Fig. 518.
To find the centres for boring, so that the holes bored in the two pieces shall be in line, you can cut off the heads of some small wire brads so that they will be pointed at both ends. Stick the brads into one piece where the centres of the holes should be. Then press this piece against the other in the position it is to take when the work is done and the brads will of course prick holes in the second piece exactly corresponding to those in the first piece (Fig. 517). Instead of brads, small shot can be used in a similar manner. It is well to take a round-pointed awl, or some such tool, and carefully prick a small hole with it at each of the points marked. This is to start the spur of the bit exactly at the point, as the spur sometimes has a way of working off to one side, so that the hole may not be in exactly the right place. The hardest part, however, is to bore the holes exactly at right angles to the surface, as a slight deviation in either or both may make a bad angle where the two holes meet. You can sometimes lay the pieces flat on the bench and arrange boards or blocks so as to guide the bit straight. The dowels must be thoroughly dry. It is better to have them a trifle too large, rather than too small, for you can easily trim them down to a snug fit. Scratch them lengthways with the toothed-plane, or with the edge of a file. Countersink a little hollow around the opening of each hole (see Countersink), to catch the surplus glue which would otherwise form a rim around the dowel (Fig. 517). Before gluing you should fit the work together once, as it is very awkward to make changes after the gluing is begun. When the parts fit accurately, take the joint apart for gluing. Brush a little glue around the inside of one of the holes, dip one end of a dowel in the glue and drive into place. Wipe off the superfluous glue and repeat the process with each of the dowels in that half of the joint. Leave this to dry a day, or more if you can. Then clean any hardened glue from the dowels and glue them, as before, into the other piece, this time putting glue on the flat surfaces which are to come together. The whole should be firmly clamped and left to dry (see Gluing and Clamps). Dowels are sometimes used in joining the edges of pieces, as in Fig. 518, and in many other joints too numerous to be specified (see Joints and Jointing).
Dowelling looks very easy, but it is usually hard for the beginner to bore the holes straight and to make the pieces fit accurately.
Dowel-Plate.—A steel plate with various holes of such sizes that pins made by driving blocks of wood through them will drive snugly into the holes made by the corresponding bits. This is useful in fitting dowels.
Drawers.—The making of well-fitting and smoothly running drawers is an operation requiring much skill—more skill than can be expected of the beginner, or, in fact, than is attained by the average workman. The beginner should, however, have some understanding of the work, even if he does not attain a high degree of skill in its execution.
Bear in mind that it is much easier to make a drawer which is narrow and long (from front to back) run smoothly than one which is wide across the front, but shallow from front to back.
The more accurately the case which holds the drawers is made, the easier it is to make smoothly running drawers. In good work having more than one drawer, a horizontal frame is fitted beneath each drawer for it to run on. These frames, as well as the whole case, should be free from winding, and it is also important that the stock for the drawers should be true. The front and sides of a drawer should be got out to fit very snugly in their places. The piece for the back is narrower than the front piece, to allow for the bottom (Fig. 521), and is often cut off at the top also. The front, sides, and back can be put together with any suitable form of joint. Dovetailing is by far the best way, but it is difficult for the beginner (see Dovetailing). The joints shown in Fig. 519 can very well be used for ordinary work. These can be quickly made by machinery (see Joints). See also Gluing and Clamps.
Fig. 519.