Backsaw
Encyclopedia
Hand saw
In woodworking and carpentry, hand saws, also known as "panel saws", "fish saws", are used to cut pieces of wood into different shapes. This is usually done in order to join the pieces together and create a wooden object. They usually operate by having a series of sharp points of some substance...
which has a stiffening rib on the edge opposite the cutting edge, allowing for better control and more precise cutting than with other types of saws. Backsaws are normally used in woodworking
Woodworking
Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...
for precise work, such as cutting dovetails
Dovetail joint
A dovetail joint or simply dovetail is a joint technique most commonly used in woodworking joinery. Noted for its resistance to being pulled apart , the dovetail joint is commonly used to join the sides of a drawer to the front....
, mitres
Miter joint
A miter joint , sometimes shortened to miter, is a joint made by bevelling each of two parts to be joined, usually at a 45° angle, to form a corner, usually a 90° angle...
, or tenons
Mortise and tenon
The mortise and tenon joint has been used for thousands of years by woodworkers around the world to join pieces of wood, mainly when the adjoining pieces connect at an angle of 90°. In its basic form it is both simple and strong. Although there are many joint variations, the basic mortise and tenon...
in cabinetry
Cabinet making
Cabinet making is the practice of using various woodworking skills to create cabinets, shelving and furniture.Cabinet making involves techniques such as creating appropriate joints, dados, bevels, chamfers and shelving systems, the use of finishing tools such as routers to create decorative...
and joinery
Joinery
Joinery may refer to:* Woodworking joints or other types of mechanical joints * The work of the joiner, the fabrication and installation of fittings in buildings with materials such as wood and aluminum * In Australia and New Zealand, a joinery is also the generic term for a business which...
. Because of the stiffening rib, the backsaws are limited in the depth to which they can cut. Backsaws usually have relatively closely spaced teeth, often with little or no set.
Types of backsaw
Backsaws include the tenon saw, the dovetail saw, the (United Kingdom) sash saw1 and the gent's saw. Tenon and dovetail saws usually have a pistol gripPistol grip
On a firearm or other tool, the pistol grip is that portion of the mechanism that is held by the hand and orients the hand in a forward, vertical orientation, similar to the position one would take with a conventional pistol such as the M1911....
style handle which may be open or closed at the bottom. The gent's saw has a thin turned
Woodturning
Woodturning is a form of woodworking that is used to create wooden objects on a lathe . Woodturning differs from most other forms of woodworking in that the wood is moving while a stationary tool is used to cut and shape it...
handle which is parallel to the blade. Some dovetail saws also have this style of handle.
Different types of backsaw include:
- Mitre sawMiter sawA miter saw is a saw used to make accurate crosscuts and miters in a workpiece.-Manual miter saw:The basic miter saw is the manual miter saw. It is a saw suspended on rollers in a metal guide that works with a miter box that allows making accurate crosscuts and miter cuts...
— often referred to a large backsaw (20-30 inches or 60-90 cm) used either in a wooden mitre boxMitre boxA mitre box is a woodworking tool used to guide a hand saw to make precise mitre cuts in a board.The most common form of a mitre box is a 3-sided box which is open at the top and the ends. The box is made wide enough to accommodate the width of the boards to be cut. Slots are cut in the walls of...
or in a metal frame which allowed cutting mitres of any specified angle. Note that not all mitre saws are backsaws, and the electric mitre saw (or chop saw) has taken its place today. - Tenon saw, or often just backsaw — a midsized backsaw used to cut tenons or in a mitre box. The saw derives its name from its use in the cutting of tenons for mortise and tenon joinery. Tenon saws are commonly available with rip-filed teeth for rip cutting and cross-cut for cutting across the grain. Teeth are relatively fine, with 13 teeth per inch being a common size for the saw.
- Sash saw — name that seems to have been used in the 18th and 19th century for a smaller tenon saw, used in fabricating window sashes. The term is also used currently to refer to a thin, flexible saw used to free sashes that have been painted shut.
- Dovetail saw — a small backsaw used to cut dovetails. Although most dovetail saw teeth are set for cross-cuttingCrosscut sawA crosscut saw is a saw that is specially designed for making crosscuts. A crosscut is a cut made horizontally through the trunk of a standing tree, but the term also applies to cutting free lumber...
, a rip sawRip sawIn woodworking, a cut made parallel to the direction of the grain of the workpiece is known as a rip cut. If one were to cut a tree trunk in half from top to bottom, this would be a rip cut — but the term also applies to cutting free lumber....
tooth pattern is more efficient. These saws will usually have a higher number of teeth per inch (around 15 T.P.I.) with teeth sharpened to favor ripping operations and set to leave a narrow kerf. - Gent's saw or Gentleman's saw (rare) — a small dovetail saw with a straight turned handle, rather than an open one typical of most saws. The name seems to have arisen from its use by the nineteenth century dilettante who would now be called a hobbyHobbyA hobby is a regular activity or interest that is undertaken for pleasure, typically done during one's leisure time.- Etymology :A hobby horse is a wooden or wickerwork toy made to be ridden just like a real horse...
ist but it is hard to find a nineteenth century reference to it. For example, in the section on tools in Every Man his own Mechanic (1881) (816pp), tenon, dovetail and sash saws are listed as a group but there is no mention of a gent's saw. It is adapted for use in making joints in very small woodwork such as that in some musical instrumentMusical instrumentA musical instrument is a device created or adapted for the purpose of making musical sounds. In principle, any object that produces sound can serve as a musical instrument—it is through purpose that the object becomes a musical instrument. The history of musical instruments dates back to the...
s, dolls' furnitureDollA doll is a model of a human being, often used as a toy for children. Dolls have traditionally been used in magic and religious rituals throughout the world, and traditional dolls made of materials like clay and wood are found in the Americas, Asia, Africa and Europe. The earliest documented dolls...
or other model-makingScale modelA scale model is a physical model, a representation or copy of an object that is larger or smaller than the actual size of the object, which seeks to maintain the relative proportions of the physical size of the original object. Very often the scale model is used as a guide to making the object in...
. Its distinguishing features are its small size and turned handle. - Razor saw — A very small backsaw having very finely pitched crosscutCrosscut sawA crosscut saw is a saw that is specially designed for making crosscuts. A crosscut is a cut made horizontally through the trunk of a standing tree, but the term also applies to cutting free lumber...
teeth, often with no set. The Razor saw is used by hobbyists, notably Model aircraftModel aircraftModel aircraft are flying or non-flying models of existing or imaginary aircraft using a variety of materials including plastic, diecast metal, polystyrene, balsa wood, foam and fibreglass...
, Model boatModel yachtingModel yachting is the pastime of building and racing model yachts. It has always been customary for ship-builders to make a miniature model of the vessel under construction, which is in every respect a copy of the original on a small scale, whether steamship or sailing ship...
, and Model railroadRail transport modellingRailway modelling or model railroading is a hobby in which rail transport systems are modelled at a reduced scale...
enthusiasts. Razor saws typically use disposable blades (or are occasionally designed to be completely disposable), since their teeth are so small as to be impractical to re-sharpen. A razor saw is capable of making clean cuts in very soft woods like BalsaBalsaOchroma pyramidale, commonly known as the balsa tree , is a species of flowering plant in the mallow family, Malvaceae. It is a large, fast-growing tree that can grow up to tall. It is the source of balsa wood, a very lightweight material with many uses...
, which most other saws would tend to tear out. Unlike most other types of backsaws, razor saws are also frequently used to cut plastics and soft metals. - Dōzuki — a Japanese backsawJapanese sawThe Japanese saw or ' is a type of saw used in woodworking and Japanese carpentry that cuts on the pull stroke, unlike the European saw that cuts on the push stroke. This allows it to have thinner blades that cut more efficiently and leave a narrower cut width...
, used for centuries by carpenters and cabinetmakers in Japan. Although this saw does not share an ancestry with the other backsaws in this group, the concept is the same. Like most Japanese saws, the dōzuki cuts on the pull stroke, allowing for much straighter and narrower cuts than those achieved with push-stroke saws. This is due to tension on the blade during the cut (versus compression for a western saw), so less thickness is required to keep the saw blade straight.
The design
The work of a backsaw requires a thin, stiff blade. These two immediately incompatible requirements are resolved by swagingSwage
Swaging is a forging process in which the dimensions of an item are altered using a die or dies, into which the item is forced. Swaging is usually a cold working process; however, it is sometimes done as a hot working process....
(and perhaps, spot welding
Spot welding
Spot welding is a process in which contacting metal surfaces are joined by the heat obtained from resistance to electric current flow. Work-pieces are held together under pressure exerted by electrodes. Typically the sheets are in the thickness range...
) a stiffening cap over the length of the top edge of the blade. This thickening of the blade is the back and is generally made from some kind of metal, usually brass or steel. The stiffening back is carried through into the handle so that the blade does not bend between the two. The thickening of the back limits the depth to which the saw can cut but this is generally not a limitation in their typical uses.
Associated tools
- A backsaw is often used in combination with a mitre box to produce angled cuts.
- Another accessory commonly used is the bench hookBench hookA bench hook is a workbench accessory used in woodworking. The purpose of the bench hook is to provide a stop against which a piece of wood being worked can be placed to hold it steady whilst cutting, planing, or chiseling that piece of wood....
. - Another tool associated with the use of backsaws is the marking knife. This leaves a cleaner line than a pencil would and it cuts the fibres at the surface of the wood. Without this, the action of the saw would lift them and leave a ragged edge.
Footnote
- Note 1: In North America, the name sash saw is used for a frame sawFrame sawFrame saw sometimes refers to a woodworker's bow saw.A frame saw is a type of rip saw. It consists of a relatively narrow and flexible blade held under tension within a rectangular frame...
used in sawmillSawmillA sawmill is a facility where logs are cut into boards.-Sawmill process:A sawmill's basic operation is much like those of hundreds of years ago; a log enters on one end and dimensional lumber exits on the other end....
ing.