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Jigsaw blades are application tools for jigsaws. Their properties determine largely their usefulness for specific jobs, the quality of the cut and the work progress.

The properties of jigsaw blades are determined by the following criteria:

- tooth geometry
- shank and tooth material
- shank shape

Tooth geometry

Every material to be cut has its own density. For sawing this means that a precisely matched cutting geometry is needed to achieve the best possible cutting quality and the fastest work progress. Jigsaw blades and saw blades for reciprocating saws must be optimised with regard to tooth spacing, i.e. the distance between two teeth, tooth shape and cutting angle, and finally the type of offset, i.e. side set, wavy set or taper ground versions.

Teeth milled, side set
Blade for medium rough cuts and quick work progress in hard- and softwood, aluminium, synthetic materials and non-ferrous heavy metal.

Teeth milled, wavy set
Blade for fine, straight cuts in plywood, low carbon (soft) steel, aluminium, non-ferrous heavy metal and synthetic materials.

Teeth ground, side set
Blade for clean, quick cuts in wood or plastic.

Teeth ground, taper ground set
Blade with tapered backing; for precise, fine and neat cuts in wood and plastic.


Tooth spacing
The tooth spacing, i.e. the distance from one tooth to the next, is chosen according to the thickness of the material to be cut. The rule of thumb is that at least two teeth should be in the material at the same time. If less than two full teeth are imbedded in the material, the cut will become rough and full of vibrations, with high mechanical strain on the machine. More than two teeth in the material ensure quieter cutting, in thicker materials this might be at the expense of work progress. You should always select the blade with the widest possible tooth spacing for the workpiece.

Progressive tooth spacing, i. e. narrow spacing near the plug-in side and progressively larger spacing towards the tip, ensures both excellent work progress and quality of the cut for stock of standard thickness.

Vario toothing, a succession of teeth with smaller and larger tooth spacing distributed over the length of reciprocating saw blades, has become widely accepted for metal cutting due to quiet running and excellent work progress.


Blade width
The width of the saw blade is crucial for two features: directional stability and curving ability. The wider the blade, the better the guidance for straight cuts, the narrower the blade, the worse the guidance for straight cuts. In special curve-cutting blades the line where the teeth start is set back so far that it is in extension of the lifter rod axis. With these saw blades, you can almost turn round "on the spot". Their reduced width makes curve-cutting blades more sensitive. They should only be used for their intended purpose.


Saw blade thickness
The thickness of the saw blade affects the precision of straight cuts and the work progress. With thick saw blades all stroke-type saws guided with one hand (jigsaws, sabre saws) produce more accurate straight and angled cuts. Therefore you should use thicker blades to improve the accuracy of cuts. A disadvantage of thick saw blades is their rather slow work progress, because the thicker blade has to reduce more material to chips and sawdust than a thinner blade.


Saw blade material
The material of the blades, and especially their teeth, are chosen to suit the processed material. A general rule is that the teeth have to be harder than the processed material. However, with increasing hardness saw blades become brittle and can fracture, whereas elastic saw blades become blunt rather quickly. For special applications saw blades with flexible body and hard teeth are best suited. These can be so-called bimetal blades or saw blades with TC teeth or TC coating. The higher price for these blades is more than compensated by their longer service life, even during "normal" use.

HCS
Carbon steel for use in softer materials like wood, fibre board and plastic.

HSS
Fully hardened high speed steel for use in harder materials like metal, aluminium and non-ferrous metal.

Bimetal
The highly flexible and unbreakable connection between HSS and HCS meets the highest demands in cases where shanks may break or flexible blades are required. The life of BOSCH bimetal jigsaw and sabre saw blades is two to ten times longer than pure HSS or HCS solutions which gives an excellent price/value ratio. Their application ranges from wood, steel and non-ferrous metal to aluminium. Depending on blade width they are used for narrow curve cutting, all-purpose cutting with above average strain, or quick and accurate straight cuts.

TC coated
The HCS carrier is coated with a layer of TC grains. Their application is recommended for abrasive materials like tiles, glass, cast iron and bricks.

TC tipped (single tooth)
The HCS carrier is equipped with TC teeth and is recommended for abrasive materials like reinforced plastics, asbestos cement, hard wood and gas concrete.

TC tipped (tooth rail)
The HCS carrier is equipped with a TC rail. In this version Bosch offers a range of special blades for stainless steel and soft steel.


Shank fittings
Individual power tool manufacturers around the world equip their jigsaws with different blade fittings. However, it is likely that in the long-term the BOSCH single lug shank will become the standard jigsaw blade fitting. As the worldwide largest manufacturer of jigsaw blades BOSCH provides jigsaw blades with all available shanks.


Special saw blades
Special saw blades with unique geometry were developed to be suitable for special materials (blades for cardboard, rubber, leather, carpet and polystyrene), stainless steel blades for sabre saws, plunge and straight saw blades for the in-line grip jigsaw, files and rasps for jigsaws and reciprocating saws.


Pocket cut and straight saw blades for multisaws
An innovative multi-purpose saw blade for quick and clean pocket cuts without pre-drilling in wood with a thickness of up to 40 mm.