Drill Joinery

These proven methods yield joints ranging from purely practical to fun and fancy without sacrificing strength.
WOOD Magazine Staff January 25, 2021
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Screws reinforce butt joints better than almost any other form of joinery. A right-angle brace keeps the workpieces at a 90u00b0 angle.

Screws: As simple as it gets

How it works
Drill pilot holes fully through one workpiece and partially into the mating workpiece, then connect the two with screws.

  • Pros
  • Easy and quick
  • Costs only pennies per screw
  • Vast choices of readily available screw types and sizes
  • Pair with dadoes, grooves, or rabbets for almost foolproof joint alignment
  • Exterioruse coated screws available
  • Wood plugs can be used to conceal screwheads.
  • Cons
  • Visible screwheads can detract from a project's appeal.
  • Lack of a pilot hole, or one that's too small, can cause the screw to split the wood
  • Read reviews of countersinking bits and other drilling accessories. woodmagazine.com/drillbits
A countersinking bit (top) creates perfect pilot holes for flathead wood screws, with a countersink for the screwhead. Drill a little deeper to create a counterbore to accommodate a screw-hiding wood plug.

Pocket screws: A (mostly) hidden connection

How it works
Clamp a jig with angled guides to the workpiece, and use a stepped drill bit to bore a counterbored pilot hole with a shoulder for the panhead screw to rest against. Then connect the two pieces with screws.

  • Pros
  • Easy and quick
  • The pockets can be concealed (typically on the least visible surfaces of the project).
  • Multiple sizes of drill guides and screws readily available
  • Exterioruse coated screws available
  • Cons
  • Requires a jig costing from $20 to $225
  • If visible, pockets can detract from a project's appeal.
A pocket-hole jig guides the bit to create angled pilot holes. The best jigs either hold the workpiece or clamp to it for drilling.
A cutaway view of a pocket hole shows the angle the screw takes into the mating workpiece. The shoulder stops the panhead screw at the proper depth.

Dowels: Seen or unseen, they require great precision

How it works
Drill mating holes in workpieces, typically using a jig to guide the bit, then glue in wood dowels of the same diameter.

  • Pros|
  • Precut short dowels and dowel rods are readily available in birch and poplar in common fractional diameters; other species are available, typically through woodworkingspecific retailers.
  • Dowels can be hidden for a fastenerfree look, or exposed on their ends as a design element.
  • Jigs, especially selfcentering models can help you achieve consistently precise spacing across each workpiece's thickness.
  • Cons
  • Precise alignment of mating holes is critical; even slightly misaligned holes will mess up a joint.
  • Requires a jig, costing from $20 to $250
This self-centering doweling jig locates precisely positioned dowel holes and can drill holes of four different diameters.
A single-sided doweling jig locates holes a fixed distance from a workpiece edge. This works great, providing you reference all holes from the same surfaces.
With a tap from a mallet, dowel centers mark the centerpoints for drilling holes in the mating workpiece.

Mortise and tenon: Tried and true for centuries

How it works
Form a mortise in one workpiece by drilling overlapping holes and chiseling the mortise square. Then, with a tablesaw, bandsaw, or hand tools, you cut a matching tenon on the other piece.

  • Pros
  • Considered the strongest joint in woodworking
  • ​* Using a doweling jig ensures alignment of overlapping holes to create precise mortises.
  • Uses common twist or bradpoint drill bits you already own
  • Should you mistakenly make a mortise oversize, you can size the tenon to fit.
  • You can also make loose tenons—which fit into mortises on both workpieces—by routing roundovers along both edges of stock. This way, you can leave the mortise ends round.
  • Cons
  • Requires skill gained through practice
  • After drilling the holes, you still need to clean up the mortise with a chisel.
A good mortise-and-tenon joint should fit together snugly with hand pressure, yet come apart with moderate pulling force prior to gluing.
Drill out a mortise with a series of overlapping holes made with a doweling jig.
Flatten and smooth the mortise walls with a chisel. Take care to hold the chisel 90° to the workpiece to ensure a mortise with square walls.
Loose-tenon joints function similarly, but with a short length of tenon that fits into mortises on both mating workpieces.

Miller dowels: An easy, can't-miss fit

How it works
A multi-tiered bit drills a stepped hole through mating workpieces that perfectly fits these unique dowels.

  • Pros
  • You don't need a guide to drill the holes.
  • Dowels come in three sizes and are available in birch, oak, cherry, and walnut.
  • Easy to use: Drill the hole, add glue, and tap in the dowel.
  • You can highlight the exposed dowel end as a design feature, especially when using contrasting wood species.
  • Cons
  • A starter kit, with a bit and 50 or 100 dowels, costs $25 to $35.
  • Additional dowels cost 19¢–43¢ apiece.
  • If you wobble the drill while drilling, the oversize hole will not tightly fit the dowel.
Secure workpieces with a right-angle brace before drilling with the Miller bit. Hold the drill at 90° to ensure holes are centered on the mating workpiece.
Here's a stepped Miller dowel ready to be driven home in its matching hole. During assembly, seat the dowel as deep as it will go, then trim the end flush.
A finished Miller dowel joint, crafted with the stepped bit and walnut dowels (oak dowels also shown).

Beadlock®: A no-chisel mortise-and-tenon method

How it works
Use a jig to drill overlapping holes to form mortises in mating workpieces. Then glue in a tenon formed with the matching profile.

  • Pros
  • Easy to do—just like drilling dowel joints
  • More gluing surface than a typical loose mortiseand-tenon joint makes it stronger.
  • Concealed joints improve a project's appearance.
  • You can purchase a router bit ($52) to make your own tenons.
  • Cons
  • Requires a kit costing from $30 to $130
  • Birch tenon stock costs $9–$10 for packs of 15–25, depending on thickness.
  • Precise alignment of mating mortises is critical; even slightly misaligned mortises will mess up a joint.
Drill the Beadlock mortise with a series of overlapping holes using the jig and included bit. Repeat for the mating workpiece.
Beadlock tenons look like stacked dowels, but are routed from a solid piece of wood. They fit perfectly into mortises of the same shape.
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