Woodworking plans use a lot of specialist words, and a few clear definitions make them much easier to follow. This glossary covers the wood itself, the cuts you make and the joints that hold pieces together. Where a term varies between makers or regions, check your plan or manual.
About the Wood
- Grain: the direction of the wood fibers. Cutting with or across it behaves differently.
- Hardwood and softwood: groups of wood based on the type of tree, not always on how hard the wood feels.
- Plywood: a sheet made of thin layers glued together with grain turned at angles.
- Board foot: a unit of lumber volume used by some sellers.
- Figure: the visual pattern in a piece of wood.
Cuts and Shapes
- Crosscut: a cut across the grain.
- Rip cut: a cut along the grain.
- Dado: a slot cut across the grain, where another piece can sit.
- Rabbet: a step cut along an edge or end.
- Chamfer: an angled edge that removes a sharp corner.
- Kerf: the slot a blade leaves behind.
Joints and Fixing
- Butt joint: two pieces simply meeting end to face.
- Miter joint: two angled ends joined to form a corner.
- Dovetail: interlocking shapes often used in drawers.
- Mortise and tenon: a slot and a matching peg shape.
- Pocket hole: an angled hole used to drive a screw into another piece.
Finishing Terms
| Word | Meaning |
|---|---|
| Grit | The coarseness of sanding material |
| Sealer | A coat that prepares wood for later coats |
| Stain | A coloring product that soaks into wood |
| Topcoat | The final protective layer |
How the Words Fit Together
Plans often chain these terms into one instruction. For example, a plan might ask you to rip a board to width, crosscut it to length, cut a rabbet along one edge and join it to another piece with a butt joint and screws. Read each step slowly, and picture the board with its grain running along its length.
It helps to sketch the piece and label each cut with the term the plan uses. If two plans use different names for the same cut, trust the drawing over the word.
- Check which face of the board is shown in each drawing.
- Note the direction of the grain on the plan.
- Mark waste areas so you cut on the correct side of the line.
Lumber Sizing and Surface Terms
Buying wood introduces a vocabulary that can be confusing at first. Dimensional lumber is sold under a nominal size, and the actual size is usually smaller after drying and planing, so check the stated dimensions in the listing or ask the seller. Rough-sawn describes boards with a coarse surface left from the saw, while surfaced or planed boards have been smoothed. S4S means surfaced on four sides, and it indicates a board ready for easier use, while S2S has two faces smoothed.
Thickness is often described in fractions of an inch or in quarters, and some sellers use a quarter system in which a given number indicates thickness before milling. Check with your supplier what their notation means. Width and length are usually given as stated or random, and board feet, as noted earlier, are a volume unit used by some sellers.
Moisture content refers to how much water the wood contains. Kiln-dried boards have been dried in controlled conditions, while air-dried boards have dried naturally. Wood that is too wet for your project can shrink or distort as it dries, so ask about moisture and allow time for acclimation.
- Nominal size: the trade name of a size, which is not the actual measurement.
- S4S: surfaced on four sides.
- Rough-sawn: left with the saw’s texture.
- Kiln-dried: dried in a controlled chamber to a lower moisture level.
Wood Movement and Defect Terms
Wood changes with moisture, and several terms describe the results. Cupping is a curve across the width of a board, bowing is a curve along its length on the face, and crook is a curve along the edge. Twist, also called winding, is a spiral distortion where corners no longer lie in one plane. Checks and splits are cracks, usually along the grain, which can appear as wood dries or is stressed.
Knots are the bases of branches, and they may be tight or loose. Pitch pockets hold resin in some softwoods. Sapwood is the lighter outer wood of a tree and heartwood is the darker inner wood, and they may differ in color and sometimes in durability. Tear-out and burn are surface defects caused during machining.
Understanding these terms helps you inspect boards before buying. Sight along each board to see if it is straight, check the ends for cracks and look for unsound knots. Choose boards that suit the use, and set aside the best sections for visible parts. Plan to cut around defects where you can.
- Cupping: a curve across the board’s width.
- Bowing: a curve along the length of the face.
- Twist: a spiral warp of the board.
- Check: a crack that follows the grain.
Hand Tool and Machine Terms for Wood
Many terms describe how tools are used on wood. To joint a board means to create a flat, straight edge or face, and to plane means to remove thin shavings to smooth or thickness a board. A jointer and a thickness planer are machines that do these tasks, and each has safety instructions that should be read in the manual. A bench plane is a hand tool for flattening and smoothing. A chisel removes small amounts of waste for fitting joints, and a mallet taps it. A marking gauge scribes a line parallel to an edge.
A table saw and a miter saw are power tools for straight and angled cuts, and a band saw handles curves and resawing, which means cutting a board along its thickness to make thinner pieces. A router shapes edges and cuts grooves, and a jig is a guide that helps repeat a cut or hold a workpiece. A fence is an adjustable guide on a machine, and a stop block limits the length of a cut.
Push stick and push block are safety aids that keep hands away from blades. Featherboards press the workpiece against a fence. Follow the maker’s manual for correct use, and learn the safe procedure for each machine before attempting a cut.
- Resaw: to cut a board through its thickness.
- Jig: a guide that holds or repeats a cut.
- Fence: an adjustable guide on a machine.
- Push stick: a safety aid that keeps hands clear of the blade.
More Joinery and Assembly Terms
Beyond the basic joints, plans use words for parts and assembly steps. A tenon is the projecting part that fits into a mortise, and shoulders are the flat areas around it. Cheeks are the broad sides of a tenon. A tongue and groove joint has a projecting tongue that fits into a slot, often used in flooring and paneling. A lap joint overlaps two pieces, and a half-lap removes half the thickness of each so they sit flush. Biscuits and dowels are small inserts that help align and reinforce joints.
Assembly vocabulary includes dry fit, which means testing the parts together without glue, and glue-up, the process of applying glue and clamping. A caul is a straight board used to spread clamp pressure. Squeeze-out is the glue pushed from a joint. Racking is when a frame distorts out of square, and a diagonal measurement helps check it.
Some plan terms describe the project’s parts. Rails are horizontal members and stiles are vertical members of a frame. A panel is a flat piece set into a frame. A carcase or case is the box structure of a cabinet, and a face frame is a framework attached to the front. A back is the rear panel, and a shelf pin supports an adjustable shelf.
- Dry fit: testing parts together without glue.
- Rails and stiles: horizontal and vertical frame parts.
- Racking: distortion of a frame out of square.
- Carcase: the box structure of a cabinet.
Finishing and Sanding Terms in Detail
Finishing has its own language, and understanding it helps you follow product labels. Oil finishes soak into wood and cure within the fibers, while film finishes such as varnish and lacquer build a protective layer on the surface. Wax is a soft protective coating, often applied over other finishes. Dye and pigment stains differ in how they color wood, and a wood conditioner may be used on blotch-prone species before staining. Check each product label for compatibility between layers.
Sanding terms include grit progression, which describes moving from coarse to fine abrasives, and raising the grain, which happens when moisture makes fibers stand up and feel rough, so a light sanding is often done after the first wipe of water-based product. Scratch pattern refers to visible marks left by coarser grits, and it can show through finishes. Sanding sealer is a product that makes subsequent sanding easier.
Application words include brushing, wiping and spraying, each of which suits different products. Drying time, recoat time and cure time are listed on labels and are not the same thing. Ventilation and protective gear are required for many finishes, so read the safety sections and dispose of rags and leftovers as the label directs.
- Grit progression: moving from coarser to finer abrasives.
- Raising the grain: fibers standing up after moisture contact.
- Film finish: a coating that builds a layer on the surface.
- Recoat time: the window for applying another coat.
FAQ
Why do plans use both rip and crosscut?
Wood behaves differently along and across the grain, so the choice of blade and technique often changes. Your plan or saw manual will guide you.
Is a miter the same as a bevel?
No. A miter is usually an angle across the width of a board, while a bevel is an angle through its thickness.
Why is a two-by-four not actually two inches by four inches?
Nominal sizes are trade names, and the finished board is smaller after drying and planing. Check the stated actual dimensions on the listing or ask the supplier.
What is the difference between hardwood and softwood in practice?
The terms refer to the kind of tree, not always to how hard the wood feels. Individual species vary, so check supplier information for the properties you need.
What is a board foot?
It is a unit of volume used by some lumber sellers. Ask the seller how they calculate it, since measurement conventions can differ.
What does it mean to dry-fit a project?
It means assembling the parts without glue to check the fit and plan the clamping. It helps you spot problems before the glue starts to set.
What is resawing?
It is cutting a board through its thickness to produce thinner boards. It is usually done on a band saw, and the manual explains safe setup and techniques.
What causes cupping in boards?
Uneven moisture changes between the two faces cause the board to curve across its width. Storing boards flat with air circulation and finishing both faces helps reduce it.
What is the difference between rails and stiles?
Rails are the horizontal members of a frame, while stiles are the vertical ones. Plans use both terms for doors and panel frames.
The Short Version
Knowing grain, cuts and joint names makes plans far easier to read. Keep this list nearby, and follow the maker’s manual for any tool you use to make these cuts.