Handwork in Wood Part 10
_Foerstner bits_, Fig. 133, are peculiar in having no spur, but are centered by a sharp edge around the circ.u.mference. The size is indicated on the tang, in 16ths of an inch. They are useful in boring into end grain, and in boring part way into wood so thin that a spur would pierce thru. They can be sharpened only with special appliances.
_Expansive-bits_, Fig. 134, are so made as to bore holes of different sizes by adjusting the movable nib and cutter. There are two sizes, the small one with two cutters, boring from 1/2" to 1-1/2" and the large one with three cutters boring from 7/8" to 4". They are very useful on particular occasions, but have to be used with care.
_Reamers_, Fig. 135, are used for enlarging holes already made. They are made square, half-round and six cornered in shape.
_Countersinks_, Fig. 136, are reamers in the shape of a flat cone, and are used to make holes for the heads of screws. The rose countersink is the most satisfactory form.
[Ill.u.s.tration: Fig. 138. Washer-Cutter.]
The _washer-cutter_, Fig. 138, is useful not only for cutting out washers but also for cutting holes in thin wood. The size is adjustable.
3. CHOPPING TOOLS.
The primitive celt, which was hardly more than a wedge, has been differentiated into three modern hand tools, the _chisel_, see above, p. 53, the _ax_, Fig. 139, and the _adze_, Fig. 141.
The _ax_ has also been differentiated into the _hatchet_, with a short handle, for use with one hand, while the ax-handle is long, for use with two hands. Its shape is an adaption to its manner of use. It is oval in order to be strongest in the direction of the blow and also in order that the axman may feel and guide the direction of the blade.
The curve at the end is to avoid the awkward raising of the left hand at the moment of striking the blow, and the k.n.o.b keeps it from slipping thru the hand. In both ax and hatchet there is a two-beveled edge. This is for the sake of facility in cutting into the wood at any angle.
There are two princ.i.p.al forms, the common ax and the two bitted ax, the latter used chiefly in lumbering. There is also a wedge-shaped ax for splitting wood. As among all tools, there is among axes a great variety for special uses.
[Ill.u.s.tration: Fig. 139. Ax.]
[Ill.u.s.tration: Fig. 140. Shingling Hatchet.]
[Ill.u.s.tration: Fig. 141. Carpenter's Adze.]
The _hatchet_ has, beside the cutting edge, a head for driving nails, and a notch for drawing them, thus combining three tools in one. The shingling hatchet, Fig. 140, is a type of this.
The _adze_, the carpenter's house adze, Fig. 141, is flat on the lower side, since its use is for straightening surfaces.
WOOD HAND TOOLS.
REFERENCES:[*]
(1) Cutting.
Goss, p. 22.
Smith, R. H., pp. 1-8.
Chisel.
Barnard, pp. 59-73.
Selden, pp. 44-50, 145-147.
Barter, pp. 93-96.
Griffith, pp. 53-64.
Goss, pp. 20-26.
Sickels, pp. 64-67.
Wheeler, 357, 421, 442.
Knife.
Barnard, pp. 48-58.
Selden, pp. 26-28, 158.
Saw.
Griffith, pp. 20-27.
Barnard, pp. 114-124.
Selden, pp. 41-43, 179-182.
Wheeler, pp. 466-473.
Hammacher, pp. 309-366.
Goss, pp. 26-41.
Sickels, pp. 76-79, 84.
Smith, R. H., 43-55.
Diston, pp. 129-138.
Plane.
Barnard, pp. 74-80.
Selden, pp. 11-26, 165-175.
Sickels pp. 72-75, 116.
Wheeler, pp. 445-458.
Hammacher, pp. 377-400.
Smith, R. H., 16-31.
Larsson, p. 19.
Goss, pp. 41-52.
Barter, pp. 96-109.
Griffith, pp. 28-45.
(2) Boring Tools.
Barnard, pp. 125-135.
Goss, pp. 53-59.
Griffith, pp. 47-52.
Seldon, pp. 38-40, 141-144.
Wheeler, pp. 353-356.
(3) Chopping Tools.
Barnard, pp. 80-88.
[Footnote *: For general bibliography see p. 4.]
CHAPTER IV, CONTINUED.
WOOD HAND TOOLS.
4. Sc.r.a.pING TOOLS.