Diamond core bits for dry and wet cutting

Diamond Core Bits for Tiles and Natural Stone from Karl Dahm

Diamond core bits are essential tools for any professional tiler. Whether you're working with wall tiles, porcelain stoneware, natural stone, or granite – clean, precise, and material-friendly drilling requires specialised tools you can rely on in everyday site work. The Karl Dahm online shop offers a wide range of high-quality diamond core bits for both dry and wet cutting, including the latest MATRIXTEC technology and well-thought-out core bit sets.

Why Choose Diamond Core Bits from Karl Dahm?

Precision, durability, and versatility define our diamond core bits. Thanks to industrial-grade diamond segments, they ensure precise drilling without chipping – even on delicate surfaces like porcelain stoneware or glazed tiles.

Another advantage: our core bits are designed specifically for professional tradespeople. They impress with:

• High drilling speed and long service life

• Clean edges and minimal heat build-up

• Compatibility with angle grinders, cordless screwdrivers, or drilling rigs

• Water feed or paraffin cooling options for dust-free drilling

It's not just about diameter or mounting type – what really matters is that the core bit is optimally suited to the material. Our range includes various segment heights, coatings, cooling technologies, and connection types.

Dry Core Bits: Flexible and Powerful

Dry core bits are ideal for mobile applications or indoor use without water supply. Particularly popular: the Gold Edition with M14 connection – suitable for use with angle grinders. These bits easily cut through hard materials like porcelain stoneware, natural stone, or marble.

Thanks to their thin-walled design, they operate especially quickly and efficiently. An integrated wax cooling system in the drill segment helps regulate temperature and protect the diamonds. Typical diameters range from 6 to 120 mm – ideal for socket drilling, water connections, or special applications.

The M14 threaded connection allows for fast mounting on common angle grinders. Models with paraffin cooling or bit connections are also perfect for cordless screwdriver use.

A highlight is the dry core bit set Art.-No. 50234, which bundles six of the most common diameters in a practical transport case. The diamond segments provide reliably precise results – even on tough wall tiles or natural stone.

Wet Core Bits: Precise Results for Hard Materials

For sensitive or very hard materials, we recommend wet cutting with continuous water cooling. Karl Dahm wet core bits are ideal for porcelain stoneware, tiles, granite, or glass.

With the matching KDB-200 drill stand (Art.-No. 40103), serial drilling can also be carried out with precision and efficiency. Thanks to the integrated water tank and pump, the core bit remains constantly cooled throughout the application. This protects the material from stress cracks and significantly extends the bit’s service life.

Our Bohrmeister series offers outstanding performance and is equipped with an R 1/2" thread for stationary drilling systems. Diameters up to 130 mm are possible – ideal for large-format panels or bathroom renovations.

Another popular wet core bit set is Art.-No. 50101, consisting of five different diameters and the proven sharpening stone (Art.-No. 20050) for diamond reactivation – ideal for regular use on job sites.

MATRIXTEC Diamond Core Bits: Advanced Technology for Professionals

The latest innovation in dry drilling is MATRIXTEC. These core bits feature a high-density diamond matrix for particularly even drilling results and maximum service life.

Ideal in combination with an angle grinder or cordless screwdriver – for drilling in porcelain stoneware, natural stone, ceramic, or hard composite materials. A standout feature is the controlled drilling behaviour: MATRIXTEC significantly reduces vibration and improves cutting control.

A proven example: the MATRIXTEC core bit set Art.-No. 50841, consisting of several diameters including a stainless-steel pilot guide. This technology is especially valuable in professional interior construction or kitchen installations.

Diamond Core Bit Sets: Smart Combinations

If you regularly need multiple diameters or want to be prepared for various job site scenarios, our core bit sets are the perfect choice.

Whether the Gold Edition in a practical case (e.g. Art.-No. 50234) or the MATRIXTEC Set (e.g. Art.-No. 50841) – most sets contain 6 to 8 common diameters. Many include a stainless-steel pilot guide or a cooling gel system for dust-free work. Sets with bit connections and paraffin cooling for cordless screwdrivers are also available.

The Art.-No. 50330 set, for example, combines innovative paraffin cooling with a simple bit connection. Perfect for both DIYers and professionals. Cooling gel (Art.-No. 50368) helps minimise dust and cool the core bit during operation.

Karl Dahm Advice & Service

Not sure which core bit is best for your material? Our expert advisers are happy to help by phone at +49 8667 878-0 or by email at info@dahm-werkzeuge.de. You can also send us a sample of your material – we’ll find the perfect solution for your needs.

Take advantage of our fast shipping: order by 2 p.m. on weekdays and your goods usually leave our warehouse the same day.

FAQ: Frequently Asked Questions about Diamond Drill Bits

What are dry core bits best suited for?
Dry core bits are specifically designed for quick and flexible use without water cooling. They are ideal for smaller drilling diameters, especially in tiles, porcelain stoneware, ceramics, and similar materials. Their design makes them perfectly compatible with angle grinders, which are portable and easy to handle. Dry core bits are particularly practical during renovation or installation work where there is no external water supply available. They allow for precise and clean drilling without the added slip hazard caused by water.

Why are wet core bits gentler on materials?
Wet core bits are continuously cooled with water during the drilling process. This constant cooling prevents the segment and material from overheating. Especially with delicate surfaces such as glass, natural stone, marble or premium tiles, this is essential to avoid stress cracks, chipping, or discolouration. Water dissipates the generated frictional heat, reduces dust, and ensures a clean cutting edge. This not only extends the life of the drill bit but also preserves the quality and aesthetics of the borehole.

What makes MATRIXTEC core bits different?
MATRIXTEC core bits feature a specially optimised diamond structure. This allows for even and controlled wear of the diamond segments, resulting in significantly longer service life compared to conventional models. They also offer excellent running smoothness, which means reduced vibration and better control during drilling. These properties make MATRIXTEC core bits particularly suitable for very hard tile materials, porcelain stoneware, or aggressive composites, where precision and durability are essential.

Which core bits can be used with cordless drills?
Core bits with special hex shank fittings, such as the model with item number 50230, are designed for use with standard cordless drills. This solution is ideal for mobile use on construction sites where mains power isn’t always available. The combination of cordless drill and matching core bits enables flexible and convenient work, especially for smaller holes in tiles, plasterboard or wood. It is important that the drill delivers enough torque to ensure a clean hole.

What is the role of paraffin in the drill segment?
Paraffin is an innovative additive material used in some diamond segments. During drilling, it melts due to the heat generated and acts as internal cooling. This significantly reduces the temperature in the segment, preventing overheating and premature wear. This is particularly advantageous for dry drilling, where no external water cooling is used. Paraffin also improves lubrication between the bit and the material, making drilling easier and extending the bit's service life.

Can diamond drill bits be re-sharpened?
Yes, diamond core bits can be re-sharpened or reactivated under certain conditions. For this, the Karl Dahm sharpening stone (item no. 20050) is ideal. It exposes embedded diamond particles on the surface and removes deposits that reduce cutting performance. This treatment is simple and significantly extends the life of the drill bits. It’s important that sharpening is done regularly and properly for best results.

Is there a maximum drilling depth?
Most diamond core bits are designed for a maximum drilling depth of approximately 60 mm. For deeper holes, Karl Dahm offers special extensions or drill bits specifically designed for greater depths. When drilling deep holes, it is also important to ensure proper cooling and to use a stable drill stand to guarantee precision and safety.

Why should I buy a drill bit set instead of individual bits?
A core bit set offers several advantages over buying individual bits. It includes a selection of different diameters suited to a variety of tasks. Sets often come with useful accessories such as drill guides, adaptors or a sturdy transport case. This saves time and money by allowing you to respond flexibly to different site conditions without needing to order new bits each time. Sets are also usually more economical than buying the same bits individually.

Can I drill near the edge of tiles?
Yes, drilling close to the edge of tiles is possible with high-quality Karl Dahm diamond core bits. What’s important is a clean and stable starting point and using a drill guide or centring ring to avoid slipping. With slow and controlled operation, edge drilling can be performed without chipping or damaging the tile. This is especially useful when installing sockets, pipe feedthroughs or other fittings.

Which diameter is suitable for socket cut-outs?
The most common diameters for socket openings are 68 mm and 70 mm. These sizes fit most standard wall boxes and are available from Karl Dahm as both dry and wet core bits. The choice of drill bit depends on the material and the required level of precision.

Which machines are compatible with the drill bits?
Karl Dahm diamond drill bits are highly versatile and compatible with various tools:

• Angle grinders with the appropriate adaptor

• Standard drills with R 1/2" threaded connections

• Cordless drills (for bits with hex shank fitting)

• Special drill stands like the KDB-200 for precise and repeatable drilling

This flexibility makes them suitable for a wide range of applications and site conditions.

What makes the KDB-200 drill stand special?
The KDB-200 is a high-quality, stable and mobile drill stand specifically designed for use with diamond core bits. It features an integrated water supply that ensures continuous cooling during wet drilling. The stand allows for precise and low-effort drilling, even for serial holes or thick materials. Its robust construction makes it ideal for professional tradespeople or tilers who value efficiency and accuracy.

Are there drill bits for glass and mosaic?
Yes, the Karl Dahm range includes special wet core bits that are suitable for very delicate materials such as glass tiles and mosaic. The combination of fine diamond grit and water cooling ensures that the glass surface doesn’t crack or chip. Wet drilling is always recommended for these materials to protect them as much as possible.

How should drill bits be stored?
Diamond core bits should always be stored dry, clean, and protected from moisture and dust. The original transport cases or specially designed storage boxes are ideal, as they protect against mechanical damage and keep the bits securely in place. Proper storage extends the tool’s life and prevents corrosion on metal parts.

What should I do if the drill bit no longer cuts?
If a drill bit becomes dull and no longer cuts cleanly, treatment with the Karl Dahm sharpening stone (item no. 20050) usually helps. This exposes the diamond particles on the surface again and improves cutting performance. If this does not help, it may be time to switch to a new bit or one with coarser segments, as the diamonds may have worn down. Regular maintenance and inspection improve both efficiency and lifespan of the tool.

Trust Karl Dahm – for precise results, durable tools, and professional support.