Fig. 5.
The back saw is used almost exclusively for making tenons, and has uniformly fine teeth so as to give a smooth finish to the wood.
Planes.—The plane may be called the æsthetic tool in the carpenter's kit. It is the most difficult tool to handle and the most satisfactory when thoroughly mastered. How to care for and handle it will be referred to in a subsequent chapter. We are now concerned with its uses only. Each complete kit must have three distinct planes, namely, the jack plane, which is for taking off the rough saw print surface of the board. The short smoothing plane, which is designed to even up the inequalities made by the jack plane; and the long finishing plane, or fore plane, which is intended to straighten the edges of boards or of finished surfaces.
Fig. 6. Jack plane bit
The Jack Plane.—This plane has the cutting edge of its blade ground so it is slightly curved (Fig. 6), because, as the bit must be driven out so it will take a deep bite into the rough surface of the wood, the curved cutting edge prevents the corner edges of the bit from digging into the planed surface.
On the other hand, the bits of the smoothing and finishing planes are ground straight across their cutting edges. In the foregoing we have not enumerated the different special planes, designed to make beads, rabbets, tongues and grooves, but each type is fully illustrated, so that an idea may be obtained of their characteristics. (Fig. 6a).