In selecting a gauge the inexperienced are apt to select the more expensive styles, thinking they will be able to do better work with the higher priced tool. Taking every condition into account, the plain beechwood gauge (Fig. 151) with a boxwood screw and bar un-graduated is the best for the beginner as well as for the matured mechanic for most work. This gauge is light and strong, and as there is no brass on the face of the head, it is very easily planed smooth and straight when it wears uneven. It will keep in shape longer than some which have the brass facing. In no case should one depend upon the graduations upon the gauge-beam, but use the rule as explained in Lesson 3 (Use Of The Gauge).

Fig. 151. Plain Gauge.

In advanced work and for use in projects where many mortises of the same width are to be made, a mortising gauge may be used to good advantage. For all elementary work and for most other work the plain gauge is far better. The mortising gauge (Fig. 152) has two spurs on one side at one end so that the lines for both sides of a tenon or mortise may be drawn at the same time. There is also a single spur at the opposite side of the beam, that the gauge may be used for drawing a single line. The spur on all the gauges should be sharpened with a file to a sharp, flat, wedge-like point. The point should be a little rounded on the end, making the edge which is in front as the gauge is used a little the shorter. When properly sharpened and used it will make a neat, fine line. Fig. 153 indicates the shape of such a spur. The spur should extend at least an eighth of an inch from the lower surface of the bar, and for most work three-sixteenths of an inch is better. It should be out so far that the beam of the gauge will never be flat against the piece which is being lined.

Fig. 154. Pencil in Gauge Bar.

Fig. 153. Gauge Spur.

Fig. 152. Mortising Gauge.

It is sometimes convenient to have a lead pencil gauge line. This is easily accomplished by boring a hole through the gauge beam near one end and inserting the stub of a lead pencil. The pencil must have a very blunt point, as shown in Fig. 154.

When much thin lumber is to be worked, a splitting spur may be placed in the opposite end of the beam. Such a spur should split pine or basswood boards up to one-fourth inch in thickness. The spur may be made from the broken end of a knife blade as shown in Fig. 155. Before trying to split a piece, joint it carefully and then use the splitting gauge on both sides of the piece.

Fig. 155. Splitting Spur.