Chapter 21 Processes Used to Separate Wood Materials

Objectives Edged tools Planers and surfacers Lathes Sawing Drills and boring machines

Introduction There are 9 major types of processes used in manufacturing wood products: planing, jointing, shaping, routing, turning, sawing, drilling, boring, and mortising and tenoning.

Planing Planing or surfacing is a process that mills wood to a uniform thickness and produces a smooth surface. There are 3 major types of machines used for planing: knife blade planer, abrasive belt planer, and jointer. The jointer is the preferred machine from removing stock from the edges of boards. The abrasive bed planer is a safer machine than the knife bed planer. They are used in furniture manufacturing. They have heavy sanding belts.

Shaping Shaper is used for producing intricate shapes required for molding or window framing. Shapers produce straight line or design patterns along the length of the stock. Often special purpose wooden guides or fences are fastened to the shaper table.

Routing The router is used to add simple round or decorative shapes to the corners of stock, tables, and counter tops. Routers are popular in the furniture making and boat building industries. CNC routers are often used when a number of identical parts are required.

Turning Turning on a wood lathe is removing stock using a lathe tool called a chisel. Chisels come in six different shapes: gouge, skew, parting tool, diamond point, round nose, and square nose tool (fig 21-13, page 313). Initial turning operation is called roughing. It is done at low speeds of 1000 rpm or less.

Sawing Saw cuts made across the grain are referred to as crosscut sawing. Cuts made in the direction of the grain are referred to as rip sawing. Circular saw blades are used for most of the machine powered saws: portable circular saws, radial arm saws, cutofff saws and panel saws.

Drilling Machine drilling, or boring, of holes in wood is normally done with a drill press or a boring machine. The tools that are used to produce holes are called (drill) bits. To ensure accurate and safe operation, the work piece is held securely in a fixture bolted to the table of the drill press.

Boring In the furniture making industry, holes are often bored for inserting dowels (wooden connecting pegs) in parts such as drawers or shelves. Multi spindle boring machines (enables more than one hole to be bored at a time) are normally available in sizes of up to 6 feet long. There may be as many as 20 spindles on large production machines.

Mortising and Tenoning Mortise and tenon joints, with one piece chiseled to fit into a slot cut into a slot in another, are the mark of fine furniture (fig , page 319). Most furniture joints are secured with screws, dowels, or biscuits (flat discs). Screws provide the weakest joint, and dowels create a loose joint through expansion and contraction.

Summary There are 9 major types of processes used in manufacturing wood products: planing, jointing, shaping, routing, turning, sawing, drilling, boring, and mortising and tenoning. Planing or surfacing is a process that mills wood to a uniform thickness and produces a smooth surface. Shaper is used for producing intricate shapes required for molding or window framing. Machine drilling, or boring, of holes in wood is normally done with a drill press or a boring machine. Mortise and tenon joints, with one piece chiseled to fit into a slot cut into a slot in another, are the mark of fine furniture.

Home Work 1. What is planing? 2. What is a shaper used for? 3. What are mortise and tenon joints?