Fig. 92 - Mortise and Tenon.
In other joints of the same kind the tenon does not show at all when the joint is complete, and, needless to say, this is the neater form, though a little more troublesome. In it the tenon is shorter and smaller, being as shown by the dotted lines in Fig. 93. The mortise in this case cannot be made with a saw, but must be hollowed out with a chisel. If a wide opening, the mortise chisel should be used in preference to one of the thinner kind, which does for the sides.
For wide frames two tenons may be cut, as shown in Fig. 94, and what may be considered a shorter tenon left between them, or to reduce the size of a tenon either above or below it as in Fig. 95.
Fig. 93 - Another Form.
Fig. 94 - Double Tenon.
Fig. 95 - Tenon with haunch.
Fig. 96 - Tenons on End of Shelf, etc.
Such a short part is called the haunch, and is not often used in doors for furniture.
The tenon joint is often used for drawer bearers and fixed shelves. The tenons are then left the full thickness of the stuff, as seen in Fig. 96. One or more tenons may be used, according to the width of the piece, and the width of the tenons is dependent on similar considerations. Such tenons as these, of course, can seldom be allowed to appear through the wood, so care must be taken when cutting the mortises.
Tenons may be tightened up by wedging them. When they are cut through, this is simply done by driving in after the tenon is inserted, and, of course, is not practicable in such a tenon as that first described.
When the tenon is short and does not run through, it may be tightened as follows: - The end of the tenon is slightly split or cut, and one or more small wedges inserted. Their ends are left projecting, as in Fig. 97, so that on the tenon being driven home they are forced into it by the bottom of the mortise. It should be said that this method of fastening, or, as it is called, foxing, a tenon is seldom used in cabinet-making. A stub or stump tenon is often used in connexion with thin panelling and framework for backs, as well as other subsidiary parts. In such cases, to call the hollow for its reception a mortise is rather a misnomer, though for all practical purposes it is one. Instead of being cut with a chisel it is formed with the plough, and is really part of the grooving within which the panelling is placed. Though not a strong form of joint, it is sufficiently so for its purpose.
A tenon or tongue with corresponding mortise or hollow may be used in any part of cabinet construction wherever a joint of this kind, of which the principal types have been named, may seem advantageous.
The dowelled joint is preferred by many, and in most cases can be used instead of the mortise and tenon. In some it is simpler and more expeditious, these probably being the reasons why occasionally writers have objected to it. Dowelling frame work is a perfectly legitimate method, and may be practised without fear The relative merits of dowels and tenons I have no intention to discuss, for to do so would serve no good purpose. Both have their partisans, and any impartial man will admit that one form of joint is practically as good as the other. Some consider that one or other is neater, stronger, easier, quicker, or simply 'better.' All these points depend principally on what the worker has been most used to, for it is very easy to argue that dowels are better than tenons, and vice versa. The setting out or marking for dowelling follows the same rules as for dowelled straight joints - q. v.
Fig. 97 - Foxed Tenon.
Fig. 98 - Dowel-jointed Frame.
Fig. 99 - Halved Corner Joint.
In framing, two dowels should be used at each joint, one of which is represented on Fig. 98.
The halved joint is not infrequently used in making small cabinet doors and such-like parts, though it is hardly what one would expect to find in good work, and I do not think is ever employed in such. Still, as it answers fairly well, and is one of the least objectionable improvements (?) which are practised by cheap trade makers, it is not undeserving of notice. It is easily and quickly formed, and consists of nothing more than cutting away half the thickness from the two pieces to be joined, as seen in Fig. 99. The novice must again be cautioned about allowing for the width of the saw kerf. The joint must be glued and then secured by hand cramps till firm. Doors so made generally have the edges veneered to conceal the joints. Halving is also useful, and may with more propriety be employed on other parts than door frames, as when two pieces cross each other in light frame work on the backs of cabinets and overmantels. The joint then takes the form shown in Fig. 100.
Mitred joints for frames, etc, are occasionally required, and as it is seldom that much strength is required when such is the case, the halved joint does well enough sometimes. It is precisely similar to the others, except that the face is mitred, as shown in Fig 101. Mouldings on the edges of frames, it must be noted, are always mitred, for otherwise the members could not be got to coincide. It will be found that most joints are either those described, or are such slight modifications from them, that even the novice should have very little difficulty in constructing them whenever they may be necessary. This, however, will very seldom be the case, as those mentioned are sufficient for all purposes.
In the next chapter will be described various operations which are constantly met with.
Fig. 100 - Halved Joint.
Fig. 101 - Halved Mitred Joint.