Top back rail joints are illustrated in 466. Figure 466:1 is a tenon on the rail, 466:2 shows a tenon on the post, and 466:5 a dovetail bridle joint. Where the wood sections are very slim (466:6) the joint can be reinforced by forming a step to
466 Chair joints support the back thrust and increase the gluing area. Figure 466:3 shows a shaped post and top rail mortised and tenoned together and rounded after assembly. In 466:4 the top dowel has no real holding power but does prevent the top twisting out of line, while dowels are also used in 466:7 where it might be difficult to accommodate a tenon in the curve of the back post. The shield back chair in 466:8 and Chippendale carved chair in 466:9 are shown as a matter of interest only, for the heavy carving usually disguises the line of the joint, as shown by the dotted lines. A modern treatment in which a bowed, tilted and rounded back rail meets turned back posts is shown in 466:10-12, with 466:10A the front view and 466:10B the back view. Figures 466:11, 12 show the actual joint and the amount of material left on to accommodate the dovetail. The joint must be carefully laid out and worked with the final rounding and shaping done when the rail is fully assembled. This type of construction is very expensive, therefore, and confined to the best handwork only. Figure 466:13 shows a mortise and tenon joint at the junction of front and side seat rails with the front leg. Either a canted tenon or a canted mortise is necessary for the latter; therefore it is more usual to tenon the front rail and dowel the side rail (466:14), in which it is comparatively simple to bore the leg at the correct angle obtained from the full-size drawing. The outer face of the leg is usually planed off after assembly to the line of the rail, as indicated by the dotted lines in 466:13. Back seat rails are normally tenoned into the back posts. Where a rail meets a rounded leg (466:15) a small flat can be worked for square-cut tenon shoulders, but if the rail is also rounded then the leg recess must be scribed to fit. Here again it is simpler to use dowels, cutting the rail end square, marking and boring for the dowels and scribing the rail shoulders to fit the leg before the dowels are glued in (466:16). Figure 466:17 shows a turned spindle entering a round leg. and if a bung borer (taper bit) is available then the spindle is turned to fit the taper, taking care to ensure that the socket depth is correct, for there will be no shoulder to limit the entry. Parallel-sided sockets bored with standard bits will require a turned shoulder on the spindle and a small flat formed on the leg, but in cheap work the taper spindle is merely driven into the parallel hole, with the result that it only bites at the neck. In 466:19, where a pronounced hollow is formed in the leg, it will be easier to use dowels, marking, boring and then fitting the rail to the leg before the dowels are inserted. An improved method of jointing side rails to back posts sometimes adopted in Scandinavian furniture is shown in 467 but it is essentially a machine operation.
The junction of arm rests with leg posts is shown in 466:20 where a small stub tenon can be used, although a single dowel is often effective, for the strain is upwards and not sidewards. Traditional chairs with turned legs and flat arm rests employed a spigot end to the leg taken through and wedged from the top, as 466:22, while 466:21 is the jointing of a typical modern framework where the overall angle is halved and dowelled together. Figure 466:23 is the juction of arm post with side rails in conventional armchairs, with the arm post housed/grooved in and screwed from the inside, and 466:24 the connection with the back post with stub dowel to take the pull. Older examples were often housed in and screwed and pelleted from the back (466:25), while 466:26 is the junction of a downward curved arm rest tenoned in and housed at the top to avoid a feather edge in the final shaping after assembly.
467 Chair rail joint
468 Dining-chair details
469 Timeless dining chairs by Gordon Russell Ltd. first designed in 1953
The illustrations in 468 show the construction of this type of chair. Figure 468:1 is the side elevation; 468:2 the seat plan; 468:3 the angle of the rail joints taken from the full-size drawing. and 468:4 the heavy corner blocks which are glued and screwed into each corner of the seat frame to increase the overall rigidity of the chair. Figure 468:5 is an exploded diagram of the construction, with the front rail kept down flush with the rebates/rabbets in the side rails, with a supporting fillet screwed to the back rail for the plywood base of the seat. This plywood base should be bored to allow the air to escape from the foam-rubber seating, especially if impervious top coverings (leather, plastic cloth, etc.) are used. Figures 468:6. 7 are alternative mortise and tenon joints for front and back posts. The padded back is screwed to the back posts from the inside, and the top cover carried over to hide the framing, or alternatively 6 in (152 mm)-taper dovetail slide connectors can be obtained in which the female part is screwed to the back post, and the male part screwed to the back rest slid down into position after the upholstery is completed. Chairs of this description can have webbed and upholstered drop-in seats as shown later in this chapter, in which case the front rail is flush with the side rails and the 5/8 in (16 mm) rebate continued round to receive the seat frame. Figure 496, for example, shows a typical seat frame for webbing which can either be dowelled, or half lapped and screwed. Suitable dimensions for average seat frames can be 2 in (51 mm) or 2 1/2 in (63.5 mm) wide stuff, 5/8 in (16 mm) or 3/4 in (19 mm) thick, and are usually made of beech, which will take closely spaced tacks without splitting. There is usually a rebate in the chair rails, allowing about 1/8 in (3 mm) clearance all round for the thickness of the covering materials.
Traditional examples of this type of chair often used coppice ash for the back posts, which merely required soaking in hot water to enable the bend to be formed. It is usual to turn first and then bend, although there is always some danger of crushing the rounded surface of the wood if the bend is acute. Modern examples of these chairs are often stained with clear penetrating dyes which do not choke or disguise the grain of the wood, but to avoid uneven coloration the whole chair should be dipped.
The chairs by John Makepeace and Rupert Williamson illustrated on the following pages show clearly the work of the modern artist-craftsman. All four pieces are extremely complex feats of woodworking skill and are designed to be made without compromise. Production would be near impossible by machine production methods.
The pieces by John Makepeace are achieved partly by the careful laminating of thin strips cut from the same piece of timber, then numbered, so that when reassembled in the mould the joints are nearly invisible to the naked eye. Rupert Williamson employs more traditional forms of construction, but the skill and patience of the hand craftsman are clearly seen in these highly intricate backs.
In contrast, 476-478 show the work of craftsmen when they are not designing for a unique situation but for relatively inexpensive batch production. These chairs could possibly be mass-produced, but the fact is that they are not; they are all made to a very high standard within each craftsman's workshop.
471 Turned rush-seated chair
472 John Makepeace: chair in solid and laminated ebony with woven nickel seat and back
473 John Makepeace: part of a special commission in oak for dining table and chairs designed to reflect the surrounding woodland as seen from the dining
474 & 475 Rupert Williamson: dining chairs in sycamore with inlay and edging of rosewood
Richard La Trobe Bateman's chair (476) is ideally suitable for this form of workshop production, relying as it does on simple square-edged wood and machined joints. However, being a craftsman, he is not content with that, so the seat is carefully contoured to the body and those two harsh-looking back planks spring to provide unexpected comfort.
David Colwell (p. 468) uses steam bending and turning and low technology to produce his visually simple and appealing chairs which are made in considerable quantities for retail distribution.
Lucinda Leech's chaise longue and armchair, designed for garden, patio or conservatory, use a combination of simple square framed joinery and laminated construction so straightforward and cleverly designed that only one mould is used for each piece. For clarity, both pieces are illustrated here without the cushions designed to go with them (479 and 480).
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