What Are Wood Paddle Bits and What Are They Used For? | Spade Bits Explained

Wood paddle bits, also called spade bits, are flat blade-shaped drill bits that bore large, fast holes in wood for wiring, pipe, and bolts.

A paddle bit is a flat steel blade with a sharp center point and two cutting spurs on the outer edges. The point bites into the wood and stops the bit from wandering, while the spurs score the rim of the hole as the blade spins. Most models run on a 1/4-inch hex shank, so they fit standard drills and impact drivers that accept that interface. Allied Bolt describes the design as a “spade point” built for large circular holes in wood, and that is the whole idea: speed and hole size, not furniture-grade finish.

How Are Wood Paddle Bits Built?

Typical paddle bits are stamped from heat-treated high-carbon steel, with size markings often laser-engraved on the blade for quick identification. A representative 1/2-inch x 6-inch model lists a heat-treated high-carbon-steel body, a 1/4-inch hex shank, a 6-inch overall length, right-hand cutting direction, and a 0.500-inch (12.7 mm) cutting diameter. The same product line includes 3/4-inch and 7/8-inch versions at 19.05 mm and 22.225 mm.

Hilti’s WDB-S spade bit uses a 1/4-inch hexagonal connection end with a 100-mm working length, and Hilti specifies wood and wood composites as the base materials for that bit. Some specialized designs add a threaded self-feeding tip, wing tips, a cupped spade, or spur-and-reamer edges. Hilti states its WDB-S is intended for shallow holes in wood, including softwood and hardwood, and can be used overhead with SID impact tools.

What Are Wood Paddle Bits Used For?

Paddle bits are the go-to choice for rough or utility openings where a clean hole wall does not matter. Electricians use them to bore cable runs through studs, plumbers use them to open paths for pipe, and carpenters use them for clearance holes for bolts, screws, and threaded rod. Framing, remodeling, and general construction work all lean on them for the same reason: they cut fast and they cut big.

Softwood, hardwood, and wood composites all work, provided the bit and the tool suit the job. A few honest limits apply. Paddle bits are not meant for metal, masonry, glass, or tile unless a specific manufacturer expressly permits that material. They also are not precision woodworking tools — a brad-point bit, auger bit, or Forstner bit generally does better when the hole needs a clean entry, an exact diameter, a flat bottom, or minimal tear-out. And a hex shank alone does not guarantee impact rating; Hilti explicitly identifies impact-drilling capability for its WDB-S, while other product pages mainly describe standard drill and impact-driver fit.

Prices are retailer listings and will change, so treat the table as a rough yardstick. If you want a curated set comparison before you buy, see our tested roundup of the best wood paddle bits. Gap size and stock thickness drive the choice more than price does — the manufacturer pages reviewed do not give a universal maximum diameter or material limit, so check the individual model for its own spec.

How Do You Drill With A Paddle Bit?

Pick a bit whose diameter matches the opening you need and whose length reaches through the stock. Confirm the shank fits your tool, then mark the hole location and clamp or otherwise secure the workpiece — small pieces should never be held by hand. Place the center point on the mark and start at low speed so the point seats without walking. Build speed with controlled, straight pressure, and withdraw the bit periodically on deep holes to clear chips and cut heat.

When the point approaches the far face, ease off the pressure. A sacrificial backer board behind the workpiece reduces breakout, which is common when drilling all the way through lumber. Stop the tool completely before removing the bit or clearing chips, and wear eye protection throughout. Check for hidden wiring, plumbing, fasteners, and structural members before you drill anything. The reviewed manufacturer pages do not publish a single model-independent RPM chart, so follow your bit and drill manufacturer’s own speed guidance rather than a guessed number. One more field rule: never force a dull bit — excess pressure overheats it, stalls the tool, and can ruin the workpiece.