Jigsaw (tool)

A jigsaw is a reciprocating saw that can cut irregular curves, such as stenciled designs, in wood, metal, or other materials.

Jigsaws first emerged in the 19th century and employed a treadle to operate the blade, which was thin and under tension, being secured at both ends to an oscillating frame. This kind of saw is now usually called a scroll saw.

The modern portable jigsaw, with a rigid blade secured at one end and cutting on the up-stroke, was introduced in 1947 by Scintilla AG (later acquired by Bosch).

A jigsaw power tool is made up of an electric motor and a reciprocating saw blade. Jigsaws with sole plates that have a beveling function can cut angles typically up to 45 degrees relative to the normal vertical stroke to make miter joints. Portable jigsaws have historically been mains-powered, but are increasingly being displaced by battery-powered models.

The tool's ability to carve out irregular shapes lends its name to the jigsaw puzzle, whereby each tile is shaped to connect to its neighbors.

In 1946 Albert Kaufmann, an engineer of Scintilla AG company in Solothurn, Switzerland, replaced the needle on his wife's sewing machine with a saw blade. In 1947, after development of Kaufmann's invention, Scintilla started producing jigsaws under name "Lesto jigsaw". In 1954 Scintilla was acquired by Bosch. An important innovation by Scintilla-Bosch in 1966 was the "pendulum action", where the blade tilts forward in the upward (cutting) stroke, and back for the down-stroke, ejecting the chips, so the blade runs cooler and cuts faster. A significant model was the Bosch "LESTO 8 554" in which the degree of "pendulum action" could be selected to suit the material being cut. Such a mechanism introduces additional purchase and maintenance costs, and manufacture of such models may have ceased in recent years. Many modern jigsaws have an adjustment for tilting the blade tip forward, but at a static, fixed angle, claiming similar benefits.^{[citation needed]}

A jigsaw works by attaching a blade accessory to the tool. There are various types of blades in the market. Older jigsaws require a blade to be screwed into the tool. But since Bosch introduced the first tool-free blade change system, most manufacturers now offer a similar setup allowing a quick & tool-free blade change.^{[citation needed]}

There are T-shank blades and U-shank blades available in the accessory market. T-Shank blades are the industry-standard professional interface that provides a longer life and a tighter fit from the blade to the tool.^{[citation needed]}