Bosch Glass & Tile Bit Set

Why I picked up this set

A recent bathroom project had me drilling a handful of holes through glazed wall tile and a couple of larger holes in a ceramic planter. I also wanted to revisit a trick from shop class: adding a clean wire pass-through in a glass bottle. That mix of delicate materials is exactly what the Bosch glass-and-tile set is intended for, so I put both the 4-piece and 8-piece assortments to work and tracked how they performed, how quickly they wore, and what techniques made the difference between a clean hole and a scorched, chipped mess.

What’s in the box and what that means on the job

The 4-piece pack covers 1/8, 3/16, 1/4, and 5/16 inch diameters. These are short bits—about 2 inches overall with roughly 1.5 inches of working length. The 8-piece expands the range up to 3/8, 1/2, 5/8, and 3/4 inch, with longer bodies (around 4 inches overall and about 3 inches of working length). That extra length is handy for reaching past trim and into awkward corners, but it also magnifies any side-loading, so technique matters even more with the larger diameters.

These are the spear-point style tile and glass bits with brazed carbide tips. That geometry is purpose-built for brittle materials: the pointed tip helps the bit “bite” through glaze without skating, and the wide cutting edges score and then abrade the material rather than tearing it.

Setup and drilling technique

With tile and glass, the process is half the battle. Here’s what worked consistently for me:

• Use a variable-speed drill in low gear. No hammer action.
• Start slow—think 300–600 RPM for smaller bits, slower yet as diameters increase.
• Keep the bit and surface cool. A spray bottle, water-fed sponge, or a little putty dam to hold a pool of water around the hole helps a lot.
• Light, steady pressure. Let the carbide do the work.
• For glossy surfaces, a strip of painter’s tape or a drilling guide prevents the bit from skating, especially on larger diameters.
• Step up through sizes when you’re aiming for a larger hole; don’t jump straight to 1/2 inch or bigger unless you’re very comfortable doing so.

Following that routine, I had predictable results on glass and ceramic. Deviating from it—going too fast, pushing too hard, or running dry—shortened bit life quickly and, in one case, snapped a tip cleanly.

Performance on glass

This is where the set shines. The 1/8 and 3/16 inch bits gave me crisp, round holes in a wine bottle and a glass vase without star cracks. I started at a shallow angle to get the tip to bite, then leveled out as soon as the point broke the surface. With water on the work and slow speed, the cut stayed cool to the touch and the edges were tidy enough that a light chamfer with a sanding pad was all I needed.

I wouldn’t use the very large diameters on thin glass, but up through 1/4 inch, the control and finish are excellent.

Performance on ceramic tile

Glazed ceramic wall tile is forgiving compared to porcelain, and the smaller bits ran clean and fast for wall anchors. The 1/4 and 5/16 inch bits produced near-chipless holes in standard 1/4-inch-thick tile when I kept the speed down and water present. I was able to make a handful of holes per bit with minimal loss of cutting performance. The short lengths of the 4-piece are actually an advantage here; you’re less likely to lever the bit and stress the tip.

On thicker ceramic (planter walls), the longer bits in the 8-piece are useful. Again, slow and wet is the key. I saw a hint of micro-chipping around one exit hole, which is typical; backing the inside with tape reduced that.

Performance on porcelain tile

Porcelain changes the equation. It’s harder, denser, and more heat-sensitive. The smaller bits (1/8 and 3/16) will still get you started with patience, but the 1/4 inch and above showed accelerated wear. I successfully drilled four 1/4-inch holes in porcelain for a grab bar installation, but those cuts took time and vigilance with cooling. One of the 1/4-inch tips dulled noticeably by the end of the session, and when I got sloppy with pressure on another hole, the brazed tip fractured.

This isn’t a knock unique to this set—spear-point carbide is simply not the ideal match for porcelain if you have more than a couple holes to make. Diamond core bits or electroplated diamond drills are the better, faster, more durable choice for porcelain. The Bosch set will do it in a pinch, but you’re living on borrowed time with the larger diameters.

Accuracy, control, and hole quality

• Start: The spear point engages predictably, especially with tape. On slick glass, the smallest bit starts easiest; for larger holes, I prefer to pilot with 1/8 inch first.
• Tracking: Once you’ve established a dimple, the bit tracks straight. The shorter 4-piece set feels more rigid and less prone to wandering.
• Edge quality: On ceramic and glass, edges are clean with minimal spall. On porcelain, expect some micro-chips; masking tape and backing material help.
• Breakthrough: Easing up at the exit keeps the back side neat. If you can drill from both sides, you’ll get the cleanest result.

Durability and lifespan

These are task-specific bits with a finite lifespan, and they reward good technique. On glass and standard ceramic, bit life is respectable. I made multiple holes per size without noticeable slowdown, as long as I kept things cool. On porcelain, lifespan drops sharply with diameter. The brazed tips are efficient but can’t handle side-loading or overheating; if you lean on the drill, they’ll either glaze over (dull) or, in worst cases, shear at the joint.

If your job list is primarily porcelain or you need to make many large holes, go diamond and don’t look back. For occasional work on glass and ceramic, this set offers decent longevity.

Ergonomics and fit

The shanks fit standard chucks securely. The shorter bits are stubby but easy to control; the longer ones give useful reach behind fixtures but exaggerate any wobble in your grip. Visibility of the cutting point is better than on hole saws, and the spear geometry gives you a clear sense of progress.

Where the two pack sizes make sense

• 4-piece: Ideal for typical anchor and pilot work in ceramic or light glass projects. The shorter length keeps the bit stable and the sizes cover the most common anchors.
• 8-piece: Adds reach and large diameters for pass-throughs or faucet holes, but requires more discipline in technique. I’d keep this for occasional big holes in ceramic; I wouldn’t plan to use the 1/2 inch and up on porcelain more than once or twice.

Alternatives to consider

• Diamond core bits or electroplated diamond drills for porcelain and hard stone. Faster, cooler cutting and dramatically longer life on dense materials.
• Multi-material carbide masonry bits are fine for brick and soft masonry, but they don’t produce as clean a hole in glass and can skate on glazed tile.

Pros

• Clean, controlled starts on glass and glazed ceramic
• Good selection of diameters, with short and long options
• Predictable results when used slow and wet
• Minimal chipping on entry and exit with proper technique

Cons

• Rapid wear and occasional tip failure on porcelain, especially in larger sizes
• Sensitive to heat and side-load; not forgiving of rushed technique
• Short working length on the 4-piece can limit deep reach; long bits magnify user error

Recommendation

I recommend the Bosch glass-and-tile set for homeowners and DIYers who need clean, occasional holes in glass and standard ceramic tile. Used properly—low speed, light pressure, water cooling—it delivers tidy results and reasonable life, especially in the smaller diameters. If your project list includes dense porcelain or you need to produce many large holes, this isn’t the right tool for the job; invest in diamond bits instead. In short: a solid, purpose-built set for glass and ceramic tasks, and a “use with caution” option for porcelain when you’re only drilling a couple holes.