M42 Band Saw Blade

Description

Choosing the proper thickness of the blade is important. Continual flexing and heating and cooling causes metal fatigue and ultimately, failure.

The thickness of the blade depends on the diameter of the wheels, and the work to be done. Thick blades withstand more cutting strain from straight cuts but can break more easily from the bending and twisting action. Thinner blades perform well for lighter work. The following chart shows ideal blade thickness for various wheel diameters.

We use the word “width” but really it comes down to two things: The maximum capacity your bandsaw can accommodate and the minimum radius you want to cut. Start by consulting the manufacturer’s instructions.

If you are doing re-sawing, cant or cut-off sawing, use your bandsaw’s maximum blade width. This will keep the cuts nice and straight and you’ll get a decent feed rate without breaking blades.

On the other end of the scale, if you do contour sawing, use a blade that is narrow enough to cut the desired radius. The chart below shows the correlation between blade width and the minimum radius it will cut.

If the blade is pressing hard on the side guides it may lead to poor quality cuts, but it will certainly lead to shortened blade life and shortened guide life. Having the guides press hard against the blade will cause the guide and blade to get very hot. Hot enough to distort the blade and wear out the side guide wheel or block. Also, having the blade rub hard on the guide is basically the same thing as asking the blade to wrap around a very small radius wheel and will cause the blade to break. The ideal blade setup is to wrap a dollar bill around the blade then adjust the guides in until they just touch the dollar bill, then take it out. This leaves a close but free running fit. In truth you can be more sloppy than this with acceptable gap ranging from just kissing to 1/32 inch. It is very important that the side guides never be both touching the blade at the same time, i.e. zero gap.

Once the blade guides are properly set up go back and do a quick recheck of the blade tracking on the wheels.

Wheel Diameter (Inches) Blade Thickness (Inches)

4 – 6 .014

6 – 8 .018

8 – 10 .020

11 – 18 .025

18 – 24 .032

24 – 30 .035

30+ .042, .050, .063

lade Width (Inches) Minimum Radius (Inches)

1/8 3/16

3/16 5/16

1/4 5/8

3/8 1-1/2

1/2 2-1/2

5/8 4

3/4 5-1/2

1 7

Pictures