The sheathing is sometimes put on vertically or horizontally, but a much stronger door is obtained if it is put on diagonally. It is possible, indeed, to make a satisfactory door by the use of sheath ing alone, without any frame. The sheathing is put together in two thicknesses, and diagonally, but each thickness is made diagonal in the opposite direction_to the other thickness so that all the pieces cross each other. Such a door is shown in Fig. 347. In Fig. 348 is shown a door with diagonal sheathing on the outside of a frame work. Fig. 349 shows a strong type of door with a braced frame which is covered on one or both sides with vertical sheathing.
There is no difficulty in fastening together the simple doors just described, but when we come to the paneled doors, there are some special methods in use for fastening the rails into the stiles at the corners, which must be described. There are also special ways of building up the members of which the doors are composed, to prevent warping and twisting.
In Fig. 350 is shown the most simple type of door for use in the interior of a building. It is called a "four-panel" door on account of the arrangement of the panels and their number. The stiles, marked in the figure, are all made not less than 41 inches in width. The middle rail, marked 13, is made S inches wide, and the top rail C the same as the stiles. The bottom rail, marked D, is made wider also, its width being about 10 inches. The panels are marked EE.
Figs. 351 and 352 show other arrangements of panels which may be employed, but the sizes are all the same as in Fig. 350. Of course, the more cross rails there are between the top rail and the bottom rail, the stronger will be the door.
The point of greatest interest in the construction of a door is the joint between the top rail C and the stiles A A. The rail is always tenoned into the stiles, the stiles continuing all the way up to the top edge of the door, and this joint is never made as a mmtered joint. Fig. 353 shows the tenon by dotted lines.
It will be seen that it does not go all the way through the stile of the door but should be stopped back about z inch, so as not to show on the edge of the door.
Fig. 354 shows how a door should be constructed, the figure being a section taken through the stile of the door. The entire piece is built up out of strips of pines inch thick, and of a width equal to the thickness of the door, minus z inch for a veneering of inch thick on each side of the door. These strips arc carefully glued together, side by side, thus forming the finished piece on which the veneering is applied. Fig. 354 also shows the proper construction of a panel at the place where it joins the stile or the rail.
A piece marked A in the figure is first glued into the stile or rail, and to this are glued the panel moldings, after the panel has been put in place, the panel moldings projecting out beyond the piece A far enough to hold the panel, which is thus left free to move as it shrinks or swells. The panel will remain as a plain surface, and will not bulge or crack. The moldings should never be fastened in any way to the panel itself. Unless the panel is absolutely free to move it is sure to crack badly,