Extracts From " HANDBOOK FOB LUMBERMEN," Henry Disston & Sons.

The teeth of a hand-saw should be filed so true that, on holding it up to the eye and looking along its edge, it will show a central groove down which a fine needle will slide freely the entire length; this groove must be angular in shape and equal on each side, or the saw is not filed properly and will not run true.

Fig. 4 shows how the groove should appear on looking down the edge of the saw; the action should be such that the bottom of kerf will present the appearance as shown in Fig. 5, and not like Fig .6; the cutting action is as shown in Fig. 7; the cutting being done with the outside of tooth, the fibre of the wood is severed in the two places and the wood is crumbled out from point to point by the thrust of saw.

The proper amount of bevel to give the teeth is very important, as is demonstrated by the above figures, for if too much bevel is given, the points will score so deeply that the fibres severed from the main body willnot crumble out as severed, but be removed by continued rasping, particularly in hard woods, as they require less bevel, as well as pitch, than soft wood.

Fig. 8.

Fig. 8 shows a six-point cross-cut saw filed with a medium amount of bevel on front or face of tooth, and none on the back. This tooth is used in buck-saws, on hard wood, and for general sawing of woods of varying degrees of tenacity. This style of dressing is the best, but a number of saws each having teeth suited to its particular work, will be found more advantageous than trying to make one saw serve for all kinds of handsaw work.

We will now consider the cross-cut saw tooth, in re" gard to rake or pitch; this being one of the most important features, too much care cannot be taken to have the correct amount of pitch for the duty required. To illustrate this, Fig. 9 represents a board, across which we wish to make a deep mark or score with the point of a knife; suppose we hold the knife nearly per-pendicular as at B, it is evident it will push harder and will not cut as smoothly as if it was inclined forward

Fig. 9.

as at i; it follows then that the cutting edge of a cross-cut saw should incline forward as at C, rather than stand perpendicular as at D.

Too much hook or pitch, and too heavy a set are very common faults, not only detrimental to good work but ruinous to tha saw; the first by having a large amount of pitch, the saw takes hold so keenly that frequently it "hangs up " suddenly in the thrust - the result, a kinked or broken blade; the second, by having too much set, the strain caused by the additional and unnecessary amount of set is out of proportion to the strength of the blade, and is broken in the same manner. The most general amount of pitch used is 60°, though this may be varied a little more or less to advantage, as occasion may demand.

The next point to be considered is the bevel, or fleam, of the point. In Figs. 10, 11 and 12, the filer, as

Fig. 10.

in all cases, files from the heel to the point, which is the only correct way. The file is supposed to he horizontal to the perpendicular of the side of saw, and on an angle of about 45° longitudinally with the length, measuring from file line toward heel.

Fig. 10 is a five and a half cross -cut saw showing the same amount of fleam front and back ; this saw is best suited for workin soft wood, and where rapid, rather than fine work is required. A shows the position of the file, B an exaggerated view of shape of point, and C the shape of point.

Fig. 12.

Fig. 11 is a seven point saw for] medium hard woods, illustrated in same manner as Fig. 10. This tooth has less fleam on the back, which gives a shorter bevel to point, as at C. Fig. 12 is a still finer saw, having ten points to theinch. This saw has no fleam on back, the result being very noticable at C and B. Thisstyle of point is for hard wood.

It will be seen that the bevel on the front of teeth in Figs. 10, 11 and 12 is the same, but the bevel of the point looking the length of saw is quite different, consequent upon the difference in the angles of the backs. Concluded in January number.

Fig. 11.

The wood used in lead-pencil making must be close and straight-grained, soft so that it can readily be whittled, and capable of taking a good polish. No better wood has been found than the red cedar, a native of the United States, a durable compact, and fragrant wood, which today is used almost exclusively by pencil makers the world oAer. The best quality is obtained from the southern states, Florida and Alabama in particular.