Page:EB1911 - Volume 15.djvu/504

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JOINERY
477

treats of the projection and description of lines, surfaces and solids, as well as an intimate knowledge of the structure and nature of wood. A man may be a good carpenter without being a joiner at all, but he cannot be a joiner without being competent, at least, to supervise all the operations required in carpentry. The rough labour of the carpenter renders him in some degree unfit to produce that accurate and neat workmanship which is expected from a modern joiner, but it is no less true that the habit of neatness and the great precision of the joiner make him a much slower workman than the man practised in works of carpentry. In carpentry framing owes its strength mainly to the form and position of its parts, but in joinery the strength of a frame depends to a larger extent upon the strength of the joinings. The importance of fitting the joints together as accurately as possible is therefore obvious. It is very desirable that a joiner shall be a quick workman, but it is still more so that he shall be a good one, and that he should join his materials with firmness and accuracy. It is also of the greatest importance that the work when thus put together shall be constructed of such sound and dry materials, and on such principles, that the whole shall bear the various changes of temperature and of moisture and dryness, so that the least possible shrinkage or swelling shall take place; but provision must be made so that, if swelling or shrinking does occur, no damage shall be done to the work.

In early times every part was rude, and jointed in the most artless manner. The first dawnings of the art of modern joinery appear in the thrones, stalls, pulpits and screens of early Gothic cathedrals and churches, but even in these it is indebted to the carver for everything that is worthy of regard. With the revival of classic art, however, great changes took place in every sort of construction. Forms began to be introduced in architecture which could not be executed at a moderate expense without the aid of new principles, and these principles were discovered and published by practical joiners. These authors, with their scanty geometrical knowledge, had but confused notions of these principles, and accordingly their descriptions are often obscure, and sometimes erroneous. The framed wainscot of small panels gave way to the large bolection moulded panelling. Doors which were formerly heavily framed and hung on massive posts or in jambs of cut stone, were now framed in light panels and hung in moulded dressings of wood. The scarcity of oak timber, and the expense of working it, subsequently led to the importation of fir timber from northern Europe, and this gradually superseded all other material save for special work.

Tools and Materials.—The joiner operates with saws, planes, chisels, gouges, hatchet, adze, gimlets and other boring instruments (aided and directed by chalked lines), gauges, squares, hammers, wallets, floor cramps and a great many other tools. His operations consist principally of sawing and planing in all their varieties, and of setting out and making joints of all kinds. There is likewise a great range of other operations—such as paring, gluing up, wedging, pinning, fixing, fitting and hanging—and many which depend on nailing and screwing, such as laying floors, boarding ceilings, wainscoting walls, bracketing, cradling, firring, and the like. In addition to the wood on which the joiner works, he requires also glue, white lead, nails, brads, screws and hinges, and accessorily he applies bolts, locks, bars and other fastenings, together with pulleys, lines, weights, holdfasts, wall hooks, &c. The joiner’s work for a house is for the most part prepared at the shop, where there should be convenience for doing everything in the best and readiest manner, so that little remains when the carcase is ready and the floors laid but to fit, fix and hang. The sashes, frames, doors, shutters, linings and soffits are all framed and put together, i.e. wedged up and cleaned off at the shop; the flooring is planed and prepared with rebated or grooved edges ready for laying, and the moulded work—the picture and dado rails, architraves, skirtings and panelling—is all got out at the shop. On a new building the joiner fits up a temporary workshop with benches, sawing stools and a stove for his glue pot. Here he adjusts the work for fitting up and makes any small portions that may still be required.

The preparation of joinery entirely by hand is now the exception—a fact due to the ever-increasing use of machines, which have remarkably shortened the time required to execute the ordinary operations. Various machines rapidly and perfectly execute planing and surfacing, mortising and moulding, leaving the craftsman merely to fit and glue up. Large quantities of machine-made flooring, window-frames and doors are now imported into England from Canada and the continent of Europe. The timber is grown near the place of manufacture, and this, coupled with the fact that labour at a low rate of wages is easily obtainable on the Continent, enables the cost of production to be kept very low.

The structure and properties of wood should be thoroughly understood by every joiner. The man who has made the nature of timber his study has always a decided advantage over those who have neglected this. Timber shrinks considerably in the width, but not appreciably in the length. Owing to this shrinkage certain joints and details, hereinafter described and illustrated, are in common use for the purpose of counteracting the bad effect this movement would otherwise have upon all joinery work.

The kinds of wood commonly employed in joinery are the different species of North European and North American pine, oak, teak and mahogany (see Timber). The greater part of English joiners’ work is executed in the northern pine exported from the Baltic countries. Hence the joiner obtains the planks, deals, battens and strips from which he shapes his work. The timber reaches the workman from the sawmills in a size convenient for the use he intends, considerable time and labour being saved in this way.

A log of timber sawn to a square section is termed a balk. In section it may range from 1 to 11/2 ft. square. Planks are formed by sawing the balk into sections from 11 to 18 in. wide and 3 to 6 in. thick, and the term deal is applied to sawn stuff 9 in. wide and 2 to 41/2 in. thick. Battens are boards running not more than 3 in. thick and 4 to 7 in. wide. A strip is not thicker than 11/2 in., the width being about 4 in.

Fig. 1.

Joints.—Side joints (fig. 1) are used for joining boards together edge to edge, and are widely employed in flooring. In the square joint the edges of the boards are carefully shot, the two edges to be joined brought together with glue applied hot, and the boards tightly clamped and left to dry, when the surface is cleaned off with the smoothing plane. A joint in general use for joining up boards for fascias, panels, linings, window-boards, and other work of a like nature is formed in a similar manner to the above, but with a cross-grained tongue inserted, thereby greatly strengthening the work at an otherwise naturally weak point. This is termed a cross-tongued and glued joint. The dowelled joint is a square glued joint strengthened with hard wood or iron dowels inserted in the edge of each board to a depth of about 3/4 in. and placed about 18 in. apart. The matched joint is shown in two forms, beaded and jointed. Matched boarding is frequently used as a less expensive substitute for panelled framing. Although of course in appearance it cannot compare with the latter, it has a somewhat ornamental appearance, and the moulded joints allow shrinkage to take place without detriment to the appearance of the work. The rebated joint is used in the meeting styles of casements and folding doors, and it is useful in excluding draughts and preventing observation through the joint.

Fig. 2.

Of the angle joints (fig. 2) in common use by the joiner the following are the most important. The mitre is shown in the drawing, and is so well known as to need little description. Although simple, it needs a practised and accurate hand for its proper execution. The common mitre is essentially weak unless reinforced with blocks glued into the angle at the back of it, and is therefore often strengthened with a feather of wood or iron. Other variations of the mitre are the mitre and butt, used where the pieces connected are of unequal thickness; the mitre and rebate, with a square section which facilitates nailing or screwing; the mitre rebate and feather, similar to the latter, with a feather giving additional strength to the joint; and the mitre groove and tongue, having a tongue worked on the material itself in place of the feather of the last-named joint. The last two methods