap drill press adapter. Blocks pilot pin ejection. Buy a quality adapter (Bordo MTS or Euroboor MT2-Weldon).
- Trusting magnet alone overhead. Mag drill plummet hazard is real. Use the safety chain. Verify magnet contact. Thickness ≥12mm for reliable hold.
Frequently Asked Questions
What is an annular cutter used for?
Annular cutters are used to drill clean, accurate large-diameter holes in steel plate up to 8 times faster than a twist drill. Standard applications: structural fabrication, base plate holes, bolt holes in beams, rail flange holes, mining maintenance, ship repair, formwork. They are designed primarily for magnetic drills but can be used in drill presses and milling machines with the correct adapter.
What size Weldon shank is standard for annular cutters?
The universal industrial standard is 3/4 inch (19.05mm) Weldon shank with two opposing flat faces. Every major mag drill brand worldwide (Hougen, Milwaukee, Alfra, BDS, Ruko, Euroboor, Jancy, Holemaker, Bordo, Excision) builds machines that accept 3/4 inch Weldon cutters. Larger heavy-industrial cutters use 1-1/4 inch (31.75mm) Weldon shank. The term "Universal shank" is marketing-speak for the same 3/4 inch Weldon dimension.
Why is my annular cutter slug getting stuck?
Three common causes: (1) you pre-drilled a centre hole — the pilot pin has nothing to push against, so the slug jams. Never pre-drill. (2) The pilot pin spring is weak or broken — replace with matching-brand pilot pin. (3) The cutter is dull — the slug deforms during cut and binds in the cutter body. Re-sharpen (HSS) or replace (TCT).
Are different brand pilot pins interchangeable?
No. Sutton, Bordo, Euroboor, Hougen, Holemaker and Maxbor all use proprietary pilot pin geometries. Pin shank diameter, length, spring force and ejection travel are not standardised. A Bordo pin in a Sutton cutter will either not fit or will fail to eject the slug properly. Stick with one brand for cutter and pilot pin matching.
Can I use an annular cutter in a drill press?
Yes, with the correct adapter. AIMS stocks the Bordo MTS Adaptor and the Euroboor MT2-to-Weldon Arbor with Lube Ring — both are designed for drill press use of standard 3/4 inch Weldon annular cutters. Drill press limitations: less rigid than a mag drill, larger cutters (above 30mm) demand more rigidity than most bench drill presses can supply, workpiece must be securely clamped. Cheap generic adapters can block pilot pin ejection — buy quality.
HSS vs TCT annular cutter — which should I buy?
HSS for mild steel, aluminium and general workshop use — lower cost, re-sharpenable 3-5 times, suits occasional and varied work. TCT for stainless, hardened steel, Bisalloy and high-volume production — higher cost, not re-sharpenable, faster cycle time, mandatory for stainless. If you're cutting mainly mild steel under 25mm depth at occasional volume, HSS wins on total cost. If you're cutting stainless or doing repetitive production runs, TCT wins on speed.
What RPM should I run an annular cutter at?
RPM is set by cutter diameter and material. General rule for mild steel HSS: 12mm = 700-900 RPM, 25mm = 450-550, 50mm = 250-350, 75mm = 175-250, 100mm = 125-200. Slower for larger diameters. TCT runs about 20% slower than HSS in the same material. Stainless runs 25-30% slower than mild steel. Aluminium runs about 1.5-2x faster than mild steel. See the speed and feed table above for full reference.
Do I need cutting fluid with an annular cutter?
Yes, always. Dry cuts destroy annular cutters in minutes. HSS cutters need straight cutting oil — mag drills typically have a drip-feed bottle delivering oil through the pilot pin centre. TCT cutters need water-based emulsion coolant (5-10% in water). For overhead and vertical work, use cutting paste or wax-formula stick lubricants to avoid drip hazards. Never use water alone, windscreen washer fluid, WD-40 or engine oil as cutting lubricant.
What depth of cut do I need?
The workshop default is 50mm (2 inch) depth of cut — handles plate up to about 40mm thick comfortably. For light fabrication or sheet work, 25mm depth is adequate. For heavy structural (tower crane base plates, mining shovel maintenance), 75mm or 110mm depth is needed. Pick a cutter with depth-of-cut at least 10% greater than your maximum workpiece thickness.
Can I sharpen an annular cutter?
HSS annular cutters can be re-sharpened — typically 3-5 regrinds across their service life. The geometry requires a plated grinding wheel and a fixture, so most shops outsource to a sharpening service rather than DIY. TCT (tungsten carbide tipped) annular cutters cannot be re-sharpened — the carbide tips chip rather than wear, and once geometry is lost they're scrap.
What's the difference between an annular cutter and a hole saw?
Both cut hollow rings, but they're designed for different jobs. Hole saws (bi-metal or TCT) suit thin material — wood, plastic, light gauge sheet metal — and produce rougher holes that often need deburring. Annular cutters suit steel plate from 6mm up to 110mm thick, produce reamer-quality holes, and are 3-8x faster than twist drills. Annular cutters require a mag drill or drill press with adapter; hole saws fit any standard drill chuck.
What is Holemaker and why is it not stocked at AIMS?
Holemaker is the dominant AU brand for annular cutters, with 750+ types in their range, widely sold through AU industrial distributors. AIMS currently does not stock Holemaker — we focus on Bordo (AU manufactured), Sutton Tools (AU patriot premium), Euroboor (European Weldon specialist), Alpha (impact-rated value) and Maxbor (pilot pin replacements). If you specifically need Holemaker, we can source through our supplier network — call (02) 9773 0122 or use the contact form.
Why does my annular cutter wander off centre?
Wandering is almost always a pilot pin problem. Either the pilot pin is too short for the cutter depth (worn down through use), or the pilot pin is bent or worn, or there's no pilot pin at all. Replace the pilot pin with the matching brand specification. Don't try to drift it back to centre once the cutter has started cutting off-line — withdraw, reposition, restart.
Are mag drill cutters and annular cutters the same thing?
Yes. "Annular cutter", "mag drill bit", "Slugger cutter", "broach cutter", "core drill bit" and "Rotabroach cutter" all refer to the same product class. The naming differences come from brand history — Jancy/Fein established "Slugger" as a brand name, Rotabroach is another brand, and various regions adopted different terminology. The product, the shank standard (3/4 inch Weldon) and the function are all the same.
Where do I buy annular cutters in Australia?
AIMS Industrial stocks 32+ annular cutter products across Bordo (AU), Sutton Tools (AU patriot), Euroboor (European), Alpha (impact-rated) and Maxbor (pilot pins). See the Annular Cutters & Sets collection for the complete range — HSS and TCT, 25mm to 100mm diameters, 25mm to 110mm depth of cut, plus pilot pins, MT2 and Nitto adapters. For brands we don't stock (Holemaker, Hougen, Champion, Milwaukee, HMT, Rotabroach), specialty source through our supplier network on request.
