Bosch 1-1/4 in. StarlockMax Carbide Plunge Cut Blade

I reached for this Bosch carbide plunge blade to solve a classic remodel problem: a leaking, century-old galvanized supply line tucked behind a plaster wall where a grinder or reciprocating saw would have been collateral damage. The blade didn’t chew through the pipe like a miracle, but it did exactly what I needed—make a controlled plunge in a tight cavity, keep vibration to a minimum, and get the cut done without destroying everything around it. That’s where this accessory shines.

Setup and compatibility

The StarlockMax mount is a big part of the experience. On my StarlockMax multi-tool, the snap-on fit is solid and fuss-free. There’s no screw to loosen and re-tighten, and torque transfer feels immediate. If you’re new to Starlock, note that StarlockMax is the largest of the Starlock interfaces; it does not fit non-Starlock tools or most older OIS-style mounts. That’s a hard boundary. If your tool isn’t StarlockMax-compatible, this blade is not for you.

Identification is straightforward. The laser-etching stays legible after use, and Bosch’s color coding makes it easy to grab the right cutter from a pile.

Build and geometry

This is a 1-1/4-inch-wide plunge blade with carbide teeth and a listed immersion depth of 1.5 inches. The plate measures roughly 1/8 inch thick, which is stout for an oscillating accessory. That extra thickness translates to low flex and straighter tracking during plunges. The kerf is naturally wider, and you feel more mass in the cut, especially in metal. The tip geometry is genuinely useful; it starts cleanly without walking across the surface, which is crucial when you’re working near finished surfaces.

Fit and finish are excellent. The Swiss-made stamp might not change performance on its own, but the consistent brazing and tooth alignment here are what let a small blade stand up to abuse.

Cutting performance

• Metal and embedded fasteners: The blade is rated for nail, staple, bar, and pipe cutting, and it does it credibly—within the limits of an oscillating tool. On thin-section steel, nails, screws, and copper, it’s quick and predictable. On 1/2-inch galvanized steel pipe, it’s slow but steady. Expect sparks near the end of a cut and be ready for heat. I also tested on rebar as an abuse case; it got through in short order for its size. The tradeoff is tooth wear: heavy steel stock eats carbide. Plan your workflow so you use this blade for controlled plunge access or where space is constrained, and leave long, straight steel cuts to a grinder or recip saw.

• Fiber cement and masonry-adjacent tasks: This blade excels in fiber cement siding and backer board. The ability to plunge a clean square cutout with a fraction of the dust of a grinder is a big win on occupied jobsites. Dust isn’t eliminated, but it’s far more manageable. It also nibbles through ceramic tile for small modifications, though it’s not a substitute for a diamond wheel or a wet saw for longer, clean finishes—expect some chipping and go slowly.

• Wood with nails: In demolition and remodel scenarios—old trim, subfloor patches, or framing with surprise fasteners—the blade keeps working where a wood-only blade would be done after the first nail. It’s not a fast cutter in clean, dry lumber and it can scorch in resinous stock. I treat it as a “mixed-material insurance” blade: run it when you know metal is coming.

• Drywall and plastics: It’s more than capable here, but this is overkill unless you’re also expecting to hit metal. If you cut a lot of drywall, a fine-tooth wood/plastic blade is faster and leaves a cleaner edge.

Speed, control, and vibration

Oscillating tools are all about control, and the StarlockMax interface helps. Vibration at the handle is low, and the blade tracks true. I could start plunge cuts one-handed without the tool skittering off the mark. That’s valuable when you’re cutting near painted trim or finished tile. Cutting speed is governed by heat in metal: medium oscillation speed, light pressure, and a short rest mid-cut will significantly extend tooth life. Side loading is the enemy—let the teeth do the work.

Durability and lifespan

Bosch claims up to 30 times the life compared with standard bi-metal blades. In mixed-material and nail-heavy work, that feels directionally right—carbide outlasts bi-metal by a wide margin. In heavy steel, you can dull or chip teeth after a handful of demanding cuts. That’s not a knock; it’s the reality of a small oscillating blade doing big-tool tasks. After it loses its bite on steel, it often still has plenty of life for softer duties like drywall, plastics, or even light wood trimming.

Heat management is everything. A drop of cutting fluid on steel, a slightly lower speed setting, and a pause to cool will buy you more life. For cement board, connect a vac at the cut line and keep speeds moderate to reduce airborne silica and tooth wear.

Precision and finish quality

The 1-1/4-inch width gives good line of sight and control along a scribe. The 1.5-inch immersion depth is enough for common tasks like notching jambs for tile or getting through typical studs without over-penetrating. In metal, kerf edges are respectable with minimal burrs; in wood, edges can scorch if you push too hard, so swap to a wood tooth blade when finish matters.

Value

It’s a premium, single-pack accessory with a premium price. If your work routinely involves mixed materials in tight quarters—remodelers, electricians, plumbers, maintenance pros—the value is clear. You spend more up front, but you carry one blade that can safely hit the unknown without stopping the job. If you’re mostly cutting clean wood or doing long, straight metal cuts, there are cheaper, faster tools and blades for those tasks.

One caveat: StarlockMax compatibility. If your multi-tool doesn’t support StarlockMax, there’s no workaround. That limitation will be a non-starter for some users.

Best practices

• Use medium speed on steel; slow down as you break through.
• Keep pressure light and consistent; avoid prying or side loading.
• Add a dab of cutting fluid on metal to reduce heat.
• For ceramic, score first and advance in short plunges; expect some chipping.
• Pair with dust extraction for fiber cement; wear a respirator when necessary.
• Swap to a wood-specific blade for clean cuts in lumber to avoid scorch.

What I’d change

• Broader compatibility would help, but that’s inherent to StarlockMax. If you’re in that ecosystem, this blade makes sense; if you’re not, you’re locked out.
• A slightly longer immersion option would expand utility for thicker stock. The current depth covers most tasks but occasionally feels tight on larger pipe or doubled framing.

Bottom line

In my kit, this Bosch carbide plunge blade has become the “unknowns” blade—the one I install when I might hit metal, need a precise plunge in a finished space, or want a cleaner, lower-dust way to make a square opening in cement board. It’s not the fastest option in any single material, and it’s not cheap, but it consistently trades speed for control and jobsite safety. That’s a trade I’m happy to make in tight or delicate scenarios.

Recommendation: I recommend this blade to anyone already using a StarlockMax multi-tool who needs a compact, durable solution for mixed-material plunge cuts in tight spaces. It’s a reliable problem-solver for remodelers and trades who value control and versatility over raw speed. If your tool isn’t StarlockMax-compatible or your work is mostly clean wood or long metal cuts, look elsewhere. For the right user, it earns its keep.