Joinery
Woodworking Joints and Joinery
A page for each joint: what it is, where it is the right choice, how to size it, and which machine or hand tool cuts it. Dovetails, mortise and tenon, rabbets, dadoes, box joints, half laps, bridles, splines, dowels, pocket holes, biscuits and loose tenons all get the same treatment, and the layout calculators do the arithmetic for your stock.
Geometry is exact, so it is shown as math. Sizes for joinery systems such as loose tenons, biscuits and pocket screws come from the makers of those systems. Proportions that are tradition rather than measurement, such as a tenon's thickness against the stock or the slope of a dovetail, are labelled as a traditional rule and name the references that state them, so you can always tell a measured number from a shop habit.
Calculators
- Dovetail calculatorLay out dovetails for any board: tail and pin widths on both faces, marks from the edge, and the slope as a ratio or an angle (1:6, 1:8).
- Box joint calculatorFinger joint spacing that fits your board: how many fingers a dado stack or bit gives, the leftover, and the even width for an adjustable jig.
- Mortise and tenon calculatorTenon thickness for your stock by the one-third rule, rounded to a mortise chisel you can buy, with the shoulder on each cheek. Inches or mm.
Reference
- Dovetail angle chartDovetail ratios from 1:4 to 1:10 in degrees, the traditional 1:6 softwood and 1:8 hardwood slopes, and router bit angles as ratios.
- Pocket screw length chartKreg pocket screw length for each board thickness from 1/2 to 1 1/2 in, the jig setting, and fine vs coarse thread, from Kreg’s own manual.
- Biscuit size chartLamello biscuit sizes #0, #10, #20 and H9 in mm and inches, with the cutting depth for each size on Lamello’s joiner.
- Domino size chartEvery Festool Domino tenon size, which machine cuts it, the routing depth and the mortise widths, from Festool’s manual and catalogue.
- Dowel size chartDowel pin diameters and lengths sold by three makers, and the dowel size for your stock by the one-third rule, labelled as tradition.
- Pocket hole joineryHow pocket-hole joints work, how to set the jig and drill collar, which screw length and thread to use, and joining two thicknesses.
- Biscuit jointWhat a biscuit joint is, how a plate joiner cuts the slot, the biscuit sizes and depths, and what the joint is for.
- Festool DominoHow the Festool Domino cuts loose-tenon joints: tenon sizes, routing depth, hole widths for alignment, and the DF 500 vs DF 700.
- Dowel jointWhat a dowel joint is, why it holds where a glued end-grain butt joint fails, dowel diameter by stock thickness, and the sizes sold.
- Dovetail jointWhat a dovetail joint is, through vs half-blind vs sliding, the traditional 1:6 and 1:8 slopes, and how dovetails are cut by hand or with a jig.
- Through dovetailHow to lay out and cut a through dovetail: baselines, half pins, spacing the tails, the slope across the thickness, and fitting the joint.
- Half-blind dovetailThe half-blind (single-lap) dovetail for drawer fronts: the lap, socket depth, tail layout and slope, and cutting it by hand or with a router jig.
- Sliding dovetailHow a sliding dovetail joins a shelf or rail across a board, and how to cut the groove and the tongue with one dovetail bit.
- Mortise and tenonWhat a mortise and tenon is, why it holds where end grain meets edge grain, the one-third tenon rule, its variations and the tools that cut it.
- Tongue and grooveWhat a tongue and groove joint is, glued panels vs floating boards, and how to cut it with matched router bits or on the table saw.
- Rabbet jointWhat a rabbet is, how deep to cut one (no more than 1/2 in in 3/4 in stock, by tradition), and how to cut it with a router, table saw or plane.
- Dado jointDado vs groove, how deep a dado should be, sizing a dado for real plywood thickness, stopped dados, and cutting them on a saw or router.
- Finger jointWhat a box (finger) joint is, how to space the fingers evenly across a board, and how to cut them with a jig on the table saw or router table.
- Half lap jointWhat a half lap joint is, the geometry (half the thickness from each piece), and how to cut it with a dado stack, a router or by hand.
- Bridle jointWhat a bridle (open mortise) joint is, the traditional proportions, how to cut it on the table saw, band saw or by hand, and how it compares.
- Spline jointWhat a spline is, why a mitre needs one, hidden vs key splines, grain direction and fit, and how the slots are cut.
Other sections
- WoodSpecies and wood types: hardness, weight, movement, color and what each is good for.
- FinishingFinishes, glues and fillers: dry and cure times, which to use, and how they compare.
- Lumber & plywoodBoard feet, actual and nominal sizes, hardwood quarters, plywood sizes and grades.
- Tools & machinesSetup and choice for the table saw, miter saw, router, planer, jointer, lathe and CNC.
- Fasteners & drillingScrew sizes, pilot and clearance holes, countersinks and drill bit sizes.