Figure 13.
The Bit Stock.—Even if the gunsmith have a lathe there is much work that can be done to advantage with a common bit-stock. But as the drills and tools used in the lathe generally have round shanks by which to hold them in the chuck, the square hole where bits and tools are held in the bit stock must be filled by brazing or soldering a piece of iron into it and boring a hole to fit the shank of the lathe tools. It is advisable to have these shanks about seven-sixteenths diameter, as explained under the heading “Shanks of Tools.”
In holding small drills made of steel wire or twist drills a small drill chuck must be fitted to the bit stock.
A small solid chuck with a quarter inch hole may be made with a shank to fit the seven-sixteenth hole. A set screw must be fitted to hold the shanks of the two sizes mentioned.
Figure 14.
Bottoming Tools.—Bottoming tools are used for letting in locks, cutting out for escutcheons, and are useful in other places where a chisel cannot be made to operate. The form of this tool is shown in [Fig. 14]. It consists of a square or round shank about three-sixteenths or a quarter-inch in diameter and about six inches long. At one end a wooden handle is attached, and the other end is bent at an angle which is about half an inch or perhaps a little more, and on this angle is another one turned parallel with the shank and which is about three-eighths of an inch long. This is the cutting end and is fashioned like the cutting edge of a chisel, and is about a quarter of an inch wide. The bottom side, as it would be held for use, is ground flat and the upper side bevelled like a chisel. The cutting edge may be square or rounded to suit round places as letting in the bridle of a lock. The size given is that generally used, but if it be made about twice this size it will be found very useful in letting in octagon rifle barrels; if the tool be made larger and hollow like a gouge it is very useful in letting in round gun barrels. In letting in break off straps it will be found to take the place of a chisel to some advantage.
Chequering Tools.—The tools used for chequering are very simple. Imagine a small saw, or rather two small saws about one inch or more long, made at the end of a straight steel shank. The form is given in [Fig. 15]. The double saw can be made by filing it as one thick saw and then cutting a groove lengthwise with it. In using, one blade first forms a groove and the other blade works the next cut; as the first cut is finished, another mark is being made while so doing. This insures equal width of the cuts. Care must be exercised in using them so as not to tear the wood. A fine cut, sharp edged, three square or a small half round file may be used to finish the work if desired.
Figure 15.