A saw is a tool for cutting wood or other material, consisting of a serrated blade (a blade with the cutting edge dentated or toothed) and worked either by hand or by steam, water, electric or other power. The teeth of the saw are each bent to specific angle and this angle is called "set". The set of a tooth is dependent on the kind of cut the saw will be making. For example a "rip saw" has a tooth set that is similar to the angle used on a chisel. The idea is to have the teeth rip or tear the material apart.
Some saws, such as the abrasive saw, use an abrasive disc or band for cutting, rather than a serrated blade.
The saw can also be used, more uncommonly, for playing music.
According to Chinese tradition, the saw was invented by Lu Ban. In Greek mythology, Perdix, the nephew of Daedalos, invented the saw. In reality, metal saws likely evolved from Neolithic stone tools.
* Heel: The end closest to the handle.
* Toe: The end farthest from the handle.
* Front: The side with the teeth (the "bottom edge").
* Back: Opposite the front ("top edge").
* Teeth: Small sharp points along the cutting side of the saw.
* Gullet: Valley between the points of the teeth
* Fleam: The angle of the faces of the teeth relative to a line perpendicular to the face of the saw.
* Rake: 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)
* Points per inch (25 mm): The most common measurement of the frequency of teeth on a saw blade. This is measured by setting the tip, or point, of one tooth at the zero point on a ruler, and then counting how many points are contained within one inch (25 mm) of length, counting inclusively. There will always be one more point per inch than there are teeth per inch (e.g., a saw with 14 points per inch will have 13 teeth per inch, a saw with 10 points per inch will have 9 teeth per inch). Some saws do not have the same number of teeth per inch throughout their entire length, but the vast majority do.
* Teeth Per inch : Another common measurement of the amount of teeth residing in any one inch length of a saw blade. Usually abbreviated as TPI, eg a blade consisting of 18TPI (Teeth Per Inch).
* Kerf: Width of the saw cut. On most saws the kerf is wider than the saw blade because the teeth are flared out sideways (set). This allows the blade to move through the cut easily without getting stuck (binding). However, some saws are made so that the teeth have no set on one side. This is done so that the saw can lie flat on a surface and cut along the surface without scratching it. These are referred to as flush cutting saws.
A saw is a tool for cutting wood or other material,
Cuuting tools , Machinery tools SEAGAMES 2009 at 4:29 AM
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