TOOLS USED IN STONE CUTTING.
The Hammer is a heavy tool, weighing from 20 to 30 pounds, used for roughly shaping stones as they come from the quarry and for knocking off projections. This is used for only the roughest work.
The Face Hammer has one blunt and one cutting end, and is used for the same purpose as the double-face hammer where less weight is required. The cutting end is used for roughly squaring stones preparatory to the use of the finer tools.
The Cavil has one blunt and one pyramidal or pointed end, and weighs from 15 to 20 pounds. It is used in quarries for roughly shaping stone for transportation.
The Pick somewhat resembles the pick used in digging, and is used for rough dressing, mostly on limestone and sandstone. Its length varies from 15 to 24 inches, the thickness at the eye being about 2 inches.
The Axe or Pean Hammer has two opposite cutting edges. It is used for making drafts around the arris or edge of stones, and in reducing faces, and sometimes joints, to a level. Its length is about 10 inches and the cutting edge about 4 inches. It is used after the point and before the patent hammer.
The Tooth Axe is like the axe, except that its cutting edges are divided into teeth, the number of which varies with the kind of work required. This tool is not used in cutting granite or gneiss. The Bush Hammer is a square prism of steel, whose ends are cut into a number of pyramidal points. The length of the hammer is from 4 to 8 inches and the cutting face from 2 to 4 inches square. The points vary in number and in size with the work to be done. One end is sometimes made with a cutting edge like that of the axe. The Crandall is a malleable-iron bar about 2 feet long slightly flattened at one end. In this end is a slot 3 inches long and i-inch wide. Through this slot are passed ten double-headed points of Finch square steel 9 inches long, which are held in place by a key.
The Patent Hammer is a double-headed tool so formed as to hold at each end a set of wide thin chisels. The tool is in two parts, which are held together by the bolts which hold the chisels. Lateral motion is prevented by four guards on one of the pieces. The tool without the teeth is 51 X 21 X.11 inches. The teeth are 21 inches wide; their thickness varies from to t of an inch. This tool is used for giving a finish to the surface of stones.
The Hand Hammer, weighing from 2 to 5 pounds, is used in drilling holes and in pointing and chiselling the harder rocks.
The Mallet is used where the softer limestones and sandstones are cut.
The Pitching Chisel is usually of 11-inch octagonal steel, spread on the cutting edge to a rectangle of X 21 inches. It is used to make a well-defined edge to the face of a stone, a line being marked on the joint surface, to which the chisel is applied and the portion of the stone outside of the line broken off by a blow with the hand ham mer on the head of the chisel.
The Point is made of round or octagonal steel from I to 1 inch in diameter. It is made about 12 inches long, with one end brought to a point. It is used until its length is reduced to about 5 inches. It is employed for dressing off the irregular surface of stones, either for a permanent finish or preparatory to the use of the axe. According to the hardness of the stone, either the hand hammer or the mallet is used with it.
The Chisel is of round steel of 1 to 1-inch diameter and about 10 inches long, with one end brought to a cutting edge from 1 inch to 2 inches wide; is used for cutting drafts or margins on the face of stones.
The Tooth Chisel is the same as the chisel, except that the cutting edge is divided into teeth. It is used only on marbles and sandstones.
The Splitting Chisel is used chiefly on the softer stratified stones, and sometimes on fine architectural carvings in granite.
The Plug, a truncated wedge of steel, and the feathers of half round malleable iron, are used for splitting unstratified stone. A row of holes is made with the drill on the line on which the fracture is to be made; in each of these two feathers are inserted, and the plugs lightly driven in between them. The plugs are then gradually driven home by light blows of the hand hammer on each in succession until the stone splits.
Machine Tools. In all large stone yards machines are used to prepare the stone. There is a great variety in their form, but since the kind of dressing never takes its name from the machine which forms it, it will be neither necessary nor profitable to attempt a description of individual machines. They include stone saws, stone cutters, stone grinders, stone polishers, etc.