DeWalt #8 Replacement Drill Bit & Countersink

Why I reached for this bit

I spend a lot of time toggling between drilling a clearance hole, countersinking, and then driving screws during cabinet and trim installs. That’s exactly where the DeWalt #8 countersink bit earns its place in my kit. It’s a simple, purpose-built replacement component for flip-drive drill/countersink setups, and it’s designed to do one thing cleanly: drill a #8 clearance hole and cut a neat countersink in wood, fast.

Setup and compatibility

This is a single-piece replacement with a 1/4-inch hex shank, so it drops straight into quick-change chucks and the flip-drive style units many of us use on site. The length (about 3-1/2 inches overall) keeps it compact, which I appreciate when working inside cabinets and toe-kicks. If you’re using a flip-drive that relies on a set-screw collar to control depth, this bit plays nice—just transfer the collar to control how deep the countersink lands.

A couple of important sizing notes:
- Drill size is 11/64 inch, which corresponds to a proper clearance hole for #8 screws. That means the threads won’t grab the top piece.
- The countersink is a multi-cutter design set at 60 degrees. More on how that looks in practice below.

If you’re expecting a tapered pilot for the lower piece, this isn’t that tool. It’s a clearance-and-countersink combo for the top board. For hardwood assemblies, I still predrill a pilot in the mating piece when needed.

In use: clean starts, quick cuts

The black oxide split-point bit starts on contact without skating. On paint-grade poplar face frames and prefinished birch ply, I could place holes exactly where I wanted—even near edges—without the bit walking. The black oxide finish also sheds resin reasonably well, though it’s not a miracle coating; I still give it a quick wipe after hitting knotty pine.

Cutting performance is brisk in softwood and controlled in hardwood. The 11/64 twist clears chips well at moderate RPMs. I ran it mostly between 1,000–1,500 RPM in hardwood and a little faster in softwood. Backing the bit out once mid-drill kept flutes from clogging in MDF and melamine.

Countersink quality

The four-flute, multi-cutter countersink is the story here. It leaves a smooth chamfer with minimal chatter. In maple and oak, the surface was impressively clean—no ragged fibers around the rim. In knotty pine, I saw a touch of fuzz at the edges on a few holes, which a quick pass with 220-grit or a countersink touch-up cleaned up.

About that 60-degree spec: most flat-head wood screws are closer to 82–90 degrees. On paper, that mismatch could be a concern. In practice, the multi-cutter profile produces a broad, neat seat that let standard #8 flat heads sit flush and look tidy on cabinet boxes and utility shelving. If you’re building exposed architectural millwork where the screw head chamfer must perfectly match an 82-degree profile, choose a bit set to your exact screw angle. For everything else—including hidden fasteners and paint-grade assemblies—the finish from this bit is absolutely serviceable and often excellent.

Accuracy and repeatability

With the split point and hex shank, I didn’t notice wobble or out-of-round holes. The bit tracks straight, and when paired with a depth collar I could repeat the same countersink depth across a dozen face frames without fiddling. That consistency is what makes flip-drive setups efficient, and this bit doesn’t get in the way.

Durability and maintenance

The cutting edges held up well through a small kitchen’s worth of cabinet boxes (birch ply) and a laundry build-out in MDF. Black oxide isn’t as hard-wearing as TiN or cobalt coatings, but in wood it’s fine, and it resists surface rust. If you accidentally clip a hidden brad or screw, expect to kiss some life goodbye on the countersink cutters—true of any multi-flute countersink. The nice part is you’re replacing just this component, not the whole assembly, which keeps costs sensible.

A few care tips that helped:
- Clear chips every hole or two in resinous woods to keep heat down.
- Run it at moderate RPM and let the cutters do the work—pushing hard just polishes the edges.
- A drop of light oil on the countersink can reduce squeal in very dry hardwoods.

Materials and limits

This is a wood-first bit. It did fine in:
- Softwood framing and pine shelving
- Birch and maple plywood
- Poplar and oak face frames
- MDF and melamine (with routine chip clearing)

I would not use it in metal, composites with abrasive fillers, or cementitious panels. If you need a tapered pilot and countersink for hardwood joinery, look at tapered systems with stop collars; this straight 11/64 is tuned for clearance.

Ergonomics and workflow

The hex shank makes quick changes truly quick. On a pocket-hole cabinet build, I ran a rhythm: drill clearance and countersink with this, flip to driver, set the screw, move on. Not having to swap tools or bits speeds up the work and reduces mistakes. The overall stubby length helps in corners, but if you need deep counterbores, the reach won’t be there.

What could be better

• Angle specificity: If you’re matching a visible 82-degree screw head chamfer, you may want a dedicated countersink set to that angle.
• Bit size flexibility: 11/64 is correct for #8 clearance, but I’d love a modular option to swap to smaller pilots when I know I’m going into dense hardwood and want more thread engagement in the top piece.
• No depth stop included: That’s expected for a replacement component, but plan to reuse your collar or pick one up.

Value

The value proposition is straightforward: replace the wearing part, keep the flip-drive body. The bit’s performance in wood is consistently good, the countersink finish is smooth, and the split point reduces the little annoyances (walking, tear-out) that slow you down. With a 30-day money-back guarantee, there’s low risk to try it and see if it fits your workflow.

Tips for best results

• Mark and start at moderate speed; let the split point bite before committing.
• Use a depth collar for uniform countersink depth across a run of holes.
• Back out mid-hole in MDF or melamine to evacuate dust and avoid heat.
• If you’re joining hardwood to hardwood, consider predrilling a separate pilot in the lower board.

Bottom line

As a replacement part for a flip-drive setup, the DeWalt #8 countersink bit does exactly what I want: clean clearance holes, tidy countersinks, and fast, reliable work in a range of common woods. It’s not a one-bit solution for every joinery scenario, and the countersink angle won’t satisfy purists on exposed, angle-matched hardware. But for cabinetry, shelving, shop fixtures, and general trim where speed and consistency matter more than a perfect 82-degree chamfer, it’s a dependable, cost-effective choice.

Recommendation: I recommend this bit if you routinely drive #8 flat-head screws in wood and you use a flip-drive or quick-change setup. It’s quick, clean, and economical to maintain. If your work demands exact-angle, show-surface countersinking or tapered pilots in dense hardwoods, look to a more specialized countersink system instead.