The joiner's hand operations necessary in producing common types of machine-made joinery are of a semi-skilled nature, involv ing little more than the cramping and wedging up of framing; even the final process of glass papering is frequently performed by ma chinery. Where there is a well equipped machine-shop highly skilled hand work is only required in the production of high class hard-wood joinery, and in connection with work of double curva ture, such as geometrical stairs and handrails, door and window frames that are curved in both plan and elevation, and in examples of joinery involving complex moulding intersections such as may occur in a moulded lantern light or an open roof. To set out and work these and other examples of geometrical wood-work, the joiner must have a sound knowledge of three dimensional geome try in addition to a high standard of manual dexterity.
The skill and adaptability of the joiner was of great service during the World War, for he proved to be capable of performing all the wood-work operations necessary in the production of air craf t, including propeller shaping, without any preliminary period of special training.
Of hinges, the variety termed butts are in general use for hang ing doors, and are so called from being fitted to the butt edge of the door. They should be of wrought metal, cast-iron butts being liable to snap should they sustain a shock. Lifting butts are made with a removable pin to enable the door to be removed and re placed without unscrewing. Rising butts have oblique joints which cause the door to rise and clear a thick carpet and yet make a close joint with the floor when shut. Hinges of brass or gun-metal are
used in special circumstances. Common forms of hinges used on ledged doors are the cross garnet and the strap. There are many varieties of spring hinges designed to bring the door automatically to a desired position.
Among locks and fastenings the ordinary barrel or tower bolt needs no description. The flush barrel is a bolt let in flush with the face of a door. The espagnolette is a development of the tower bolt and extends the whole height of the door; a handle at a con venient height, when turned, shoots the bolts at the top and bot tom simultaneously. Their chief use is for French casements. The padlock is used to secure doors by means of a staple and eye. The stock lock is a large rim lock with hard wood casing and is used for stables, church doors, etc. ; it is in the form of a dead lock opened only by a key, and is often used in conjunction with a Nor folk latch. The metal cased rim lock is a cheap form for domestic and general use. The use of a rim lock obviates the necessity of forming a mortise in the thickness of the door which is required when a mortise lock is used. The Yale lock is now generally used for every ordinary type of door. Finger plates add greatly to the good appearance of a door, and protect the painted work. Sash fasteners are fixed at the meeting rails of double hung sashes to prevent the window being opened from the outside and serve also to clip the two sashes tightly together. They should be of a pat tern to resist the attack of a knife inserted between the rails. Sash lifts and pulls of brass or bronze are fitted to large sashes. Orna mental casement stays and fasteners in many different metals are made in numerous designs and styles. Fanlight openers for single lights, or geared for a number of sashes, may be designed to suit positions difficult of access.