THE SCREW-DRIVER
The need of a screw-driver is too obvious to require special mention. They are made with blades from two inches up to thirty inches long, and have round, flat, or corrugated handles. The best grip is obtained on either a flat or corrugated one, and two sizes are desirable, a small one with about a three-inch blade, the other with an eight or ten. ([Fig. 126].)
Some of the magazine brad awls containing a dozen awls and screw-driver are very convenient, but the combinations supposed to contain a whole tool outfit, including saws, are poor investments.
Ratchet screw-drivers, from which the hand is not removed during the operation of driving or withdrawing a screw, are on the market, but they are luxuries rather than necessities.
Pliers with wire-cutting attachments are convenient, and should be added to the kit when possible; some of them are powerful enough to cut a heavy wire nail. ([Fig. 127].)
Fig. 126. Screw-drivers
The Mallet. This simple tool is made in a dozen different forms for various trades. The round-headed kind is perhaps the cheapest. It is made of hickory or lignum vitæ. ([Fig. 128].)
The best form for woodwork has an oblong or square head of lignum vitæ. The handle should pass clear through the head and be fastened with a wedge.
Fig. 127. Pliers
A blow from this tool does not shatter the tool handle as would a blow from a hammer. A comparison of the two blows might be likened to the action of gun powder and dynamite. The slow burning powder represents the action of the mallet. The hammer should never be used on a chisel or gouge.
Hand screws for holding glued-up work together, sometimes for holding special work on the bench top, are made of wood, with either wood or metal spindles. For ordinary work, the jaws should be parallel, but special forms are on the market which will hold irregular forms, as shown in [Fig. 129].
Fig. 128. The mallet
They are made in several sizes, from little ones with 4-inch jaws up to 22-inch jaws. For large and heavy work, clamps of wood or metal may be had as large as eight feet in length. They are useful in the making of drawing boards, doors, etc., but are not a real necessity for boys' ordinary woodwork. Clamps in the form of trestles for specially important large work are made as large as twelve feet in length.
For ordinary purposes, a pair of 6-inch and a pair of 12 or 14 inch wood hand screws will answer. The ingenuity of the young woodworker will suggest other ways of holding glued-up work in the absence of hand screws, such as winding with heavy twine or rope, and twisting a stick through the strands, after the old method of tightening a buck saw or turning saw. In building up a drawing board and gluing the strips together, the requisite pressure may be obtained by laying it on the floor between blocks temporarily nailed there, and wedges driven in, after the method described for picture frames.
Fig. 129. Clamp and hand screws
A large part of the value derived from woodwork is in the exercise of ingenuity required to meet unexpected contingencies. Just so the owner of an automobile learns more about mechanics and the construction of his machine by being obliged to make repairs on the road, miles from any repair shop, and with a limited number of tools and appliances.