Set
The term “set” refers to the way in which the saw teeth are bent or positioned. Bending the teeth creates a kerf that is wider than the back of the blade.
Set patterns are usually selected depending upon the type of material that needs to be cut. Three common set patterns are shown in Figure 37.
Generally, the Raker set is used for cutting |
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metal workpieces; the Wave set, when the |
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thickness of the workpiece changes, such as |
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cutting hollow tubing or structurals. The Straight |
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set is most often preferred when cutting wood or | Figure 37 |
plastics. |
Material
Band saw blades can be made from different types of materials. Some of the most common include spring steel, carbon steel, bimetal (carbon 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 28.
Blade Breakage
Band saw blades are subject to high stresses and breakage may sometimes be unavoidable. However, many factors can be controlled to help prevent most blade breakage. Here are some common causes for breakage:
1. Misalignment of the blade guides.
2. Feeding workpiece too quickly.
3. Using a wide blade to cut a tight radius curve.
4. Excessive tension.
5. Teeth are dull or improperly set.
6. Upper guides are set too high off the workpiece.
7. Faulty weld on blade.
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