•Straight Cutting: Use the largest width blade that you own. Narrow blades can cut tight curves (a small radius) but are not very good at cutting straight lines because they naturally wander (blade lead). However, larg- er blades are much better at cutting straight lines, but function poorly at cutting small curves because of their size.
Tooth Style
When selecting blades, another option to con- sider is the shape, gullet size, teeth set and teeth
Raker Skip Hook
Figure 48. Raker, Skip & Hook tooth styles.
•Raker: This style is considered to be the standard because the tooth size and shape are the same as the tooth gullet. The teeth on raker blades usually are very numerous, have no angle, and produce cuts by scrap- ing the material; these characteristics result in very smooth cuts, but do not cut fast and generate more heat while cutting.
•Skip: This style is similar to a raker blade that is missing every other tooth. Because of the design, skip toothed blades have a much larger gullet than raker blades, and therefore, cut faster and generate more heat. However, these blades also leave a rougher cut than raker blades.
•Hook: The teeth on this style have a posi- tive angle (downward) which makes them dig into the material, and the gullets are usu- ally rounded for easier waste removal. These blades are excellent for the tough demands of resawing and ripping thick material.
Tooth Pitch
Usually measured as TPI (teeth per inch), tooth pitch determines the size of the teeth. More teeth per inch (fine pitch) will cut slower, but smoother; while fewer teeth per inch (coarse pitch) will cut rougher, but faster. As a general rule, choose blades that will have at least three teeth in the material at all times. Use fine pitched blades on harder woods and coarse pitched blades on softer woods.
Blade Care
A bandsaw blade is a delicate piece of steel that is subjected to tremendous strain. You can obtain longer use from a bandsaw blade if you give it fair treatment and always use the appropriate feed rate for your operation.
Be sure to select blades with the proper width, style, and pitch for each application. The wrong choice of blades will often produce unnecessary heat which will shorten the life of your blade.
A clean blade will perform much better than a dirty blade. Dirty or gummed up blades pass through the cutting material with much more resistance than clean blades. This extra resistance also causes unnecessary heat.
Blade Breakage
Many conditions may cause a bandsaw blade to break. Blade breakage is unavoidable, in some cases, since it is the natural result of the peculiar stresses that bandsaw blades are subjected to. Blade breakage is also due to avoidable circum- stances. Avoidable breakage is most often the result of poor care or judgement on the part of the operator when mounting or adjusting the blade or support guides.
G0636X 17" Ultimate Bandsaw |