Fig 74 Filing The Cutting Teeth Of A Timber

in the teeth, a rather blunt point is desirable. If the saw is to be used in soft wood, where strength of teeth is not so essential, a longer point may be filed. To obtain a long point, the handle end of the file is held low and to the right or left, depending on which side of the tooth is being filed. Full, light strokes of the file are most satisfactory for the work. Files cut on the forward stroke only, therefore the file is raised from the saw at each stroke. The point which is being filed needs to be watched closely at each stroke, to see that the point is brought over the center of the tooth and that the filing stops when the point has been reached.

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Setting the Teeth

The next step in fitting the saw is that of setting the teeth. The purpose of the set is to make a saw kerf in the wood which will be wider than the thickness of the blade of the saw, so that the blade will not bind in the wood. Wet and green wood require more set than hard or dry wood. Not more than % in. of the point of each tooth is set. Some practical saw filers set less than 3/16 in. of the points, maintaining that the saw draws easier and cuts better after the keen points have been slightly worn off.

Success in setting timber saws depends largely on the kind of tools one has for the work. Best results are obtained with a hammer and a setting block, as shown in Figure 75. The saw is placed on the setting block so that the point of the tooth projects over the beveled surface as far as desired, and fig. 75. a setting block in position the point of the tooth is then struck firmly with a light hammer. A set gauge in place on the saw is shown in Figure 76. By its use, it is easy to see the amount of set given to a tooth, and all teeth may be set alike.

The spring set shown in Figure 77 has two places where it may be changed to modify the set. The set-screw at the end of the tool may be loosened, and the anvil moved up or down, thus regulating the length of the point that is set. The abruptness or the angle at which the point of the tooth fig. 7g. a set gauge in use is set or bent over is regu-

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lated by the setscrew at the bottom of the tool. Turning the screw in, increases the set. When using the spring set, the tooth should not be bent over as with a wrench. Pressing the handles together presses the plunger against the point of the tooth and forces it against the anvil, giving it the required set.

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