DeWalt 3-Piece Titanium Nitride Coating Impact Ready Step Drill Bit Set

Why I reached for this step bit set

I spend a lot of time opening up sheet metal, punching clean holes in electrical boxes, and sizing grommet openings in plastic enclosures. A good step bit saves time and space in the pouch. I put DeWalt’s impact‑rated step bit set to work over a few weeks on mild steel, aluminum, PVC, and thin plywood, both in the shop and on-site with an impact driver. The short version: it’s a fast-cutting, durable set with thoughtful details, provided you respect step bits’ usual limitations and use the right technique.

Build and design

This is a three-piece set with a 1/4 in. hex shank, optimized for both drills and impact drivers. Each bit is titanium nitride (TiN) coated, dual‑fluted, and has a split-point tip. Laser‑engraved markings show the step sizes.

A few design notes stood out in use:

• The split-point nose tracks well. On clean steel and painted panel covers, I didn’t need pilot holes. The tip bites without skating as long as you keep a steady hand and let the bit get a purchase.
• Dual‑spiral flutes clear chips better than single‑flute styles and noticeably reduce heat. You feel it in the way the bit stays cutting rather than burnishing.
• The TiN coating holds up. After dozens of holes in 18–14 ga. mild steel and aluminum, the edges still felt sharp and the coating hadn’t polished off the cutting lands.
• The laser‑engraved steps are actually legible mid‑cut. They don’t rub off like ink; a quick wipe clears oil and chips so you can stop right on size.

Across the three bits, you get coverage from 1/8 up to 7/8 in. in fractional steps (1/8, 5/32, 3/16 … through 7/8). That range is ideal for knockout alternatives, conduit fittings up to 1/2 trade size, panel indicators, and common grommets.

In use: drills vs. impact drivers

These carry an impact rating and a hex shank that locks into a quick‑change collet. I used them mostly in a compact drill/driver, but also with an 18V impact.

• In a drill: Best control and cleanest holes. Run at low to medium speed and moderate feed pressure. For steel, drop into the drill’s low gear. The bit cuts fast enough that you don’t feel tempted to goose the RPM.
• In an impact driver: Surprisingly capable. If you keep the trigger in check and let the bit do the work, it won’t chatter excessively. The dual flutes seem to help avoid the “hammering stall” you get with some step bits. I still prefer a drill for precise, burr‑light holes, but on a lift or ladder where an impact is already in hand, this set doesn’t complain.

Practical note: With any step bit, you’re cutting larger diameters at the outer steps, so surface speed rises quickly. For steel, keep RPM conservative and use cutting fluid. The bit rewards patience with cooler, sharper cutting.

Material performance

• Mild steel (18–14 ga.): Excellent. Starts cleanly, pulls a continuous chip, and leaves a round hole with modest burrs. A quick deburr pass with the next step or a countersink cleans the edge.
• Stainless (thin sheet, e.g., 304/430 at 20–18 ga.): Works, but go slow and use fluid. Stainless will punish high RPM. I got usable holes for control boxes but wouldn’t choose a step bit for heavier stainless plate.
• Aluminum: Very good. The dual flutes evacuate the gummy chip reasonably well; a touch of wax helps keep the lands from loading.
• Plastics (PVC, ABS, acrylic): Excellent, smooth edges and no cracking when I slowed the RPM. Great for grommet holes in project boxes.
• Wood and composites: It works in thin plywood and laminate for ad‑hoc sizing, but it’s not a replacement for Forstners or hole saws if you want crisp holes in thicker stock.

Accuracy and step markings

Step bits rely on you to stop at the right land. The engraved marks here are genuinely helpful. On bright‑finished TiN, the dark engraving contrasts well. Even after a few oily sessions, the marks remained readable.

Hole size accuracy was on point for me. Fractional steps measured within a few thousandths in sheet material. If you need an exact press fit, sneak up on size and test. For grommets, the sizing was spot on against manufacturer charts.

Because this is a dual‑flute design, the step transition has two cutting edges entering at once, which can “grab” slightly at the moment a new diameter engages. It’s not a defect; it’s the nature of dual flutes. Keep a firm wrist and steady feed—particularly in thin sheet—and the hole stays round and true.

Durability and maintenance

TiN is a surface coating. It reduces friction and wear but doesn’t replace good technique. After dozens of holes in steel and aluminum, I saw normal polishing on the steps but no chipping. Edges stayed keen longer than my older black‑oxide step bits.

A few longevity tips:

• Use cutting fluid on metals. You’ll double the life of the edges.
• Let chips evacuate. The dual flutes help, but if you pack the gullets, back off and clear them.
• Avoid excessive downward force at large diameters. Let the outer lips cut; don’t try to “punch” through.
• Expect to deburr. Most step‑bit holes in metal benefit from a light pass to kiss off the exit burr.

Resharpening a step bit is possible with a fine stone if you know what you’re doing, but it’s easy to change geometry. Given the durability I saw, I’d plan to use them as consumables and retire them when they stop cutting cleanly.

Limitations worth noting

• Not for thick plate. Step bits shine in sheet material. Once the workpiece is thicker than a step height, you’re rubbing more than cutting and risk grabbing.
• Dual‑flute behavior. Faster cuts and better chip flow come with a touch more grab at step transitions compared to classic single‑flute Unibit‑style tools. It’s manageable but noticeable.
• Impact use is context‑dependent. The bits are rated for it and do fine, but if you need the cleanest possible edge or are working in stainless, a drill at controlled RPM is still the better choice.

None of these are deal‑breakers; they’re the usual tradeoffs anyone familiar with step bits expects.

Who this set fits best

• Electricians and HVAC techs who live out of an impact driver and need fast, clean holes in sheet metal and panels.
• Fabricators and makers who want wide size coverage without swapping a dozen twist bits.
• DIYers looking to size grommet and toggle switch holes in project boxes, auto interiors, and thin stock.

The coverage from 1/8 to 7/8 in. across three bits is especially convenient on a cart or in a pouch—far fewer trips back to the box.

Alternatives to consider

• Single‑flute designs (e.g., classic Unibit) cut a bit smoother at each step and are less grabby in thin sheet, at the expense of slower chip evacuation.
• Non‑coated or black‑oxide step bits are cheaper but wear faster in steel. If you drill metals often, TiN earns its keep.
• 3‑flat or round shanks are fine in keyed chucks, but if you rely on quick‑change collets and impacts, the 1/4 in. hex here is the better choice.

Bottom line and recommendation

This DeWalt step bit set hits the right notes: quick starts from the split point, fast cutting with the dual flutes, durable TiN coating, clear laser markings, and a secure 1/4 in. hex that genuinely works in both drills and impacts. Across steel, aluminum, and plastics, it gave me clean, accurately sized holes with predictable behavior and no drama. Respect the usual limits (thin materials, sane RPM, cutting fluid), and it rewards you with speed and long life.

I recommend this set. If you need broad hole coverage in a compact kit and often work out of an impact driver, it’s a reliable, impact‑rated option that keeps up with jobsite pace while maintaining the control and accuracy I expect from a good step bit.