Core drill bits · core bits · diamond crowns
Diamond core drill bits. A core bit that fits your rig and your concrete.
Core bits for reinforced concrete, masonry and porcelain – with the thread that fits your machine. From Ø 12 mm cable penetrations to large ventilation and process openings.
- 1 1/4" UNC · 1/2" BSPM16 · M14 · SDS-plus
- Custom lengthsand extensions with the same thread
- Starter kitsfor electricians and installers
- Tube retippingnew segments, same body
Core bit configurator
Five decisions and you have a specification
Material, cooling, diameter, wall thickness and thread. We suggest the mounting and length and warn you when an extension is needed. Add the finished specification to your quote request.
Your specification
—
- Diameter
- Working length
- Mounting
- Segment
Indicative selection based on market standards. A technical advisor confirms the specification.
Core bit series
Choose a series, diameter and length
Know what you need? Filter the series by material, machine and thread, pick the diameter and working length and add it to your quote.
No series match these filters. We make custom diameters and lengths to order – describe the job.
Ask for a custom sizeThread and mounting chart
Which thread fits your core drill
A thread that does not fit is the most common reason for returns. Check your machine's spindle before you order – if you run several systems, we will supply an adapter.
| Mounting | Typical diameters [mm] | Cooling | Machines | Application |
|---|---|---|---|---|
| 1 1/4" UNC | 32–500 and above | wet / dry | rigs on stands and hand-held drills (market standard) | openings in reinforced concrete, service penetrations |
| 1/2" BSP (G ½") | 8–62 | wet | hand-held drills, small rigs on stands | anchors, cable penetrations, small pipes |
| M16 | 32–162 | dry | dry hand-held drills, with an SDS adapter | masonry, brick, block, aerated concrete |
| M16 + SDS-plus | 68 · 82 · 102 | dry | SDS-plus rotary hammer (no hammer action) | electrical boxes, sockets |
| M14 | 6–100 | dry / wet | angle grinder | porcelain, tiles, stone – taps, drains |
| Adapters | — | — | 1/2" BSP ↔ 1 1/4" UNC, M16 ↔ 1 1/4" UNC, proprietary systems – others on request | one core bit for several machines |
Machine manufacturers' system names are used only to describe compatibility. How to measure your core drill's thread and when an adapter is enough – guide: core bit thread chart.
Which diameter to choose
| Application | Item | Core bit Ø [mm] |
|---|---|---|
| Electrical box | Ø 60 box | 68 |
| Large / junction box | Ø 80 box | 82 |
| Cable duct, conduit | Ø 20–40 | 25–52 |
| EV charger / PV supply | cable / protective conduit | 52–82 |
| Drain DN 50 | Ø 50 pipe | 62–72 |
| Drain DN 110 | Ø 110 pipe | 122–132 |
| Drain DN 160 | Ø 160 pipe | 182 |
| Ventilation | Ø 125 duct | 142–152 |
| Ventilation | Ø 160 duct | 182 |
| Ventilation | Ø 200 duct | 225 |
Indicative – with clearance for insulation and sealing. For fire-stopped penetrations, size the hole to the sealing system. How to work out the clearance and choose a core bit: hole diameters for building services – with a calculator.
Starter kits
Everything for your first job
The most-ordered diameters in one kit – instead of putting it together piece by piece.
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Electrical · EV · PV
Electrician kit
- Ø 68 box core bit, M16
- Ø 82 box core bit, M16
- SDS-plus adapter with centre drill
- Ø 52 cable penetration, M16
price on request
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HVAC · plumbing
Installer kit
- Ø 62 · 82 · 132 1 1/4" UNC, L 450
- Ø 152 · 182 1 1/4" UNC, L 450
- Extension 300 mm, 1 1/4" UNC
- Adapter 1/2" BSP ↔ 1 1/4" UNC
price on request
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Anchoring · cables
Anchor kit
- Ø 14 · 16 · 18 1/2" BSP, L 300
- Ø 20 · 25 · 32 1/2" BSP, L 400
- Ø 42 1/2" BSP, L 400
- Carry case
price on request
What drillers come to us with
Four problems that stop the drilling
Each one costs time on site. Each one comes from the choice of core bit, thread or operating parameters.
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The core bit jams
Cause: too little side clearance on the segments, slurry not flushed out, rig not square.
Fix: segments with side clearance, constant water flow, a stand anchored on the hole axis.
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Segments torn off on rebar
Cause: impact when hitting steel, too much feed pressure, dry drilling.
Fix: impact-resistant grit, less pressure on the bar, water cooling.
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The thread does not fit the machine
Cause: different systems: 1 1/4" UNC, 1/2" BSP, M16, proprietary systems.
Fix: check the thread chart, order an adapter or a core bit with the right shank.
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It stopped drilling
Cause: glazed segments – the bond is too hard for the aggregate.
Fix: dress the segments in an abrasive material; long term, a softer bond.
Core bit retipping
Is the tube straight? It will come back with new segments.
We replace the segments, straighten the tube and check the thread – on other brands' core bits too. Every bit comes back with a report. You ship the bits to us after we have agreed the scope.
- Price
- on request, confirmed after inspection
- Lead time
- 1–2 working days + shipping
Quote request
Send your list of holes – we will match the core bits
Items added from the configurator and the series list appear in this form automatically. Have a hole schedule from your project? Describe it in the message.
- 01Diameters, lengths and thread
- 02An advisor confirms the selection
- 03Quotation with delivery terms
What thread does a diamond core bit have?
Most wet core drilling rigs have a 1 1/4" UNC spindle. Small core bits, usually up to Ø 62 mm, have a 1/2" BSP thread. Dry core bits for masonry often use M16, and porcelain bits for angle grinders use M14. Adapters connect the systems. See the thread chart.
Which core bit for 68 mm electrical boxes?
A Ø 68 mm dry core bit with M16 mounting and an SDS-plus adapter with a centre drill. For masonry and light concrete without rebar. Switch the rotary hammer to drilling without hammer action.
Wet or dry?
Reinforced concrete and concrete – wet: water cools the segments and flushes the slurry, so the bit does not jam. Masonry, brick and block are drilled dry with core bits designed for it, using dust extraction. Details and a calculator: dry or wet core drilling.
Why does a core bit jam?
Usually because the slurry is not flushed out, the segments have too little side clearance or the rig is not square. Constant water flow, a stand anchored on the hole axis and segments with side clearance solve it.
How do I drill deeper than the length of the core bit?
Drill to full length, remove the core and add an extension with the same thread. For thick walls it is better to choose a longer core bit from the start – the configurator suggests the length and extension. Step by step: core drilling through thick walls.
How do I drill through rebar?
Wet, with less feed pressure when the bit hits steel and a constant speed. The core bit needs impact-resistant grit – standard concrete segments break off quickly.
Do you retip core bits?
Yes, if the tube is straight and free of cracks. We replace the segments, check the thread and run-out and issue a report. Request core bit retipping.