DeWalt 3-Sided Oscillating Blade (3 PK)

A purpose-built oscillating blade that actually earns its keep

Most oscillating blades claim to be do‑it‑alls. The 3‑sided blade from DeWalt takes a different tack: it’s unapologetically tuned for plunge and rip work in drywall and for those unavoidable nail encounters in wood. After running it through a mix of remodel tasks—cutting single‑gang box openings, trimming drywall around studs, nibbling jambs, and grazing a few nails—I came away appreciating its focused design and predictable behavior.

Design and fitment

A few construction choices define how this blade behaves in the cut:

• Three‑sided profile: The triangular form lets you attack material from multiple angles and square up corners without having to overcut. That’s handy for box cutouts and for trimming in tight quarters.
• 2‑1/8 in cutting width: That dimension neatly matches the width of standard single‑gang electrical boxes, so layout is quick and you don’t end up “stitching” edges with multiple passes.
• Bi‑metal build with a high‑speed steel edge: HSS stands up better than plain carbon steel when you bump into nails or staples. It won’t replace a carbide‑tooth demolition blade for nonstop fasteners, but it’s far more forgiving than typical fine‑tooth steel.
• Chamfered cutting edge: The slight bevel does what it’s supposed to—settles the blade into a plunge with less skittering and sheds chips instead of packing them under the edge.
• Universal, tool‑free fitment: It snapped onto my open‑back oscillating interfaces without drama, including DeWalt and a couple of competitor tools. If your tool is Starlock‑only, you’ll need an adapter; otherwise you’re covered.

The pack includes three identical blades. That matters because users often treat oscillating blades as consumables; with drywall, they last a long time, and with wood/nails they last long enough to justify the set.

Drywall and electrical boxes

This is where the 3‑sided blade shines. The 2‑1/8 in width isn’t a marketing flourish—it’s the reason box cutouts go faster. I score my layout, plunge in at a corner with the chamfered edge, and walk the blade around the line. The triangular shape lets me keep the tool body clear of adjacent studs and still finish square corners without overcutting past the line.

Cut quality is clean with minimal paper fuzz when I run the tool at a mid‑range speed and keep light, even pressure. The chamfered edge helps the blade track straight as it enters; there’s less tendency for the edge to grab and wander compared to squared‑off plunge blades. Dust management is better than average because chips clear to the sides; a vac at the cut line keeps visibility high.

On thicker drywall or layered patches, the blade doesn’t bog. The bi‑metal teeth don’t tear the face paper as readily as aggressive demolition profiles do, so patch work afterward is easier.

Wood with nails

For remodeling, the question is always “What happens when I hit metal?” With framing and trim, I purposely introduced a few 8d nails to the cut path. The HSS edge blunted a touch after repeated nail strikes, but it didn’t crater or lose teeth. Cuts through the surrounding wood remained reasonably quick, and I could finish the task without swapping blades.

Compared to a carbide oscillating blade:
- Cut speed: Slightly slower in hardwoods; not a deal‑breaker for short, controlled cuts.
- Durability on fasteners: HSS survives incidental nail bumps; repeated, deliberate cuts through nails will shorten life. Carbide still wins for heavy demo.
- Smoothness: The bi‑metal tooth form feels less grabby in softwood, which made it easier to follow a scribe line without the tool walking.

If you routinely plunge through unknown fastener fields, go carbide. If you’re mostly in wood and want insurance when you clip a nail head or staple, this blade is a sensible middle ground.

Light metal cuts

Oscillating tools aren’t my first choice for metal, but door skins, thin sheet, and light gauge trim are fair game. The 3‑sided blade was controlled and surprisingly smooth on a steel door hem and some aluminum channel. Keeping the oscillation speed at a medium setting and letting the teeth do the work produced a clean edge with minimal burring. It’s not designed for thick or hardened stock; stay in the “thin and mild” lane and you’ll be fine.

A few tips helped:
- Start with a shallow, guiding plunge so the chamfer sets a track.
- Keep the blade moving laterally to avoid heat buildup.
- A light mist of cutting fluid on longer metal passes keeps the edge sharper.

Control, accuracy, and chip management

The three‑sided geometry buys you control. You can pivot on one corner to nibble to a line, then swing the adjacent edge into the cut without pulling the tool out. That kind of micro‑positioning is harder on narrow, straight‑edge blades that want to sit in a single kerf. The chamfered leading edge further stabilizes the plunge, acting like a shallow ramp.

Chip evacuation is decent. In dense material the gullets aren’t huge, so clearing the cut with a quick back‑out prevents packing. On drywall, chips fling cleanly and visibility stays good. In softwood, the blade leaves a tidy kerf with little fuzzing when you resist the urge to overfeed.

Vibration is on par with other bi‑metal oscillating blades of this size. I didn’t notice excessive chatter unless I overloaded the plunge or hit a hidden screw.

Durability and value

Bi‑metal is a proven compromise between cost and survival. With this blade:
- Drywall: Life is essentially “project‑length.” I cut dozens of openings without noticeable dulling.
- Wood with occasional nails: Expect steady performance for multiple tasks, with gradual slowdown after several direct fastener hits.
- Thin metal: Usable, but each sustained metal cut is a meaningful withdrawal from the sharpness bank.

The three‑pack format makes sense: keep one blade clean for drywall to preserve sharpness, dedicate one to wood where nails are likely, and hold one in reserve for the odd metal encounter. That strategy stretches the value considerably.

Where it falls short

No blade does everything. Keep these limits in mind:
- Not for Starlock‑only tools without an adapter.
- Not a tile/grout/masonry solution; the tooth form and HSS edge aren’t designed for abrasive materials.
- Width is an asset for box cutouts but can be a liability in cramped recesses; a narrower blade still has a place in your kit for tight, intricate work.
- If your day is wall‑to‑wall fasteners, a carbide‑tooth blade will outlast this one and cut faster through hard metal.

Tips for best results

• Mark carefully and pilot the plunge with the chamfered edge just inside your line; then sweep to the mark.
• Use medium oscillation speed for most materials; go slower on metal to reduce heat.
• Let the blade clear chips—short, controlled strokes are faster overall than forcing a deep plunge.
• Keep a clean drywall‑only blade in the pack; once a blade touches wood or metal, retire it from drywall duties to preserve cut quality.

Recommendation

I recommend the DeWalt 3‑sided blade for anyone who routinely cuts drywall openings and needs a capable, forgiving option for wood that may hide a few nails. Its 2‑1/8 in width makes single‑gang box work genuinely faster and cleaner, the chamfered edge improves plunge accuracy, and the bi‑metal/HSS construction holds up to incidental fasteners better than standard steel blades. It isn’t a demolition specialist and it’s not a masonry or tile blade, but within its intended scope it’s reliable, predictable, and efficient. The three‑pack adds practical value and lets you dedicate blades by material, which is how this category of tool earns its keep. If you’re outfitting a remodel kit or doing electrical rough‑ins and patch work, this should be on your short list.