It has become increasingly popular for doors, and the usual plan is to fix the ball to the door edge, and the striking plate to the cupboard. The plate usually has a projecting tongue, the purpose of which is to take the wear of the ball, and it is generally an advantage to bend this over slightly. It may be necessary to file it back slightly. A rather more satisfactory arrangement is to fix the ball to the cupboard, and the striking plate to the door edge. The entire fitting is thus invisible from the front. The method is practicable only when the wood in the cupboard is thick enough to take the ball casing. An alternative pattern of the ball catch and a magnetic catch.
There are many types of stays used for falls, tops, doors etc., and their purpose is either to support the part or to limit its movement. The simple straight form is generally used when there is plenty of room inside for its movement.
In a more restricted space the rule joint stay is the alternative. A special form of combined hinge and stay. When there are separate lopers the stay can be used to give automatic opening. It is, of course, necessary to cut slots through the writing top at the sides. For supporting lids such as those for cocktail and gramophone cabinets, an automatic stay is generally used.
The quadrant stay is often used for secretariat and similar falls.
Sliding door fittings
Sliding doors are widely employed in modern furniture, and various arrangements are used. For thin plywood doors the double groove system is the simplest. Note that the top grooves are double the depth of those at the bottom to enable the doors to be lifted up and dropped in. For thicker doors a fibre track with gliders is used. At the top a piece of hardwood can be let into the door back to act as a guide. It is screwed in position as at A after the door is in position. For glass doors a grooved track in either metal or plastic is useful.
Another method of dealing with thick sliding doors. Hardwood slips are let into grooves as shown, these being spliced in their length. One part of the slip is put in position, the door slid over it, and the remaining part of the slip added. The splice should be slightly to one side of the middle so that there is space for the door to be placed in position.
- Steel peg and collar castor.
- Orbital swivel castor.
- Peg and socket shelf fitting.
- Tonks strip for shelves.
A type frequently used for heavy items, like easy chairs, and settees is the orbit swivel type.
The peg-and-socket fixing is frequently used as it is only necessary to bore holes to receive the sockets. The bent metal loop is simply a friction fit needing only to be pushed in. An alternative is the Tonks strip. It is let into vertical grooves, and usually a second extra deep groove within the other is needed to enable the actual support to be inserted.
Screws and nails
Screws. Apart from being available in various metals and finishes: iron, brass, copper, japanned, plated and so on, screws are made in three chief forms: flat-head, round head and raised-head. In addition there is the Phillips screw which has a star-shaped recess in the head rather than a slot.
- Screw types. A countersunk; round head; raised head; Phillips.
- Types of nails. A oval wire nail; French nail; panel pin; veneer pin, cut brad.
Generally iron screws are used. They are stronger than brass, but they should be lubricated, partly to make them easier to drive, but mainly to prevent rust. ‘Vaseline’ or candle grease are both suitable. When brass screws are required it is better to drive in iron screws in the first place and then replace them with brass. Otherwise the resistance of driving into a new hole may cause the brass to break off. Countersunk or flat-head screws are mostly used in cabinet work, though there is a growing tendency to use the raised-head type in conjunction with screw cups for semi-show work, such as for fixing interior fitments.
Nails mostly used by the cabinet-maker: oval wire nails, used predominantly owing to their small neat head, and freedom from liability to split the grain; French nails used only occasionally; panel pins C the most widely used for medium work, they have a small head, easily punched out of sight; small cut brads handy when a nail with a stronger head grip is needed; veneer pins used for fine work, and occasionally needle points. The latter are of tempered steel and are usually snapped off after being driven in the required distance.
These are made chiefly to enable furniture to be made in sections for assembly at the retail shop or in the home. This is of particular advantage for export furniture, since space in transport is reduced to a minimum. Furthermore it simplifies polishing problems since awkward corners and the like are reduced to a minimum. Another way in fittings are invaluable is in the manufacture of fitments, shop furniture and so on. These are often large, and it is convenient to assemble the parts on the site.
There is a wide variety of fittings, and the work has to be designed to enable them to be used. There is no definite application, but generally their purpose is to enable carcase parts to be held together at right angles or in line with each other, or for fixing legs. Some of the fittings. That at A is used when there is no objection to the screw heads and cups appearing at the outside. It is often used for collapsible cots. That at B is for fixing parts together at right angles: it might be the sides of a cabinet to the back, or the sides to the top and bottom.
Round head screws are employed, these being driven in so that the plate can just move beneath the head. That for the parallel slot is in the middle of the slot; the other is centred in its slot at the round hole end. The plate is slipped into place, and is tapped down with a punch bearing on the projecting lug. It draws the parts together and when right home the screws are finally tightened. There is a tendency to draw the part over out of right angles, and it is therefore assumed that both ends are being treated alike, and that there is a corresponding member at front or back (top or bottom) which holds the parts at right angles. It is an advantage when the one part can fit in a shallow rebate or groove, as this ensures exact position. A similar idea but for parts in a straight line.
A device using an eccentric tongue. The main body is let into the edge of the one piece, much as a mortise lock is let in, and a hole bored at the side to enable a screwdriver or key to be inserted. The other small shaped member is let into and screwed to the other part. Thus, when the parts are put together the eccentric hook can be turned by inserting a screwdriver through the hole in the side so engaging with the shaped member.
The plastic fitting is used to join parts at right angles. Apart from its use a: a knock-down fitting it is often used for permanent work to avoid work joints such as dovetails. Another fitting for the same purpose, but here a bolt tightened with a tommy bar engages with a small plate let into the other part. The device is for fixing table legs. The angle pieces engage in slots in the leg and are screwed. Screws are used to fix the parts with the lugs, the latter passing through slots in the angled pieces. Finally the wedges are tapped in, forcing the legs beneath the top.