Part 12

To determine the position of the centre pin of the hinge the following rule is observed. The centre of the pivot pin of the hinge must be half the distance between the face of the door, when closed, and the outside of the architrave moulding.

CLOSE JOINT HANGING.--The method known as "close joint hanging" ensures the joint at the hanging stile being in close proximity to the hanging rail; this is shown at Fig. 249. The first member of the architrave moulding is generally a bead of the same diameter as the knuckle of the hinge. The butt hinge is let in as shown in the illustration, and the door when opened forms a close-fitting joint.

THE RULE JOINT HINGE is used to connect the top and the drop leaf of a table in cases where continuity of design is desired, so that the edge of the top and the leaf will show an ovolo moulding when the table is either open or closed. To the inexperienced worker it presents several difficulties and, if it is a first effort, it is advisable to try out a sample joint on a couple of odd pieces of timber.

Fig. 250 illustrates the joint when the leaf is opened or in a horizontal position. At Fig. 252 we have the joint when the leaf is let down to a vertical position. It should be observed in the latter figure that the edge A of the drop leaf is in alignment with the axis of the hinge. Steel or brass back-flap hinges (Fig. 233) are generally used and they are sunk into the table as suggested.

Set out the work full size as at Fig. 251, and mark point 1, which is to be the position of the joint. Draw 1, 2, at right angles to the table top. Mark point 3 on the vertical line for the centre of the hinge, and mark point 4 approximately as shown.

With compass point on 3 and radius 3 to 4, describe an arc 4 to 5. This gives us the true joint line (1, 4, 5). The distance 0 to 3 is usually determined by the hinge. The knuckle of the back flap hinge is always let into the under side of the wood and the further it is inserted into the wood the more the joint will overlap at A (Fig. 252) which shows the joint when the flap or leaf is down.

SHUTTING JOINTS

This chapter deals with the joint made by the upright rail of a door frame which carries the lock, or handle, generally called the "slamming stile." Many and varied are the methods used to make a draught and air-tight joint at the meeting of the slamming stile and the carcase end, and our sketches illustrate some of the simplest and also some of the best and most expensive methods.

Fig. 253 is a part plan of the end of a simple cupboard of which the carcase end is all of one thickness (i.e., not lined up in thickness). A small strip of wood (A) is glued and screwed on the end to form a stop to the door and to prevent the access of dust to the interior of the cupboard.

Fig. 254 illustrates a similar method; the stop (C) is seen, as in the previous illustration, but it will be noticed also that the carcase end in this case is lined up (see B) to give a pilaster-like appearance to the end, and the moulding is selected on account of its suitability to hide the joint of the lining piece.

Fig. 255 is of a more intricate type, and is often used on jewellers' showcases. The end at the right hand is slightly rebated to receive the frame, and both the rail and the end are grooved with a plough plane. A separate bead is made and glued into the groove of the door frame (D), engaging the groove in the carcase end when the door is closed. The shutting stile and the end are worked with a hook joint (E), and if carefully made they are practically dust-tight.

Fig. 256 shows the meeting of two doors which open outwards, a separate piece of timber being made to form a rebated astragal mould (F) and glued to the right-hand door. This method gives a neat and effective finish.

Fig. 257 is similar to the above, with the exception that the rail of the door is rebated (G) to receive the astragal moulding. This method is preferred on the best class of work, because it shows no unsightly joint at the inside of the door frame.

Fig. 258 illustrates the type of joint made by using a brass astragal mould (H) as employed on high-class work, frequently seen on French furniture of the Louis periods. In Fig. 259 is shown a piece of brass astragal moulding, which may be procured from any cabinetmaker's ironmonger in suitable lengths. It is fixed in position by slightly rebating the edge of the door and fastening with ordinary countersunk brass screws.

Fig. 260 is a rebated joint, broken at the front by a bead moulding. The illustration shows its application to a circular-fronted cupboard, and it will be noticed that the hinged rails are received in a rebate which is worked on the carcase ends. The rebated joint at the centre of the two doors is worked slightly on the bevel, so as to allow for clearance when opening the door.

Two of the commonest meeting joints of doors are seen in Figs. 261 and 262. In the former case the stiles are rebated (as already shown in Fig. 260), whilst at Fig. 262 an astragal bead is glued to the right-hand stile. In Fig. 261 a bead is worked on the right-hand stile to mask the joint.

Fig. 263 is the hook joint used on good-class joinery and cabinet work. A pair of special wood planes are required to make the joint in a cheap and efficient manner. The cost of a pair of 5/8-in. hook joint planes is from 6s. to 8s. They are of similar size and general appearance to the ordinary ovolo moulding plane.

Fig. 264 is a special type of hook joint as used on larger work. The joint may be made by using the plough plane, the rebate plane and a suitably-sized bead plane, the loose tongues being inserted as shown and fastened by screws and glue.

Fig. 265 is a rebated joint with loose tongue-slip and astragal mould, suitable for frames over 1-1/4 in. in thickness. The loose tongue-slip is glued into the right-hand door frame.

Fig. 266 shows a shutting joint used to prevent permeation of dust to the interior of a drawer. The drawer front is grooved and engages a suitably-formed slip which is screwed to the bearer as indicated in the illustration. Occasionally some difficulty is experienced when fitting the slip to a narrow drawer, but this can always be overcome by putting in the screws from the top of the bearer instead of from underneath.

Shutting joints which are required to be "light-tight," such as those used in photographic work, are generally formed by slightly grooving the frame and inserting a strip of black velvet. The friction of the high pile of the velvet prevents the filtration of light through the joint.

When making air-tight showcases, one of the best and simplest tests is to place a lighted candle in the case and close all the doors; if the candle goes out within three minutes you have accomplished your object.

THE DOVETAIL JOINT

Nothing definite is known as to the origin of dovetailing, but a quaint and pleasing little story which is well worth repeating runs as follows: A farmer had called in the local "joyner" to do sundry repairs at the homestead. One day, whilst enjoying a humble meal, he sat watching some doves as they hopped about the yard. Struck by the movement of their wedge-shaped tails, it occurred to him to joint his timber by the interlocking method; hence we have dovetails.

THROUGH DOVETAILING.--One of the simplest forms of the dovetail joint is shown in Fig. 267, where two pieces of timber are joined by the method known as "through" dovetailing. This method is used in everyday practice for joining the corners of frames, bracket trusses, and a hundred and one other articles.

Figs. 268 and 269 show the method of through dovetailing as applied to the making of boxes, plinths, and general carcase work; it is used in positions where no objection can be taken to the end grain showing on each side of the finished work. In the case of plinths and furniture cornices the foundation frame is made of yellow pine or other cheap wood, and the more expensive and rare timbers are glued and mitred around in various thicknesses and shapes, thus saving the more costly material and strengthening the construction by the method known as laminating. In many cases all that is necessary is to veneer the face sides, thus covering and hiding any unsightliness.

LAP-DOVETAILING.--Fig. 270 is an example of lap-dovetailing, such as is used where a drawer side joins with the drawer front. It is not permissible to allow the end grain of the timber to show at the front of a drawer, and this is why resort is had to the lap-dovetail. As the most general use of the dovetail is for this and similar purposes, we shall therefore deal fully with the methods of marking out and the making of this class of joint.

ANGLES.--A most important point in the construction of a dovetail is to avoid having the angles of the pins and tails too acute. An inclination of one in eight is considered correct; no hard and fast rule need be obeyed, but the variation should on no account be less than one in six.