Choosing Jigsaw Blades
Blade selection makes a big difference in the performance and cut quality of any jigsaw. Follow these tips for selecting the right blade for any job.
Is it T or U for you?
First, consider how the blade mounts in your saw. In older jigsaws—and some current bargain-priced tools—a setscrew secures a U-shaped (universal) blade tang [Photo A, below]. Most newer jigsaws use T-shaped tangs that slide in and lock in place, no tools required. Some saws accept both types.
Metal shows its mettle
Manufacturers produce blades in four primary metal compositions for slicing through all types of material [Photo B, below], so consider what you'll cut.
Choose high-carbon steel (HCS) blades for cutting wood, MDF, or plastic. Though it may dull quicker, this softer, less expensive steel has more flexibility, making it well suited for scroll cutting.
High-speed steel (HSS) blades excel at cutting nonferrous metal, as well as acrylics. They have a more durable cutting edge than HCS blades, but additional rigidity can lead to more blade breaks.
Select bimetal (BIM) blades for cutting wood, metal, and laminates. These blades combine the flexibility of HCS with the durability of HSS, making them less likely to break. Though more costly, they will typically outlast both HCS and HSS blades.
For really tough jobs, such as cutting through embedded nails or metal, use a blade with tungsten-carbide-edged teeth. Toothless blades with tungsten-carbide grit on the edge cut glass, concrete board, brick, and tile.
The truth about the teeth
The number of teeth per inch (tpi) determines the speed at which the blade cuts efficiently [Photo C, above]. A lower tpi cuts aggressively, leaving a rougher edge [Photo D, below]; blades with 10–24 tpi produce markedly smoother cuts but at a slower pace.
Teeth bend to alternating sides to cut a wider kerf, helping remove waste, and reduce binding and heat buildup.
The set of the blade's teeth can also impact cut quality, and manufacturers set them in one of two ways.
Milled teeth have a pronounced tooth set [Blade Teeth Anatomy, below] created by pressing each tooth shape from a blade blank. This set helps the blade cut faster, and the wider kerf reduces blade wear. As a result, milled teeth last longer in dense material. However, the set leaves a rougher cut surface.
Ground teeth have no set. Grinding produces sharper edges, but because the teeth align with the blade body, these blades cut slower and hotter. Ground teeth produce a smoother cutline.
No matter the material, there's likely a jigsaw blade designed specifically for cutting it [Photo E, below].
Knife-edge blades cut soft materials, such as leather, cork, and foam insulation sheets. Flush-cut blades, if your saw accommodates them, allow cutting right up to the leading edge of the jigsaw's foot plate. Diamond-grit blades cut through tough materials such as glass, granite, slate, and more. The downward-pointing teeth of a reverse-tooth blade cut on the downstroke, resulting in a splinter-free cut on the top face of veneered plywood and laminates.