Читать книгу The Handyman's Book of Tools, Materials, and Processes Employed in Woodworking - Paul N. Hasluck - Страница 101

Two kinds of setting are used for hand saws—namely, spring-setting and hammer-setting. In the former the teeth are bent from the line by a saw-set; in the latter they are set over by a blow from a hammer. First, spring-setting will be described. For this purpose is used a saw-set (Fig. 295), which is made of steel, and has a series of graduated notches cut into each edge. Figs. 295 and 296 show the ordinary kind of saw-set, whilst the one illustrated by Fig. 297 has a gauge attached to it. To use a saw-set, the back of saw is held in the left hand (as A, Fig. 298), or it is gripped in a vice (see Fig. 299), and the handle of the saw-set is taken in the right hand. Then select a notch that easily fits over the tooth, and proceed very carefully to bend alternate teeth towards the body by pressing the handle downwards. Care must be taken to make the pressure equal upon each tooth, or they will be set out of line. The top of the tooth only must be bent, as a (Fig. 300). Should the whole of the tooth be bent, b, it is very likely to break out. Having set the teeth upon each side, glance down the edge to see if the set is true and regular. The forefinger may be run down the blade at the same time to mark any irregularity, which may be at once corrected by bending the faulty tooth in the desired direction. Figs. 301 and 302 fully illustrate this, Fig. 301 being an end view. Care should be taken to pull the tooth over only a very little; it is far easier to give it a little more than to take some off, and with the slighter amount of bending there is less likelihood of breaking off the teeth. A rip saw requires but very little set; a hand saw about a fourth of its own thickness on each side. After setting a saw, lay it flat on a board, then take a file without its handle and slide it down the sides of the teeth, taking care that it leans towards the back of the saw. This will regulate the set, and if a tooth or two is bent over a little too much, it will file off the excess. After this, pass the oilstone down the same way as the file.

Fig. 298.—Setting Saw held in Hand.

Fig. 299.—Setting Saw held in Vice.

Fig. 300.—Set of Saw Teeth.