WMH Tool Group JET JWBS-18X, Инструкция по эксплуатации и каталог запасных частей

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Width
Band saw blades come in different standard
widths, measured from the back of the blade to
the tip of the tooth. Generally, wider blades are
used for ripping or making straight cuts;
narrower blades are often used when the part
being cut has curves with small radii. (When
cutting straight lines with a narrow blade, the
blade may have a tendency to wander, causing
"blade lead".)
Pitch
Pitch is measured in "teeth per inch" (TPI).
Figure 23 shows blades with different pitches. A
fine pitch (more teeth per inch) will cut slower
but smoother. A coarse pitch (fewer teeth per
inch) will cut rougher but faster. As a rule of
thumb, the thicker the workpiece, the coarser
will be the blade pitch. If you have to cut a hard
or very brittle material, you will probably want to
use a blade with a finer pitch in order to get
good clean cuts.
General rule: Use a blade that will have no
fewer than 6 and no more than 12 teeth in the
workpiece at any given time.
Shape
Figure 24 shows common types of tooth shape.
Tooth shape has an effect on cutting rate, and
with few exceptions, the Skip and Hook types
are used to obtain higher feed rates when
cutting thick workpieces. Variable-tooth blades
are also available, which combine features of
the other styles.
Set
The term "set" refers to the way in which the
saw teeth are bent or positioned. Set patterns
are usually selected depending on the type of
material that needs to be cut. Three common set
patterns are shown in Fig. 25.
Generally, the Raker set is used for cutting
metal workpieces; the Wave set, when the
thickness of the workpiece changes, such as
cutting hollow tubing or structurals. The Straight
set is most often preferred when cutting wood or
plastics.
Material
Band saw blades can be made from different
types of materials. Some of the most common
include spring steel, carbon steel, carbon steel
equipped with a high speed or welded edge (bi-
metal), or carbide tips. A special type of saw
blade is made from "high speed steel"; these
should not be used on band saws with low rates
of speed.
Figure 23
Figure 24
Figure 25