Diamond Core Drill Bit Makita D-44616, 68 mm, M14, for granite marble tile

Makita D-44616 is a 68 mm diamond core drill bit with an M14 connection, engineered for cutting precise circular holes in hard natural and manufactured stone surfaces. The cutter is designed for controlled core drilling through granite, marble and ceramic tile where a high-quality edge and clean finish are required. It is intended for use with angle grinders or core drill adapters that accept an M14 thread and for applications that require a durable diamond-segment cutting edge.

Advantages

The diamond-segment construction provides consistent cutting speed and extended life when used on abrasive stone materials. The 68 mm diameter yields a stable core size for installations such as plumbing penetrations, anchor points and surface fixtures. The M14 connection enables direct mounting to many angle grinders and compatible adapters, reducing the need for additional couplings. The design focuses on producing clean, chip-minimized holes with minimal need for secondary finishing.

Suitable for

• Drilling 68 mm core holes in granite worktops and slabs
• Creating openings in marble surfaces for fixtures and pipes
• Cutting circular holes in ceramic and porcelain tiles for plumbing and electrical installations
• On-site renovation and repair tasks requiring precise round holes in stone materials

When it may not be suitable

This core bit is intended for hard stone and tile; it is not optimized for general-purpose drilling in wood, metal or soft plastics. For deep structural core drilling beyond the bit’s cutting depth or for very large-diameter holes, professional core drill rigs and bits designed for that scale should be used. Using the bit on incompatible machines or without suitable cooling/technique can shorten tool life and affect hole quality.

Key specifications

• Cutting diameter: 68 mm
• Connection type: M14 threaded mount for direct attachment to compatible angle grinders and adapters
• Material: diamond-segment cutting edge for masonry and stone
• Primary applications: granite, marble, ceramic and porcelain tile

How to use

Fit the diamond core bit securely to an angle grinder or adapter with an M14 thread, following the machine manufacturer’s mounting instructions and safety checks. Position the bit at the marked drilling point and start at low speed to establish a guide groove, then increase speed and apply steady, even pressure. Use water cooling or intermittent cutting to reduce heat build-up and prolong diamond life when drilling stone or tile; follow recommended safety equipment such as eye protection, dust control and gloves. Withdraw the bit periodically to remove debris and inspect the cutting edge.

What to consider before purchase

• Ensure your grinder or adapter accepts an M14 threaded connection
• Confirm the 68 mm diameter matches the required hole size for your installation
• Assess whether water cooling or dry cutting is appropriate for your chosen material and work environment
• Check machine maximum speed and compatibility with diamond core bits for safe operation

Usage recommendations

For best results on granite and marble, use steady low-to-medium speed, maintain water cooling where possible, and allow the diamond segments to cut without excessive force. For tiles, start with a shallow guide groove and proceed gently to avoid cracking. Replace the bit when cutting performance noticeably decreases.