From Wikipedia, the free encyclopedia Saw
Saw
Saw
A crosscut hand saw about 620 mm (24 inches) long
Classification Cutting
Types Hand saw
Back saw
Bow saw
Circular saw
Reciprocating saw
Bandsaw
Related Milling cutter
A saw is a tool that uses a hard blade or wire with an
abrasive edge to cut through softer materials. The cut-
ting edge of a saw is either a serrated blade or an abra-
sive. A saw may be worked by hand, or powered by steam,
water, electricity or other power.
Terminology
• : The end closest to the handle.
• : The end farthest from the handle.
• : The side with the teeth (the "bottom edge").
• : Opposite the front ("top edge").
• : Small sharp points along the cutting side of the saw.
• : Valley between the points of the teeth
• : The angle of the faces of the teeth relative to a line
perpendicular to the face of the saw.
• : The angle of the front face of the tooth relative to a
line perpendicular to the length of the saw. Teeth
designed to cut with the grain (ripping) are generally
steeper than teeth designed to cut across the grain
(crosscutting)
• (25 mm): The most common measurement of the Diagram showing the teeth of a saw blade when looking front-
frequency of teeth on a saw blade. This is measured on. The teeth protrude to the left and right, so that the saw cut
by setting the tip, or point, of one tooth at the zero (kerf) is wider than the blade width. The term set describes
point on a ruler, and then counting how many points how much the teeth protrude.
are contained within one inch (25 mm) of length,
counting inclusively. There will always be one more Usually abbreviated as TPI, e.g. a blade consisting of
point per inch than there are teeth per inch (e.g., a 18TPI (Teeth Per Inch).
saw with 14 points per inch will have 13 teeth per • : Width of the saw cut. On most saws the kerf is wider
inch, a saw with 10 points per inch will have 9 teeth than the saw blade because the teeth are flared out
per inch). Some saws do not have the same number sideways (set). This allows the blade to move through
of teeth per inch throughout their entire length, but the cut easily without getting stuck (binding).
the vast majority do. However, some saws are made so that the teeth have
• : Another common measurement of the amount of no set on one side. This is done so that the saw can
teeth residing in any one inch length of a saw blade. lie flat on a surface and cut along the surface without
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From Wikipedia, the free encyclopedia Saw
scratching it. These are referred to as flush cutting Handmade manufacture
saws. Although the term kerf is often used to refer to
Until at least the mid-19th century, saws were made la-
the width of the saw blade, it actually means the
boriously by hand. Teeth were filed out individually, then
width of the cut, which is affected by the width of
"set" by striking alternate teeth with a hammer against a
the blade, the amount of wobble created during
"stake" or small anvil. Due to risk of breaking teeth, be-
cutting, and the amount of material pulled out of the
ginners were given saw set pliers which set even more
sides of the cut. This distinction can be important
slowly.[5]
because the use of a blade that is too thin can result
in excessive wobble and a wider kerf.
In a modern serrated saw, each tooth is bent to a precise
Saw pits
angle called its set The set of the teeth is determined by
set. Main articles: Saw pit and Two-man saw
the kind of cut the saw is intended to make. For example, In early English North America, the pit saw was one of
a rip saw has a tooth set that is similar to the angle used the principal industrial tools. It was a two-man saw, gen-
on a chisel. The idea is to have the teeth rip or tear the erally operated over a pit across which the logs to be cut
material apart. Some teeth are usually splayed slightly to into boards were mounted. The saw was "a strong steel
each side of the blade so that the cut width (kerf is wider
kerf) cutting-plate, of great breadth, with large teeth, highly
than the blade itself and the blade does not bind in the polished and thoroughly wrought, some eight or ten feet
cut. The kerf of the blade is adjusted with a tool called a in length"[6] with a handle on either end. The pit saw
saw tooth setter. took at least two men to operate. The "pitman" stood
An abrasive saw uses an abrasive disc or band for cut- in the pit— to raise the saw for the backstroke—and the
ting, rather than a serrated blade. "sawyer", standing above, guided the cut. Pit-saw work-
ers were among the best paid in early colonial North
America.
History The pit saw is also known as a whipsaw.[7]
Types of saws
Hand saws
Hand saw uses the blades thickness to remain stiff. The
pull stroke also reduces the amount of stiffness required.
Some examples are:
• Crosscut saw for making cuts perpendicular to the
grain
• Rip saw for cutting along the grain
Roman sawblades from Vindonissa approx. 3rd to 5th century • Two-man saw for cutting large logs or trees
AD
• Plywood saw fine-toothed blade to reduce tearing of
plywood
In ancient Egypt, saws made of copper are documented
• Veneer saw two edged saw with fine teeth used to
as early as the Early Dynastic Period, circa 3,000–2,800.[1]
cut veneer
Examples of saws and models of saws have been found in
• Hacksaw fine-toothed tempered blade under tension
many contexts throughout Egyptian history. Particularly
for cutting metal, bone, and other hard materials.
useful are tomb wall illustrations of carpenters at work
saw,
• Pad saw, keyhole saw jab saw narrow bladed saw.
that show sizes and the use of different types. Egyptian
• Fret saw for cutting intricate wood patterns
saws were set with the teeth projecting only on one side,
rather than in the modern fashion with the more advan- Back saws
tageous alternating set. Main articles: Backsaw and Japanese saw
According to Chinese tradition, the saw was invented The second category of hand saws utilize a thinner blade
by Lu Ban.[2] In Greek mythology, as recounted by by reinforcing it with a steel or brass back. Back saws are
Ovid,[3] Talos, the nephew of Daedalus, invented the saw. differentiated by the length of the blade. Some examples
In archeological reality, saws date back to prehistory and are:
most probably evolved from Neolithic stone or bone • Miter saw used to make accurate crosscuts and
tools. "[T]he identities of the ax, adz, chisel, and saw were miters in a workpiece
clearly established more than 4,000 years ago."[4] • Tenon saw also called a Dovetail saw or sash saw is
used in woodworking for precise work
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From Wikipedia, the free encyclopedia Saw
Mechanically powered saws • Sternal saw is used in surgery to open a patient’s
sternum.
Circular blade saws
Continuous band
• Circular saw, used in industrial sawing of log and
beams, typically found in sawmills – also name given • Band saw, with motor-driven continuous band
to smaller hand-held saws • Chainsaw, motor-driven, for felling trees
• Table saw, circular blade rising through a slot in a
table. A smaller direct-drive versions can be set on a Types of blades
workbench is called workbench saw. If set on steel
Blade teeth are of two general types: Tool steel or car-
legs it is called a Contractor’s Saw. A heavier version,
bide. Carbide is harder and holds a sharp edge much
which is more precise and more powerful and driven
longer.
by multiple belts with an enclosed base stand is
Band saw blade
called a Cabinet saw. A new version, called a hybrid
A long band with teeth on one side welded into a
saw, has the lighter weight mechanism of a
circle. Less waste than circular saws due to blade
Contractor saw but with an enclosed base like the
being thinner. More heat disapation because there
Cabinet saw.
is more blade to do the cutting. Usually run at a
• Radial arm saw is a versatile machine used mainly
slower speed than circular saw.
for cross-cutting. The blade is pulled on a guide arm
through a piece of wood held stationary on the saw’s Crosscut
table In woodworking, a cut made at (or near) a right
• Rotary saw is used to make accurate cuts without the
angle to the direction of the wood grain of the
need for a pilot hole in wallboard, plywood, and workpiece. A crosscut saw is used to make this type
other thin materials. It can be called a spiral cut saw of cut.
or a "RotoZip".
• Electric miter saw, (also called chop saw, cut-off saw Rip cut
or power miter box) is used for making accurate In woodworking, a cut made parallel to the
cross cuts and miter cuts. The basic model has its direction of the grain of the workpiece. A rip saw is
circular blade fixed at a 90° angle to the vertical, a used to make this type of cut.
compound miter saw’s blade can be adjusted to other
angles. A sliding compound miter saw has a blade Plytooth
which can be pulled through the work similar to the A circular saw blade with many small teeth
action of a radial arm saw, which gives a greater designed for cutting plywood with minimal
capacity for cutting wider workpieces. splintering.
• Concrete saw, usually powered by an internal
combustion engine and used with a Diamond Blade Dado blade
to cut concrete or asphalt pavement. A special type of circular saw blade used for
• Abrasive saw, which uses an abrasive disc for cutting making wide grooved cuts in wood so the edge of
rather than a toothed blade. Abrasive saws are used another piece of wood will fit into the groove to
for cutting very hard materials, such as metal. make a joint. Dado blades can make different width
grooves by addition or removal of chipper blades
Reciprocating blade saws of various widths between the outer dado blades.
• Jigsaw or saber saw (US) has a narrow blade for This first type is called a stacked dado blade. There
cutting irregular shapes. The term jigsaw was also is another type of dado blade capable of cutting
commonly used for what is now called a scroll saw. variable width grooves. An adjustable dado utilizes
• Reciprocating saw or sabre saw (UK and Australia) a movable locking cam mechanism which causes
use an action similar to a jigsaw. They are larger, the blade to wobble sideways more or less. This
more powerful and use a longer stroke with the allows continuously variable groove width from
blade parallel to the barrel. It is useful for demolition the lower to upper design limits of the dado.
work or for cutting pipe, and is sometimes powered
Strob Saw Blade
by compressed air.
A circular saw blade with special rakers/cutters to
• Scroll saw is a saw for making intricate curved cuts
easily saw through green or uncured wood which
(scrolls).
would otherwise jam the saw blade.
• Dragsaw is used for bucking logs before the advent of
the chainsaw.
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From Wikipedia, the free encyclopedia Saw
Materials used for saws • Chainsaw carving is a flourishing modern art form.
Special saws have been developed for this purpose.
There are several materials used in saws, with each of its • The production of Lumber, lengths of squared wood
own specifications. for use in construction, begins with the felling of
Brass trees and the transportation of the logs to a sawmill.
Mostly used in back saws because of its low price, Plainsawing: Lumber for structural uses is typically plain-
its flow characteristics that make the material sawn (also called flatsawn), a method of dividing the log
relatively easy to cast, and unlike other types of that produces the maximum yield of useful pieces and
saw, the forces that take place in back saws are therefore the greatest economy.
relatively low because of the pulling motion used. Quarter sawing: This sawing method produce edge-
grain or vertical gain lumber, in which annual growth
Steel rings run more consistently perpendicular to the pieces’
Used in almost every existing kind of saw. Because wider faces.
steel is cheap, easy to shape, and very strong, it has
the right properties for most kind of saws.
See also
Diamond
• Diamond tools
Fixed onto the saw blade’s base to form diamond
• Saw chain
saw blades. As diamond is a superhard material,
• Saw pit
diamond saw blades can be used to cut hard and
• Sawmill
brittle, or abrasive materials, for example, stone,
• Sawgrass (disambiguation)
concrete, asphalt, bricks, ceramics, glass,
• Sharpening
semiconductor and gem stone. There are many
• Two-man saw
methods to fix the diamonds onto the blades’ base
• Watersaw
and there are various diamond saw blades, which
are used in a variety of fields.[8]
References
High speed steel (HSS)
[1] Walter B. Emery Excavations at Saqqara, The Tomb of
The whole saw blade is made of High Speed Steel
Hemaka and Hor-Aha, Cairo, Government Press,
(HSS). HSS saw blades are mainly used to cut steel,
Bulâq, 1938 (2 vols)
copper, aluminum and other metal materials. If
[2] Lu Ban and The Invention of the Saw History
high-strength steels (e.g., stainless steel) are to be
Anecdote at Cultural China website
cut, the blades made of cobalt HSS (e.g. M35, M42)
[3] Ovid Metamorphoses Bk VIII:236-259: The death of Talos
should be used.[8]
A. S. Kline translation, Electronic Text Center at
Tungsten carbide University of Virginia Library
Normally, there are two ways to use tungsten [4] Richard S. Hartenberg, Joseph A. McGeough
carbide to make saw blades:[8] Neolithic Hand Tools at Encyclopaedia Britannica
Online
1. : The saw blade’s teeth are tipped (via welding) with [5] Tomlinson, C., ed. (1866). Tomlinson’s Cyclopaedia of
small pieces of sharp tungsten carbide block. This Useful Arts. London: Virtue & Co. Vol II, page 478.
type of blade is also called TCT (Tungsten Carbide [6] Charles W. Upham Salem Witchcraft with an account
Tipped) saw blade. Carbide tipped saw blades are of Salem Village and a History of Opinions on Witchcraft
widely used to cut wood, plywood, laminated board, and Kindred Subjects. Frederick Unger, New York,
plastic, grass, aluminum and some other metals. 1978 (Reprint), 2 vols., vol. 1, p 191
2. : The whole saw blade is made of tungsten carbide. [7] Glossary of Tools at (American) Pilgrim Hall
Comparing with HSS saw blades, solid carbide saw Museum website
blades have higher hardness under high [8] ^ Types of Saw Blades
temperatures, and are more durable, but they also
have a lower toughness.
External links
• Blade Terminology, Tooth Forms & Tooth Set
Uses • Selection of band saw blade advancements
• Saws are most commonly used for cutting hard • Saw Blade Tooth Shape
materials. They are used extensively in forestry, • Number of Teeth You Should Have on your Saw
construction, demolition, medicine, and hunting. Blade
• Musical saws are used as instruments to make music.
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From Wikipedia, the free encyclopedia Saw
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Categories:
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