4.5in Dry Diamond Core Drill Bit for Tile - Precise 115mm Holes

In this review the author tests the 4.5in Dry Diamond Hole Saw and finds it best suited for tradespeople and knowledgeable DIYers who need precise 4.5in (115mm) holes in hard surfaces. The single biggest reason to buy is its ability to cut clean, accurately sized openings in ceramic, porcelain, marble and granite when used with a compatible angle grinder or wet polisher; that real-world cutting performance is why this drill bit earned a solid recommendation here. The reviewer notes it works without requiring heavy pressure and that cooling and proper technique are important for long life.

Key Features

• 115mm Diameter: Cuts a true 4.5in hole useful for faucets, drains and duct openings with consistent sizing for retrofit work.
• 5/8-11 Thread Fit: Threads directly onto most angle grinders and wet polishers so it is simple to install and swap between tools.
• Diamond Tipped Edge: High-technology diamond grit delivers sharp cutting action on porcelain, ceramic and natural stone while resisting rapid wear.
• Dry Cutting Design: Intended for dry use with a recommended technique and intermittent cooling, which avoids the need for a wet rig in many applications.
• Debris Slot: The slot in the side helps clear slurry and debris so holes stay accurate and the bit keeps cutting rather than packing up.
• 2in Max Cutting Depth: Reaches through typical tile and thin stone countertops for common plumbing and electrical openings.

Who It's For

This bit is aimed at installers, plumbers, and experienced DIYers who already own an angle grinder or polisher and need a reliable 4.5in hole saw for tile, marble, granite and similar materials. It is especially useful when installing faucets, shower fittings, drains or routing small ducts where a neat round penetration is required.

It is not the best choice for beginners who have never used a high-speed grinder on tile without a guide, or for tasks that demand wet continuous cutting rigs for large stone slabs. Those users should consider guided drilling setups or wet core systems better suited to extensive stone work.

Pros & Cons

Pros

• Performs well on porcelain and granite when used with the correct technique and cooling, producing accurate 4.5in holes.
• Attaches directly to common angle grinders via the 5/8-11 female thread, making tool changes straightforward.
• Diamond-tipped edge and side slot speed debris removal and extend usable life compared with plain metal bits.

Cons

• Dry cutting generates heat; the bit needs intermittent cooling or dips in water to avoid overheating and to prolong life.
• Performance varies by material hardness and operator technique, so cutting speed can feel slow on very hard granite to some users.

Specifications

Diameter	4.5 in (115mm)
Connection	5/8-11 female thread
Max cutting depth	2 in (approx)
Diamond height	0.59 in (15mm)
Total height	2.4 in (61mm)
Compatible materials	Ceramic, porcelain, marble, granite, natural stone, glass tiles

Our Verdict

The 4.5in Dry Diamond Core Drill Bit is a practical, value-minded choice for professionals and experienced DIYers who need neat 115mm holes in tile and stone without a wet rig. It pairs easily with angle grinders and, when used with the recommended 45 degree start and intermittent cooling, cuts accurately and lasts well enough to justify the purchase for occasional to regular jobs.

Frequently Asked Questions

Will this fit my angle grinder?
Yes, it uses a standard 5/8-11 female thread designed to attach to most angle grinders and wet polishers that accept threaded accessories.

Can it cut through thick granite countertops?
It can penetrate stone up to its maximum cutting depth of about 2in, but very thick or extremely hard granite may cut slowly and benefit from wet core tools or staged cuts and cooling.

Do I need water while cutting?
The bit is designed for dry use but will get hot; intermittent dips in water or stopping to cool the bit is recommended to prevent overheating and extend diamond life.