Handwork in Wood Part 24

The mitered ledge, Fig. 268, No. 58, makes a very neat, strong joint which can be nailed or glued, but is more difficult to fit than a simpler joint.

The dovetail joint, Fig. 267, No. 48, is very strong and honest, but the joint is prominent from the outside and it takes much time and labor to make. It is glued.

The blind dovetail, Fig. 267, No. 51, is very neat and strong, and the joint is entirely concealed when done, but is very difficult to make.

_The Bottoms of Boxes._ The plain or full bottom, Fig. 284, A, is likely to shrink (see dotted line), and it is held in place only by the friction of the nails. The extended bottom, Fig. 284, B, overcomes the objection to shrinkage and adds a decorative feature. The bottom may be set in, Fig. 284, C. This is stronger than the plain bottom, but the nail holes show. The bottom may be rabbeted in, Fig. 284, D.

This is better than the set-in bottom so far as the showing of the nail holes goes, for the nails may be driven in from below, and a little shrinkage is not conspicuous. It is practicable, if a rabbet or mitered joint is used in the sides, but if the side pieces are b.u.t.ted or dadoed, the rabbet for the bottom shows. This may be cleverly concealed by an insert, but that is patchwork, and not first-rate construction.

Reinforced bottom, Fig. 284, E. A plain or full bottom is sometimes covered by a base or cover strip to hide the joint and secure the bottom, as in tool chests. This strip may be mitered at the corners.

[Ill.u.s.tration: Fig. 284. Methods of Attaching Box Bottoms.]

_The Lids of Boxes._ The simplest form is a full flat cover, Fig. 285, A, which may be nailed or screwed to the box, as in packing cases. The cover may slide into a groove, Fig. 285, B, along the sides and into one end, the other end being lowered to admit it. The cover may have cleats on its underside, Fig. 285, C, which fit just inside the box and keep the top in place. The cleats also prevent the top from warping. This is a common j.a.panese construction, even in fine boxes.

The j.a.panese tie the top on with a tape or ribbon.

The lid may be boxed, Fig. 285, D, that is, portions of the sides may be affixed to the top. These extra pieces are a help to stiffen the top and to keep it from warping. A boxed top may have the top board flush with the sides, Fig. 285, E. The disadvantage of this is that the top may shrink and part from the sides and give a bad appearance.

The overlapping top, Fig. 285, F, obviates this trouble of shrinkage and adds a decorative element. In this case the top may be glued on or screwed from below thru the side strips.

The top may be mitered into the sides, Fig. 285, G. The shrinkage trouble still obtains here. Otherwise the appearance is excellent.

The top may be paneled into the sides, Fig. 285, H. This has a good appearance if the sides are mitered and ledged but not if the sides are b.u.t.ted or dadoed, because then the groove for the top shows.

[Ill.u.s.tration: Fig. 285. Forms of Box Construction.]

Any of these lids may be made removable or hinged, except the sliding top. For methods of hinging see p. 132.

In gluing boxes together, it is a good plan to glue the ends and sides together first and to let these joints dry before gluing on the bottom and, in the case of a boxed top, Fig. 285, D, the top. Care must be taken to see that the sides do not bow under the pressure. To prevent this, one or more false, temporary part.i.tions as A, B, in Fig. 286, of exactly the length to keep the sides straight, may be inserted.

In gluing together boxes with rabbeted joints, Fig. 285, H, pressure should be applied in both directions. In gluing on the bottom of a box that is also to be nailed, the nails should be driven into the bottom first, so that the points just come thru. These points sticking into the sides will prevent the bottom from slipping when pressure is applied. It is often undesirable to have nail heads show, as in a top. In such a case, and also to prevent the top from slipping under pressure, a couple of small brads may be driven part way into the upper edges of the sides, the heads bitten off with the nippers, and points filed on the projecting portion.

[Ill.u.s.tration: Fig. 286. Glueing Together a Box.]

_Drawers._ In the best form, the sides are dovetailed to the front for strength, Fig. 287, for whenever the drawer is opened the front tends to pull away from the sides. This dovetail is half blind, so that the joint will not appear when the drawer is shut. In order that the drawer may always run freely and yet the front fit the opening as close as possible, it is common practice to cut a shallow rabbet on the ends of the front, so that the body of the drawer is a little narrower than the front is long, Fig. 287. Or the front may be attached to the sides with a dado tongue and rabbet joint, Fig. 266, No. 27, p. 179.

[Ill.u.s.tration: Fig. 287. Dovetailed Drawer Construction.]

The bottom is grooved into the sides with its grain parallel to the front and fastened only to the front so that it has plenty of play for shrinkage. The back is dadoed into the sides, with either a straight dado, Fig. 266, No. 25, p. 179, or dovetail dado, Fig. 266, No. 28, and rests on the bottom. The extension of the bottom beyond the back allows ample room for shrinkage.

The best machine-made drawers are now made with the bottom paneled or dadoed in all around so that papers cannot slip out. The back, as well as the front, is dovetailed.

_Directions for Making a Table Drawer._ Dress the front and sides to size. Fit the front of the drawer to its place in the table or cabinet, leaving a little play all around it. Plow the groove in the front and sides for the drawer bottom. For ordinary drawers, a groove 1/4" wide is proper. If the ends of the front are to be rabbeted (see above), do this next. The sides are best joined to the front with the half-blind dovetail joint. (For directions see p. 166). After fitting these, lay out and cut the dadoes for the back of the drawer. Prepare the bottom of the drawer thus: the grain should run right and left, never front and back. If the drawer is so long as to require it, glue-joint the bottom, and fit it snugly to place. There need be no play right and left, and the bottom should extend as far back as the sides. If necessary, bevel the under side to fit the grooves. a.s.semble all the parts to see that they fit, take them apart, glue the sides to the front and back, slip the bottom into place, apply the clamps, and see to it that all joints are square, using a diagonal brace if necessary, Fig. 294. Fasten the bottom to the front by means of a thin block glued into the interior angle between the under side of the bottom and the back side of the front. When dry, clean up the drawer and fit it to its place.

(3) PANEL STRUCTURES

These include doors and cabinets of all sorts. The principle of panel or cabinet construction is that there shall be a frame composed of narrow members whose grain follows the princ.i.p.al dimensions. In the best construction this frame is mortised and tenoned together and within this frame there is set a thin board or panel which is free to shrink or swell but is prevented from warping by the stiffer frame.

The object is to cover an extended surface in such a way that the general dimensions and good appearance will not be affected by whatever shrinkage there is. Since the frame itself is made up of narrow pieces, there is but little shrinkage in them. That shrinkage is all that affects the size of the whole structure, because wood does not shrink longitudinally to any appreciable extent. The shrinking or swelling of the panel does not affect the general size. The cross construction of the frame also prevents warping, since, in the best construction every joint is mortised and tenoned. The panel may simply be fastened on the back of the frame, but a better construction is to insert it in a groove made in the inside of the frame in which the panel is to lie and have free play. The panel may be made of one board or of matched boards, may be plain or have raised or carved surfaces, or be of gla.s.s; and the joints between frame and panel may be embellished with moldings mitered in, but the principle is the same in all cases.

The frame of a door, Fig. 288, ill.u.s.trates the panel construction. The upright, outside pieces are called the "stiles," the horizontal pieces the "rails." There are also the "top-rail," the "bottom-rail," the "lock-rail" (where the door-k.n.o.b and lock are inserted), and sometimes the "frieze-rail" between the lock rail and the top rail. The "muntin"

is the upright between the two stiles.

[Ill.u.s.tration: Fig. 288. Door, Ill.u.s.trating Panel Construction: S.

Stile; T. R. Top Rail; L. R. Lock Rail; B. R. Bottom Rail; M. Muntin; P. Panel; A. Double Mortise-and-Tenon; F. Fillet; A. B. C. Forms of Panels.]

The joint commonly used is the haunched or relished mortise-and-tenon, Fig. 267, No. 42, p. 180; (See p. 163 for directions for making). The tenon is sometimes doubled, Fig. 288, and a fillet (f) may be inserted to cover the ends of the tenons, or the joint may be a blind mortise-and-tenon, Fig. 266, No. 32, or in cheap construction, dowels may be used. The best doors are now made with cores of pine covered on the visible sides with heavy veneer. Large surfaces are covered by increasing the number of parts rather than their size, as in wainscoting.

Picture-frames also belong in this cla.s.s of structures, the gla.s.s taking the place of the panel. They are made with mortise-and-tenon joints, Fig. 266, No. 33, slip joints, Fig. 267, No. 46, dowelled b.u.t.t joints, Fig. 264, No. 8, end lap joints, Fig. 265, No. 17, and, far more commonly, mitered joints, Fig. 268, No. 52. Mitered joints are the easiest to make, for the joints can be cut in a miter-box, Fig.

181, p. 104, and glued in a picture-frame-vise, Fig. 172, p. 101. This joint needs reinforcement by nails, Fig. 268, No. 52, by dowels, No.

53, or by splines, No. 55. If the sides are of different widths, the fitting of the joint is more difficult. Mitered joints are the only kind suitable for molded frames. The rabbets are cut out with a rabbeting-plane before mitering and a.s.sembling.

The principle disadvantage of a mitered joint is that, if the wood shrinks at all, it opens at the inside corners, as in Fig. 289, because wood shrinks sidewise but not lengthwise.

[Ill.u.s.tration: Fig. 289. The Way a Mitered Joint Opens on Account of Shrinkage.]

In window sashes, the dovetail joint, Fig. 267, No. 47, is the common one at the upper end of the lower sash and the lower end of the upper sash, and the mortise-and-tenon joint modified is used at the lower end of the lower and upper end of the upper sash. The gla.s.s takes the place of the panel. In blind sashes, the pinned mortise-and-tenon joint, Fig. 267, No. 38, is commonly used.

When panels are joined together to enclose a s.p.a.ce, then we have what is properly called cabinet construction. Ill.u.s.trations are cabinets, bureaus, desks, lockers, chests, etc.

In all these cases, the constructed panels may be treated as separate boards and joined together with dowel pins or splines or dadoed together without any other framework, tho the corners are often reinforced by cleats or blocks glued into them. Sometimes, however, as in chests, Fig. 290, posts are used instead of stiles, and rails are mortised or doweled into them and the panels set into grooves in both posts and rails. In this case the bottom is raised from the floor, and may be dadoed into the bottom rails, or dowelled into them or even supported by strips attached along their lower inside edges. The chest really is a union of both paneled and framed structures.

[Ill.u.s.tration: Fig. 290. Chest Construction.]

(4) FRAMED STRUCTURES

The principle of the framed structure is similar to that of the panel construction in that the object is to allow for shrinkage without harm to construction and also to economize materials. Common examples are tables, chairs, work-benches, and frame houses.

_The Making of a Table._ The standard height of a table is 30". There should be 25" clearance under the rails. This leaves approximately 4" for the width of the rails. a.s.suming that the table is to be of a simple straight line type with one drawer, the following method of procedure is suggested:

Cut the boards for the top to the approximate length and stick, (see p. 47) and clamp them, so as to season them as well as possible before jointing.

Dress to size the legs and rails. Stand the legs in their proper positions relative to each other, and mark them F R (front right), F L (front left), B R (back right), and B L (back left). Plow out the grooves on the inside of the rails for the fastenings of the top, Fig. 297, D, if they are to be used. Lay out and cut the tenons and mortises for the end rails and back rail.

The proper form of the tenon is one with a wide shoulder above it so that the top of the leg above the mortise will not shear out. The rails should be set near the outside of the leg so that the tenon may be as long as possible and the portion of the leg inside it as strong as possible. A haunched mortise-and-tenon joint, Fig. 267, No. 43 is sometimes used, giving additional lateral stiffness to the rail. The proper proportions are shown in Fig. 291. When cut, these parts should be temporarily a.s.sembled to see if they fit.

[Ill.u.s.tration: Fig. 291. A. Cross-Section Thru Back Left Leg and Adjoining Rails of Table. (Plan). B. Elevation, Showing Wide Shoulder on Tenon of Rail.]

Inasmuch as a drawer takes the place of a front rail, the front legs must be tied together in some other way. For this purpose two stringers or drawer rails may be used, their front edges being as far from the face of the legs as are the rails from the side and back. The upper drawer rail may be dovetailed at both ends into the tops of the legs, as shown in Fig. 292. If this takes more room than can well be spared from the depth of the drawer, it may be omitted, but it adds greatly to the stiffness of the table and is an excellent means of fastening on the top by the use of screws pa.s.sing thru it.

[Ill.u.s.tration: Fig. 292. Table Construction: Upper Drawer Rail of Table Dovetailed into Left Front Leg.]

The drawer rail, also called the fore edge, is long enough to partly overlap the side rails, into the lower edges of which it is gained so as to be flush with them, and may be fastened to them with screws, Fig. 293. The construction may be further strengthened by also doweling the end of this stretcher into the legs. If there are two drawers, the part.i.tion between them may be doweled or gained into these upper and lower stretchers.

[Ill.u.s.tration: Fig. 293. The Fixing of a Drawer Rail, Seen From Below.]

If the legs are to be tapered or otherwise shaped, that should be done next. Then glue and a.s.semble the end rails with their proper legs, taking care to see not only that the joints come up square, but that the legs are in the same plane. Finally a.s.semble the whole, inserting, if necessary, a temporary diagonal brace to insure squareness, Fig.

294. When dry, clean up the joints. For the making of a table drawer, see above, p. 191.

[Ill.u.s.tration: Fig. 294. Brace to Insure Right Angles in a.s.sembling a Framed structure.]

To fit the drawer to its place, runners and guides, Fig. 295, must first be fastened in. The runners are in line with the drawer rail, and are glued and nailed or screwed to the side rails between the back of the lower stringer and the back posts. On top of them and in line with the inner face of the legs are the guides running between the front and back posts. Or the runner and guide may be made of one piece properly rabbeted out.