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jig saw





jig saw
A hand-held power saw used for cutting curves, such as stenciled designs or other custom shapes, into a piece of wood or other material. A jig saw combines into a convenient package many of the functions of a band saw and a scroll saw. Jig saws are also called saber saws.

The essential parts of a jig saw are a reciprocating saw blade connected to an electric motor. Traditional jigsaws are hand saws, consisting of a handle attached to a small, thin blade.

Jigsaws come in 2 basic styles: D handled and barrel grip. They may also be corded or cordless. The cordless variety are handy in areas where extension cords are difficult to use. They're best suited to cutting wood and wood products. Although they can cut tougher materials, the extra power needed for these applications quickly drains batteries. Cordless jig saws are available from 12 to 18 volts – the higher the voltage, the longer the battery life. Corded jig saws are better able to handle tough cutting jobs or continuous use. They operate at from 3.5 to 6 amps. Higher amp motors give more power and enable the saw to cut thick boards, light metals, and other tough materials.

Before purchasing a jig saw, look to see if the mechanism for adjusting the base plate is sturdy. On less expensive models these are weak and will eventually wobble, making it difficult to cut accurately.


Features

  • Variable speed saws enable the speed of the blade to be adjusted according to the material being cut. When used in conjunction with properly matched blades, this feature provides cleaner, faster cuts in different materials. Variable speed saws typically have a range of 500 to 3,100 strokes per minute.

  • Orbital action moves the blade from side to side as well as up and down. This additional action enables the saw to cut through stock faster. Most orbital action saws have settings to change the amount of side-to-side motion based on the material being cut.

  • An adjustable foot or sole lets the operator make cuts at an angle to the face of the material. Most saws with this feature have a range of 0° to 45°.

  • Vacuum or blower features keep the cut line clear of sawdust and other debris during operation.

  • Tool-free blade changing lets the user change blades quickly and saves time when cutting multiple types of material.

  • Blade supports greatly reduce blade flexing during use. The reduced flexing leads to straighter cuts and extends blade life.

Jig saw blades

Jig saw blades are classified by width, number of teeth per inch (tpi), and material composition. The higher the tpi the smoother the cut; the lower the tpi the quicker the cut. Common types of blade include:
  • High speed steel (HSS). Usually used for wood and light metal cutting.

  • Bi-metal. Used for wood and light metal cutting.

  • Cobalt steel. Harder and longer-lasting than HSS or bi-metal blades. Commonly used for wood and metal cutting.

  • Carbide grit. Used to cut masonry board.

  • Scrolling. Narrower than typical jig saw blades and used to make tighter turning cuts.

Related category

   • TOOLS