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Set
The term “set” refers to the way in whic h the saw
teeth are bent or positioned. Bending the teeth
creates a kerf that is wider than the back of the
blade. This helps the operator more easily pivot
a workpiece through curve cuts, and decreases
fr iction bet ween blade an d workpi ece on str aight
cuts.
Set patterns are usually selected depending
upon the type of material that needs to be cut.
Thr ee comm on set pat terns are shown i n Fi gure
57.
Figur e 57
Generally, the Raker set is used for cutting
metal workpieces; the Wavy set, when the
thickness of the workpiece changes, such as
cut ting hol l ow tubi ng or str uctur als. The Straight,
or Alternate, set is the one most used for
woodworking blades, and is also used to cut
plastics.
Material
Band saw blades can be made from different
types of metals. The most common include
spring steel, carbon steel, bimetal (alloy steel
equipped with a high speed cobalt steel edge
welded to it ), or carbide tips.
Because of the importance of blade selection, it
is recommended that you use the blade
selection guide on page 35. Also, listening to
experienced band saw users will provide
valuable information as to the types of blades
curr entl y on the market along wi th t heir pros and
cons.
Blade Breakage
Band saw blades are subject to high stresses
and breakage may sometimes be unavoidable.
Howev er, m any f ac tors can be cont rolled t o hel p
prevent most blade breakage. Here are some
common causes for br eak age:
1. Misalignment of the blade guides.
2. Feeding workpi ec e too quickl y .
3. Using a wide blade to cut a tight radius
curve.
4. Excessive tension.
5. Teeth are dull or im pr oper ly set .
6. Upper guides are set too high off the
workpiece.
7. Faulty weld on blade.
Although not essential, some users round or
“stone” the back edge of their blade. This is
done by pl aci ng a sharpeni ng stone on the t able
and in light contact with the back corners of the
blade as the blade is running. Rounding can
help the back blade edge move more smoothly
through the kerf, smooths the weld, and helps
prevent crack s fr om starti ng at the back c or ner s.