Tooth Patterns

There are a lot of different tooth patterns for band saw blades, but the three most com

Gentle Curves: I cut gentle curves wide and sand to the line, so a smoothfinish isn t needed. A Vf-wide skip tooth blade ivith U tpi works well. The small number of teeth and wide gullets lets me cut quickly.

mon are standard (or raker), skip tooth, and hook tooth blades, see the examples at left and drawings below. Each one is used for making a different type of cut. The difference between them is the cutting angle of the teeth (the rake), and the amount of space between the teeth (the gullet).

standard blade. Standard tooth blades are usually narrower (Vi6n to VV'-wide) and have the most teeth per inch. They're evenly spaced so the teeth and gullets are the same size.

The cutting angle on the standard blade is 0°. This means the teeth are 90° to the back of the blade, so they don't really cut the wood — they actually scrape it instead. This allows the smoothest cut of the three patterns, but you have to feed the workpiece slow and steady into a standard tooth blade.

skip tooth blade. The skip tooth blade has a 0° cutting angle just like the standard blade. But the skip tooth blade only has half the number of teeth as the same size standard blade Gt's missing every other tooth). This increases the size of the gullets so the skip tooth can cut a little faster than the standard blade. Of course, the end result is not quite as smooth.

hook tooth blade. The teeth on the hook tooth point down a little (usually at 5-10°). So they cut the wood — not just scrape it. And because it cuts more aggressively and needs to hold more sawdust, the hook tooth blade also has larger rounded gullets.

Resawing: Resawing wood into thin stock creates a lot of resistance. A 1/2*-wide blade won Yflex or bend easily. And a hook tooth pattern with «? teeth per inch (tpi) will clear out the waste quickly.

Stroll-type Cuts: For tight circles, I use a W standard blade with lb tpi. It can cut a circle with a Va' radius, and it leaves a nice, smooth surface. But narrow blades need more support, refer to next page.

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