Page:Cassells' Carpentry and Joinery.djvu/79

Rh them in addition to the end-long strain, while vertical struts have no cross strain to meet.

Jointing Beams to Posts and Struts.—The usual methods of forming joints between beams, posts, struts, and braces as used in the construction of gantries, stagings, jetties, bridges, etc., are illustrated by Figs. 238 to 254. The inscriptions to the illustrations make the methods quite clear to understand.

Edge Joints.—Eleven joints used in connecting boards edge to edge are shown by

Figs. 255 to 265. Matchboarding is thin stuff with a tongue and bead worked on one edge and a groove on the other, so that when the pieces are put together the joint is masked by the bead, and the tongue prevents dust and draught from passing through, as in Fig. 263. A slip feather is a piece of wood inserted in plough grooves, as in Fig. 260, to strengthen a glued joint, or to keep out the dust. It may be of soft wood, and is then in short lengths, made by cutting pieces 1 in. wide off the end of a plank, turning the pieces over, and cutting them into thin strips, with the grain across their length. If hard wood is used, the grain may run in the direction of the length. The slip feathers may also be double, or dovetailed.

Right Angle Joints.—Fourteen styles of angle joints are shown by Figs. 266 to 279.

Obtuse Angle Joints.—Four kinds of these joints are illustrated by Figs. 280 to 283.

Dovetail Joints.—These are known in great variety, but it will be sufficient to show a few kinds only: the ordinary