Chisel

“ A chisel (fig. 29.) is first employed, and connected to this handle by its screw at top. If the ground is tolerably soft, the weight of the two workmen bearing upon the cross bar, and occasionally forcing it round, will soon cause the chisel to penetrate; but if the ground is hard or strong, the workmen strike the chisel down with repeated blows, so as to peck their way, often changing their situation by walking round, which breaks the stones, or other hard substances, that may happen to obstruct its progress. ”

“ The best chisels are those that are file proof. If, after hardening and tempering a chisel, it cannot be cut with a file, it is too hard and the temper must be run out more. If the grain of steel is very fine when broken the chisel had the proper heat when quenched, but if it looks coarse the tool was too hot when cooled and must be annealed, rehardened and tempered. A little judgment will enable one to determine the proper hardness for all tools of this character by noting these temper colors. The above explanation in a general way applies to the working of all carbon steel tools. ”

“ The Cyprian limestone is too soft to furnish the effects and the contrasts which marble offers, so to speak, spontaneously; it is incapable of receiving the charming polish which makes so strong an opposition to the dark shadows of the parts where the chisel has scooped deep. The chisel, whatever efforts it may make and however laboriously it may be applied, cannot impress on such material the strong and bold touches which indicate the osseous structure, and make the muscles and the veins show themselves under the epidermis in Greek statuary. ”

“ Weimmick as we went along, to see what he was like in the light of day, I found him to be a dry man, rather short in stature, with a square wooden face, whose expression seemed to have been imperfectly chipped out with a dull-edged chisel. There were some marks in it that might have been dimples, if the material had been softer and the instrument finer, but which, as it was, were only dints. The chisel had made three or four of these attempts at embellishment over his nose, but had given them up without an effort to smooth them off. ”

“ The narrow end is ground to a chisel edge, which is at right angles to that of the broad end. In form and character this chisel end is exactly like that of a narrow "cold chisel" of steel, in use by engineers. Whether it was used as a narrow adze or axe, or after the manner of a chisel, it is difficult to say.
Fig. 110 is still more chisel-like in character. It is of flint weathered white, but stained in places by iron-mould, from having been brought in contact with modern agricultural implements, while lying on the surface of the ground. ”

“ Being placed in a support or rack against the wall, and quite upright, a chisel—or rather, a series of chisels—are drawn across the surface in straight lines, and perpendicular, by the use of a large T-square. Every time the chisel is drawn with pressure across the varnished back of the glass a portion of the silver is removed, leaving a straight line quite clear or transparent, and, in fact, laying bare the surface of the plate glass. ”

“ The blacksmith’s set of chisels consists of a hot chisel for cutting off hot iron, a cold chisel for cutting cold metal, a hardy, which sets in the square hole in the anvil, C-chisels, which are curved somewhat like the carpenter’s gouge, and a cornering or V-chisel, in which the cutting edges are at a right angle one to the other.
The hot chisel has its edge well curved in its length, and is kept cool by lifting it from the work after each hammer blow, and by occasionally dipping it in water. Lifting it also prevents it from wedging in the work. ”

“ A paring chisel may be ground as thin as 20°, as it does not have to stand heavy blows, and a better edge for the purpose may thus be obtained. In whetting a chisel, the bevel must be carefully maintained, and the back kept perfectly straight, like the face of a plane iron, or it will be impossible to work to a line. ”

“ The single instrument which sufficed to build canoes and houses was the chisel; generally being a piece of old iron obtained from some vessel and fixed in a wooden handle. A stone mallet aided them in using the chisel; and with this simple "kit" of tools they contrived to manufacture plates, bowls, carved oars, and many ornamental things.
Like the men of all savage nations, they made slaves of their captives, and their women. The dress of the latter consisted merely of a short petticoat, manufactured from the fibre of the cedar bark, previously soaked and prepared. ”

“ On the right hand of the illustrations we see three cutting tools made by human hands—i.e. the Chisel, the Stone Adze of{233} Polynesia, and the Steel Adze of this country. We begin with the Chisel.
All those who have even a slight knowledge of anatomy know how curiously exact is the resemblance of the Chisel of civilised life to the front tooth of any Rodent animal. The head of the Beaver is here given as an example, but the tooth of a mouse, rat, or rabbit, which can easily be obtained, is quite as good an example. These teeth are made after a very beautiful fashion. ”

“ A few blocks of stone, sometimes even a single chip of marble, is enough to enable us to tell the history of a building which has been long destroyed. Such a chip may be the only surviving fragment of the edifice to which it belonged, but it preserves the impression of the chisel which fashioned it, that is of the taste and individuality of the artist who held the chisel. We have nothing of the kind in the case of a brick. Bricks were almost always covered with a coat of stucco, so that nothing was required of them beyond that they should be of the right size and of a certain hardness. ”

“ By using a chisel in this way, we reverse the positions of the weight and fulcrum and turn it into a lever of the second order. Suppose we push the side of the chisel—which is 10 inches long—under the lid to the extent of 1 inch, then the advantage we gain in power is as 1 to 10; we thereby increase our strength tenfold. If we push the chisel under the lid for half its length, then our advantage stands as 10 to 5; our strength is only doubled. If we push it still further for two-thirds of its length, then our gain in strength is only as 10 to 6.6; our power is increased by only one-third. ”

“ Every time a fresh chisel is lowered to the bottom it should be worked round in the hole, to test whether it is its proper size and shape; if this is not the case the chisel must be raised at once and worked gradually and carefully until the hole is as it should be. The description of strata being cut by the chisel can be ascertained with considerable accuracy by a skilful workman from the character of the shock transmitted to the rods. ”

“ This method has been generally disused, iron or wood rods substituted in the place of the rope, and a variety of augers and chisels instead of the simple chisel, with appliances for clearing [62] the bore-hole of débris. Figs. 50 to 56 show examples of an ordinary set of well boring tools. Fig. 52 is a flat chisel; Fig. 53 a V-chisel; and Fig. 54 a T-chisel. These chisels are made from wrought-iron, and when small are usually 18 inches long, 21⁄2 inches extreme breadth, and weigh some 41⁄2 lb.; the cutting edge being faced with the best steel. ”

“ In the modern chisel, all the grinding is done on one side. This constitutes the essential feature of the chisel, namely, that the back of the blade is kept perfectly flat and the face is ground to a bevel. Blades vary in width from 1⁄16 inch to 2 inches. Next to the blade on the end of which is the cutting edge, is the shank, Fig. 65. Next, as in socketed chisels, there is the socket to receive the handle, or, in tanged chisels, a shoulder and four-sided tang which is driven into the handle, which is bound at its lower end by a ferrule. ”

“ The tools used in this operation are very simple. The chisel, or jumper, as it is called, varies in size according to the work to be performed, and its edge is more or less pointed to suit the hardness of the rock to be bored. If the hole is to be small and not deep, it may be bored by a single person; with one hand he manages the chisel, which he turns at every blow so as to cross the previous cut, and with the other hand he strikes it with a hammer of six or eight pounds’ weight, occasionally clearing out the hole by means of a scraper. ”

“ The rule holds good in this respect as with every other tool in the kit. Use a tool for the purpose it was made for, and for no other. Acquire that habit.
Cold Chisels.—A cold chisel should never be ground to a long, tapering point, like a wood chisel. The proper taper for a wood chisel is 15 degrees, whereas a cold chisel should be 45 degrees. A drifting chisel may have a longer taper than one used for chipping.
It is a good habit, particularly as there are so few tools which require grinding, to commence the day's work by grinding the chisels, and arranging them for business. ”

“ The hammer and chisel with which this delicate operation was performed are kept in the Jewel House, and are most unlikely-looking instruments. The chisel is in the shape of a deep man’s comb without a handle, and is more like a wedge than a chisel, as generally understood. It is of hardened steel, yet not so hard but that it shows the marks where it struck the diamond. The hammer is equally unconventional, being a solid steel cylinder, like a short rod or truncheon. ”

“ The frieze of that temple of Pallas, which is, perhaps, the most carefully wrought creation of human hands, is not all equally fine in execution. Some parts show the work merely of a skilful carver, while before others we feel that here has been the hand of the great master himself, that the play of the chisel has been governed by the brain that traced the original sketch and thought out the whole marvellous conception. ”

“ A good cold chisel is an indispensable tool in a shop, and one that is very much abused. Therefore, it should be made with the greatest care. In the forging of a good chisel a piece of 5⁄8-in. octagonal tool steel, from 75 to 95 point carbon, is used. The piece is cut six inches long. In doing this the bar may be nicked with a chisel. The nicked part is then set over the outer edge of the anvil. A chisel with a handle is set on the nicks and given a good blow with a sledge hammer, shearing the piece from the bar. ”

“ Implements, which can without hesitation be classed as chisels, are rare in Ireland, though long narrow celts approximating to the chisel form are not uncommon. These are usually of clay-slate, or of some metamorphic rock. I have, however, specimens of oval section not more than an inch wide, and as much as 5 inches long, with narrow straight edges, which seem to be undoubtedly chisels. I do not remember to have seen a specimen in flint, those described by Sir W. Wilde [10] being more celt-like in character. ”

“ If you wish them to live and increase, you must chip off a bit of the rock on which they are growing. With a chisel, or even a knife, you can do it without difficulty, for the soft slate scales and crumbles under a slight blow. ”

“ This form affords a firm grip to the hand, the end e being applied to the operator’s shoulder. The shape of handle for a firmer chisel is shown in Fig. 2746.
Chisels require great care both in grinding and oilstoning them, being held very lightly upon the grindstone when finishing the grinding so as to avoid as far as possible the formation of a long [II-272] feather edge. The flat face of the chisel should never be ground, as that would make it rounding in its length, hence there would be nothing to guide it in cutting straight and the value of the tool would be almost destroyed. ”

“ The Chisel.—This tool has a bevelled edge and is used for paring off the wood.
Unless you are quite careful there is danger of cutting your left hand in using the chisel, and it is best not to try to hold the work, but to fasten it in the vice; your left hand placed on the tool will steady and control it.
Fig. 4 Fig. 5.
Auger-bit and Brace.—For drilling large holes the auger-bit and brace are necessary. The bit resembles a gimlet in its spiral edge, but is not wedge-shaped, and the hole it makes is of unvarying size. You may have several bits for large or smaller holes. ”

“ When the teeth are large, as in the Beaver, and the jaws powerful, their force is something wonderful, tree-trunks of considerable size being cut down quite easily.
Perhaps some of my readers may not be aware that the Chisel is constructed on exactly the same principle as the tooth of the Rodent animal. It is not entirely made of steel, as is generally thought. In the first place, a valuable material would be needlessly wasted, and, in the next place, the tool would not keep its edge except with infinite labour in grinding. ”

“ A typical form of sidewise chiseling is the cutting out of a dado, Fig. 70. The work may be placed on the bench-hook or held in the vise with the side up from which the groove is to be cut. The chisel is pushed directly across the grain, the blade being somewhat inclined to the upper surface so as to cut off a corner next the saw kerf. After a few cuts thus made with the chisel inclined alternately both ways, the ridge thus formed is taken off, Fig. 71. In this way the surface is lowered to the required depth. If more force be required, the palm of the hand may be used as a mallet. ”

“ Chisels are either for paring the wood, and are used with the hand; or are intended to cut into the thickness of the wood, and are then struck with a large wooden hammer, called the mallet. The gouge is a curved chisel, used for cutting mouldings or making round edges. ”

“ The best chisels for doing this are those that have got, I might say, very fine points, but the handles of which are at least as small as the little finger. With this chisel, subbia, you approach to within at least half a finger of what is called the penultima pelle, the last skin but one; then you take a chisel, scarpello, with a notch in the middle of it, [277] and carry on the work further till it be ready for the file, lima, & this file again is called the lima raspa, or roughing file, or occasionally scuffina. There are ever so many sorts of this tool ”