It is very important to have the correct tooth pitch for the type of cutting that you are doing and the thickness of the material that you are cutting. The tooth pitch will also determine the finish produced, a coarse tooth pitch will leave a rougher finish with a faster cut while a fine tooth will produce a better finish but with a slower cut.
The general rule of thumb is to have at least 3 teeth in the cut at all times.
3tpi (teeth per inch) is used for fast cutting thick stock where the finish isn’t too important.
4tpi is again used for cutting thick stock, but with a better finish/slower cut and 4tpi won’t be able to cut stock as thick as a 3tpi blade.
6tpi and 10tpi are great general purpose tooth pitches that will cope with most materials leaving a decent finish.
14tpi and above are generally used for cutting thin stock, getting a fine finish or for cutting plastics, non ferrous metals etc.
Here is a chart to determine the minimum thickness material that a tooth pitch will cut:
Minimum Material Thickness It Can Cut
The SuperTuff Fastcut is 3tpi blade but with a smaller unset tooth in-between the cutting teeth that helps clear the debris and maintains a nice clean fast cut. The set on the teeth is kept to a minimum as it is designed for keeping waste to a minimum.
Some of the M42 blades are available in a vari-tooth format, for example the 1/2" x 6/10 Vari-Tooth blade will have sections of 6tpi and 10tpi on the same blade. The advantage of vari-tooth blades is that one blade is capable of coping with a wider variety of thicknesses and the vari-tooth design reduces blade resonance so they tend to give a better finish than a straight tpi blade.
When choosing the tooth pitch, please remember:
- Fewer teeth per inch will give a faster cut but with a rougher finish.
- More teeth per inch will give a smoother finish but slower cut.
- At least three teeth must be in the work piece at all times.