Chainsaw
A chainsaw (or chain saw) is a portable mechanical saw, typically powered by a two-stroke engine. It is used for cutting trees, to fell snags, to cut firebreaks in wild land fires, and to harvest firewood. Special chainsaws are used for cutting concrete.
Parts
A chainsaw has several parts, including:
- Engine — usually a two-stroke gasoline (petrol) internal combustion engine, usually with a cylinder volume of 30 to 120 cubic centimetres (0.030 to 0.120 l) or electric motor.
- Drive mechanism — typically a clutch and sprocket.
- Guide bar — a long bar with a round end of wear-resistant alloy steel usually 16 to 36 inches (41 to 91 cm) in length. An edge slot guides the cutting chain.
- Cutting chain — Usually each segment in this chain (which is constructed from riveted metal sections similar to a bicycle chain, but without rollers) features small sharp blades called teeth. The bottom of each link features a small metal finger called a "drive link" which locates the chain on the bar, helps to carry lubrication oil around the bar, and engages with the engine's drive sprocket inside the body of the saw.
As chainsaw carving has become more popular, the makers of chainsaws are making special short, narrow-tipped bars for carving. These are called "quarter tipped," "nickel tipped" or "dime tipped" bars, based on the size of the round tip. After sometime the chainsaw chain gets dull.
Chainsaw Media
Historical osteotome, a medical bone chainsaw
McCulloch Electric Chainsaw. Photo by Eric Bear Albrecht, 2004. Placed in the public domain by the photographer as of September 29, 2005.
A chainsaw in use in Tokyo to cut branches
A cordless 4 inch chainsaw commonly known as a "Ripper"
The cutting chain seen here features the popular chipper-teeth style of cutting blades.
Close up of the centrifugal clutch on a chainsaw
Author's work
Chainsaws can be modified to suit different use-cases. Pictured is a hedge trimmer attachment fixed to a chainsaw bar, with teeth that catch hedge branches.