Every alternate tooth, 1st.

3d, 5th, etc., is filed, and then the saw is reversed and the other set, the 2nd, 4th, 6th, etc., is filed.
[Illustration: Fig.97.A Saw-Jointer.] [Illustration: Fig.98.

Saw-Set.] In filing a rip-saw the file should move exactly perpendicularly to the plane of the saw blade, that is, directly across the teeth.

The filing is done on the back of the teeth, the file just touching the face of the next one.

The filing is continued, with one, two, or three strokes, for each tooth, as the case may require, or just until each tooth is sharp.
In filing a crosscut-saw, the file is held pointing upward and toward the point of the saw.