Plane (tool)

A plane is a tool for shaping wood. Planes are used to flatten, reduce the thickness of, and impart a smooth surface to a rough piece of lumber. Special types of planes are designed to cut joints or decorative mouldings.

Though most planes are pushed across a piece of wood, holding it with one or both hands, Japanese planes are pulled toward the body, not pushed away. A cutter which extends below the bottom surface, or sole, of the plane slices off shavings of wood. A large, flat sole on a plane guides the cutter to remove only the highest parts of an imperfect surface, until, after several passes, the surface is flat and smooth.

Roman planes found at Pompeii are largely similar to planes in use today.

Parts of a Plane

Two styles of plane are shown with some parts labeled:

• A: The Mouth is an opening in the bottom of the plane down through which the blade extends, and up through which wood shavings pass.
• B: The Iron is a plate of steel with a sharpened edge which cuts the wood.
• C: The Lever cap holds the blade down firmly to the body of the plane.
• D: The Depth adjustment knob controls how far the blade extends through the mouth.
• E: The Knob is a handle on the front of the plane.
• F: The Chipbreaker or Cap iron serves to make the blade more rigid and to curl and break apart wood shavings as they pass through the mouth.
• G: The Lateral adjustment lever is used to adjust the iron so that the depth of cut is uniform across the mouth.
• H: The Tote is a handle on the rear of the plane.

Types of Planes

Planes are sometimes categorized as bench planes or block planes. Bench planes are characterized by a cutting iron bedded with the bevel facing down, attached to a chipbreaker. Block planes are characterized by a cutting iron bedded with the bevel up, and the absence of a chipbreaker. On the top in the image is a bench plane; on the bottom is a block plane.

Bench planes are sometimes named according to their length:

• A smoothing plane is up to 10 inches (250 mm) long.
• A jack plane is around 14 inches (350 mm) long.
• A fore plane is around 18 inches (450 mm) long.
• A jointer plane is around 22 inches (550 mm) long.

Planes may also be classified by the material of which they are constructed:

• A wooden plane is entirely wood except for the blade. The iron is held into the plane with a wooden wedge, and is adjusted by striking the plane with a hammer.
• A transitional plane has a wooden body with a metal casting set in it to hold and adjust the blade.
• A metal plane is largely constructed of metal, except, perhaps, for the handles. The planes in the image are metal planes.
• An infill plane has a body of metal filled with wood on which the blade rests.

Some special types of planes include:

• The shoulder plane, which trims tenons and other joints.
• The rabbet plane, also known as a rebate or openside plane, which cuts rabbets (shoulders, or steps) and dadoes.
• The router plane, which cuts grooves and shallow mortises.
• The scrub plane, which removes large amounts of wood quickly.
• The chisel plane, which removes wood up to a perpendicular surface such as from the bottom inside of a box.

Planing With the Grain

Planing wood generally results in splintering just ahead of the cutting tool. Whether this splintering occurs harmlessly above the cutting surface or unattractively below the cutting surface is largely a matter of cutting with the grain or against the grain, respectively. The grain referred to in these phrases is the side grain of the piece of wood being worked.

When planing with the grain, the inevitable splinters ahead of the cutting tool rise above the cutting surface, rather than below. These splinters are shaved off when the cutting tool reaches them, leaving a relatively smooth surface.

Planing Against the Grain

When planing against the grain, the inevitable splinters ahead of the cutting tool originate below the cutting surface, resulting in a jagged finish.

Note that these diagrams and phrases apply to planing the wide face (flat grain) and/or long side (side grain) of a typical piece of lumber, which is cut so its wide face is along the grain. In other words, as part of the tree, the wide face was parallel to the pith and thus along (or parallel to) the direction of the dominant cells, or grain. Because of the nature of wood, planing the end grain of the board is physically different than planing the wide face or the long side.

See also

• spokeshave

References

• Hack, Garrett (1997) The Handplane Book. ISBN 1-56158-155-0
• Watson, Aldren A. (1982) Hand Tools: Their Ways and Workings. ISBN 1-55821-224-8
• Hoadley, R. Bruce. (2000) Understanding Wood: A Craftsman’s Guide to Wood Technology. ISBN 1-56158-358-8
• Salaman, R. A. (1989) Dictionary of woodworking Tools. ISBN 0-04-440256-2

See also: Plane (tool), Block plane, Hand plane, Jointer plane, Lumber, Pith, Pompeii, Rabbet plane, Scrub plane