Woodwork Joints | Page 3

nature. Jointed boards should always be glued up with the grain running in the same direction if possible; this we show at Fig. 13, and nothing looks worse than a dressing chest end or similar piece of work in which the grain runs haphazard. When jointing thin timber (say, 1/4-in., 3/8-in., 1/2-in. and 5/8-in. boards) the best method is to use a shooting board (Fig. 26). It must be noted, however, that a shooting board and plane practically never give a true right angle, owing to wear and the grinding of the blade. Therefore, the boards should not all be laid with the "face mark" on the shooting board whilst the edges are shot, because any inequality would be multiplied by the number of pieces jointed. A better method is to alternate the boards, face side up, then face side down, whilst shooting the edges; this will prevent convexity or concavity on the face of the jointed board, because any slight error in the angle is neutralised (see Fig. 8).
APPLICATIONS OF THE JOINT.--The following show various applications of the butt or glued joint:--
[Illustration: Fig. 14.--Carcase Wing-pieces Glued on.]
Fig. 7A shows a mahogany or other hardwood slip glued on the edge of a cheaper wood, such as pine or whitewood, as is the case on bookcase shelves when only the front edge is seen and polished.
Fig. 7B shows a moulding glued on a shelf, both mould and shelf in this instance being of polished hardwood. A shelf of this type might be used in a recess, the object of the overhanging moulding being to hide a small 3/8-in. iron rod which would carry the curtain rings and heading of the curtain which covers the recess. The shelf would be fixed about 3 ft. 9 ins. to 4 ft. 3 ins. from the floor.
Fig. 14 shows the wing pieces glued on the top bearer of carcase work. The application of this bearer in its position will be shown in the chapter on Dovetailing.
Fig. 15 shows a butt joint planed at an angle of 45 degrees (commonly called a mitre), used for box feet, etc.
Fig. 16 shows jointing up of an ogee-shaped panel. The dotted lines indicate the thickness of the timber previous to its being worked up to the finished shape. Bow-fronted and semicircular panels are jointed in a similar manner.
[Illustration: Fig. 15.--Butting Mitred Angle Joint.]
[Illustration: Fig. 16.--Jointing Ogee-shaped Panel.]
Fig. 17 shows timber jointed at right angles to the upright piece, and at an angle of 30 degrees.
Fig. 18 indicates quarter-circle jointing, as used in round-cornered chests of drawers, wardrobes, cupboards, etc.
Fig. 19 is similar to Fig. 18, but with hollow (or concave) corners.
[Illustration: Fig. 17.--Jointed Timber at 30° and 90° angles.]
[Illustration: Fig. 18 (above).--Convex Corner.]
[Illustration: Fig. 19 (below).--Concave Corner.]
[Illustration: Fig. 20.--Jointing a shaped Spandrel.]
[Illustration: Fig. 21.--Building up Case of Piano Front.]
[Illustration: Fig. 22.--Use of the Try-square for Testing Edge.]
[Illustration: Fig. 23.--Example of Circular Laminated work.]
[Illustration: Fig. 24.--Glueing Ploughslips to Drawer.]
[Illustration: Fig. 25.--Method of holding Glued Joints with Iron Dogs.]
[Illustration: Fig. 26.--Method of using Shooting Board.]
Fig. 20 gives us the jointing up of a shaped spandrel to the required width. In a case of this description suitably grained and coloured wood should be selected, otherwise the bad match will at once draw attention to the joint.
Fig. 21 shows the application of butt or glued jointing to the building up of the core of a piano fall previous to shaping up and veneering.
Fig. 23.--Laminated work--the building up of circular rims for cabinet and joinery work. Plan and elevation show rim pattern of a pulley as used in the pattern-making trade.
[Illustration: Fig. 27.--Cramping Glued Joints: Handscrews and Batten shown at left; temporary Batten at right to keep the wood flat.]
Fig. 24.--The glueing of a ploughslip to a drawer side is seen here, the ploughslip being used to carry the drawer bottom.
Fig. 26 shows the method of jointing with shooting board and trying plane; the right hand operates the plane whilst the left hand holds the wood firm upon the shooting board.
Owing to the importation of narrow and faulty timber the necessity of jointing is greater to-day than ever it was, wide timber of course meaning higher cost for raw material.
The method of using iron dogs is illustrated in Fig. 25, and it will be observed that owing to the wedge-like formation of each fang (see enlarged sketch) the dog exerts the necessary pressure to close the joint. At the centre of this illustration is suggested the home-made hardwood blocks, baseboard and wedges referred to on page 4.
Fig. 27 shows how the iron sash cramps are used to apply pressure to the joint. As this method is in some cases apt to bend and distort thin boards it is wise practice to fix (as a temporary measure) a stout piece of straight wood on to