Size of the Band-Saw Blade

• The length of a band-saw blade is dictated by the size of the band saw and is often specified on the saw itself or in the instruction manual. The width of the blade can vary depending on the type of cutting to be done. Use wide blades for cutting large pieces of wood in a straight line. Use thinner blades for curved cuts. A 1-inch band-saw blade can cut a circle with a 7-inch radius, while a 1/4-inch blade can cut a circle with a 5/8-inch radius, according to AllBandSawBlades.com.
  
  

Teeth per Inch for Wood

• The higher the number of teeth per inch, the smoother the finish of the cut, according to RikonTools.com. A blade with a small number of teeth per inch will cut through the wood faster but can leave a rough edge to the cut. Generally, at least three teeth should be in the work piece during the cut. This means three teeth per inch is the minimum for cutting 1-inch-thick wood. Six teeth per inch is the minimum for cutting a ½-inch-thick piece of wood.
  
  

Blades for Metal or Plastic

• The blades with the highest number of teeth per inch are used for cutting thin plastics or metals. These blades often have between 18 and 32 teeth per inch, according RikonTools.com.
  
  

Blade Tension

• According to "Fine Woodworking" magazine, most saw blades require in excess of 15,000 lbs. per square inch to maintain a straight cut. Some blades (carbide-tipped or spring-steel for example) should be tensioned to nearly 30,000 psi. Confirm the proper tension by checking the manufacturer's information on the blade package. Check the actual blade tension on the tension scale of the saw or utilize a separate tension meter.
  
  

Blade Breakage

• A band-saw blade is a single piece of metal that can occasionally break. Some possible causes of this are defects in the weld at the joint of the blade, using a blade that is too wide for the saw or using too much force when pushing the material into the saw.