Technical Information
Band SawsBlade Basics (continued)
Tooth Set
Raker Set
These are individually set teeth — first right then left —
followed by an unset tooth. The unset tooth (raker tooth)
allows for fast chip removal and a straight cutting actions
This tooth set is recommended for general purpose cutting
applications.
Wavy Set
Wavy set teeth are set in groups, right and left, in varying
degrees. Wavy set teeth are recommended for cutting light
metal sections, such as sheet, tubing, and small solid shapes.
Alternate Set
In an alternate tooth set, every tooth is set — one left,
one right — throughout the blade length. This tooth set is
primarily used for cutting wood.
Variable Set
Variable set teeth are set in alternating groups with a single
unset tooth (raker tooth). When these are combined with the
varying set angles of the teeth, a faster, smoother, quieter
cutting actions is achieved. Variable tooth blades perform
extremely well on most applications and provide fast cutting
on solids, shapes, structural, and piping.
Wavy SetRaker SetAlternate SetVariable Set
Successful Band Saw
Operation and GeometriesGuidelines
21° R12° R7-1/4° R5-7/16° R3-3/4° R2-1/2° R1-7/16° R5/8° R5/16° RInchmm1-1/21-1/413/45/81/23/81/43/163832252016131065Width of Band SawMinimum Radii Cut Chart
Blade Width Selection
The dimension from tooth tip to back edge of the blade is the
blade width. The greater the width, the greater the resistance
to deflection while cutting. For straight cutting applications,
use the widest blade the machine can accept. For contour
cutting use the widest blade that the contour radius will
permit, see Minimum Radii Cutting Chart to the right.
Radii in this chart are based on manual feeding of one-inch
thick milled steel. To cut close tolerance radii the following
factors must be considered:
• Blade width • Material thickness
• Machinability • Feed force
• Location of pivot point
Teeth Per Inch
The pitch of the blade is defined by the number of TPI (Teeth
Per Inch). Non-ferrous materials such as brass, bronze, and
aluminum require a large chip area. A low TPI, or "course"
pitch, prevents the chips from clogging and binding together
in the gullets, which can diminish sawing and damage the
blade.
On thin walled pipe, tubing, and sheet, many teeth per inch
are required in order to avoid damaging or breaking the teeth.
A low TPI blade is the best blade for cutting large cross-
sections. The ability of each tooth to cut into the workpiece
is increased because the saw's feed pressure is distributed
over fewer teeth. A coarse pitch blade increases productivity
and provides large chip clearing gullets.
Blade Break-In
Set Band Saw machine at the recommended speed for the
material to be cut. When cutting easily machined metals, the
cutting rate should be set at 1/3 to 1/2 of the recommended
rate for the first 50 to 75 square inches.
When cutting difficult to machine metals, such as tool steels
or workhardened alloys, set the cutting rate at 3/4 of the
recommended rate for the first 25 square inches. Gradually
increase the feed until you achieve the recommended
cutting rate after 50 to 60 square inches.
continued on the next page