Transcriber's Note:
The Table of Contents has been changed to match the actual chapter headings.
A few hyphenations have been changed to make them consistent.
Minor typographic errors have been corrected.

WOODWORK JOINTS

(THE WOODWORKER SERIES)

REVISED EDITION

WOODWORK
JOINTS

HOW THEY ARE SET OUT, HOW MADE AND
WHERE USED; WITH FOUR HUNDRED
ILLUSTRATIONS AND INDEX

REVISED EDITION

LONDON

EVANS BROTHERS, LIMITED

MONTAGUE HOUSE, RUSSELL SQUARE, W.C.1

THE
WOODWORKER SERIES

EVANS BROTHERS, LIMITED,
MONTAGUE HOUSE, RUSSELL SQUARE,
LONDON, W.C.1.

EDITORIAL FOREWORD

To be successful in woodwork construction the possession of two secrets is essential—to know the right joint to use, and to know how to make that joint in the right way. The woodwork structure or the piece of cabinet-work that endures is the one on which skilful hands have combined to carry out what the constructive mind planned. And it is just here that the present Volume will help, not alone the beginner who wishes preliminary instruction, but also the expert who desires guidance over ground hitherto unexplored by him.

In the preparation of this new edition the Publishers have secured the services of Mr. William Fairham, by whom the chapters have been carefully revised and re-illustrated. Although intended for the practical man, and not professing to be a graded course of "educational woodwork," the Volume is one which Handicraft Instructors will find of the greatest value in conducting woodwork classes. No book hitherto published contains such a variety of illustrations of joints, almost all of which will form suitable exercises of practical educational importance in a woodworking course.

J. C. S. B.

Old Oak Chests, showing the Method of Structure which forms the origin of most of our English Furniture.
(From The Woodworker, January, 1927.)

CONTENTS

Staircase of the Second Half of Seventeenth Century.
(From The Woodworker, September, 1929.)

THE GLUED JOINT

The glued joint in its various forms is in use in every country in the world, and is frequently met with in mummy cases and other examples of ancient woodwork. Alternative names under which it is known are the butt joint, the rubbed joint, the slipped joint, whilst in certain localities it is known as the slaped (pronounced slayped) joint.

Fig. 1.—Simplest Form of Glued or Rubbed Joint.

The glued joint is made by planing two pieces of timber so that when placed together they are in contact with each other at every point; they are then usually united with glue. [Fig. 1] shows a sketch of a butt joint in its simplest form. In [Fig. 2] is indicated the method of holding the joint whilst being glued; the upright portion is held rigid in the bench vice, thus leaving the left hand to hold the piece which is to be jointed, whilst the right hand operates the glue brush. The pieces of wood which form a butt joint may be glued together with or without the aid of cramps or artificial pressure. If the joint is to be made without cramping, the two surfaces of the timber are warmed so as not to chill the glue. The surfaces are then glued and put together and rubbed backwards and forwards so as to get rid of the superfluous glue. They are then put aside to dry.

Glueing.—The better the glue penetrates into the pores of the wood, the stronger the joint will be; for this reason timber of the loose-fibred variety, such as pine, etc., will hold up at the joint better than hardwoods like teak and rosewood. The glue used for jointing should be neither too thick nor too thin; the consistency of cream will be found suitable for most purposes. It should be nice and hot, and be rapidly spread over the surface of the wood.

Fig. 2.—How the Wood is held whilst Glueing.

If light-coloured woods, such as pine, satinwood, sycamore, etc., have to be jointed, a little flake white should be procured and mixed into the liquid glue. This will prevent the glue showing a thin black line on the joint.

Broad surfaces of close-grained hardwood having a shiny surface are usually carefully roughened with a fine toothing plane blade previous to glueing.

Supporting the Joint.—The jointed boards should not be reared up against a "bench leg" or wall without having any support in the centre, as dotted line at [Fig. 5], because in all probability they will fracture before the glue has time to set; and, when we go to take them up to renew working operations, we shall be annoyed to find that they have assumed a position similar to that at [Fig. 5] (shown exaggerated), and this will, of course, necessitate re-jointing.

A correct method to adopt is seen at [Fig. 6]. Here we have supported the joint by rearing up against the wall a couple of pieces of batten, one at each end of the board, thus supporting it throughout its entire width until the glue is thoroughly set. The two or more pieces of timber in a butt joint adhere by crystallisation of the glue and atmospheric pressure. A well-fitted joint made with good quality glue is so strong that, when boards of 3 feet and upwards are jointed together by this method, the timber in most cases will break with the grain sooner than part at the joint.

Butt joints may be cramped up, if desired, and it is customary to warm them as previously stated. In the absence of the usual iron cramp, the amateur may make an excellent wooden arrangement out of any odd pieces of timber that happen to be handy. Two blocks of hardwood are screwed on the base board at a suitable distance for the work in hand; the boards to be jointed are glued and placed in position between the blocks; and the two hardwood wedges are inserted and hammered in opposite directions to each other, thus exerting the desired pressure. An example of this method of cramping is shown in [Fig. 25], which also indicates the use of iron "dogs."

When jointing, care should be taken to first plane up the boards true on one side—i.e., take them out of winding. The method of testing for this is shown at [Fig. 9], and it may with advantage be used when jointing the edges of the boards. Two laths or strips of wood are planed up to exactly the same width, having their edges straight and parallel. One edge of each lath may, if desired, be bevelled a little. The method of using these "twist sticks" or "winding laths" is to put them on the board as indicated, and sight along their top edges. The winding laths, being much longer than the width of the board, show up the irregularity greatly pronounced.

The Tools generally used for making the butt joints are:—

The jack plane, for roughing the edges, etc.

The wooden trying plane (or iron jointing plane) for trueing up the work.

The try square for testing purposes.

The winding laths and straight edge.

The Method of Work is as follows: Each board is in turn put in the vice and planed straight lengthwise; it is then tested with winding laths and a try square (the latter method is shown at [Fig. 22]).

Fig. 9.—Testing Surface with Winding Laths.

The boards are then put on the top of one another as at [Fig. 1] and tested with a straight edge; they should appear true as shown at [Fig. 3]; if they show faulty as at [Fig. 4] the joints must be again fitted until the required degree of accuracy is obtained. Difficulties may be avoided by care in selecting timber suitable for jointing, and it must be remembered that timber shrinks circumferentially (the heart side becoming curved) as dotted lines in [Fig. 10]. If the timber be jointed with all the heart side one way as at [Fig. 10], the tendency will be for it to cast as shown by the dotted line. If the timber be alternated as at [Fig. 11], the tendency will be to cast wavy, whereas if quartered timber can be obtained it will stand practically straight as the tendency to shrink is in thickness only. The grain of quartered timber is shown in [Fig. 12].

Fig. 10.—Showing Heart side of Timber one way.

Fig. 13.—Boards showing uniformity of Grain.

Judgment should also be exercised to avoid jointing in which one piece of timber is wild and large in the grain, and the adjoining piece of a mild-grained 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:—

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.

Fig. 15.—Butting Mitred Angle Joint.

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.

Fig. 23.—Example of Circular Laminated work.

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.

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 the board to be joined by using two handscrews as shown at the left hand of the illustration. At the right hand of the sketch a wooden cramping arrangement of the box type is given, and by wedging up the boards are closed together. It is obvious that if this type of box cramp be used it will prevent the boards buckling and the handscrew method at the left may be dispensed with.

THE HALVED JOINT

T he halved joint is frequently known as half-lapping, and sometimes as checking and half-checking. In the majority of cases it is made by halving the two pieces, i.e., by cutting half the depth of the wood away. There are, however, exceptions to this rule, as in the case of "three-piece halving" (or, as it is sometimes called, "third lapping") and in the halving of timber with rebated or moulded edges. Halving is one of the simplest methods of connecting two pieces of timber, especially where it is desired to make frames and bracket supports for either inside or outside use.

Fig. 28.—Frame, with various halved joints. These joints, numbered 1, 2, 3, etc., are shown in detail in Figs. 29 to 38.

[Fig. 28] shows the elevation of an imaginary frame which is indicated as made up of a number of halving joints; it shows also the application of the various joints to this class of work. Each joint used in the construction of this frame may be dealt with separately. The numbers marked on [Fig. 28] refer to the individual joints, shown separately in Figs. 29 to 38.

[Fig. 29] shows the "Halved Joint" at the corner of the frame where the two pieces form a right angle (see [Fig. 28, 1]). Each piece is halved and shouldered at opposite sides, thus forming a perfect fit one with the other and giving a strong joint with a minimum amount of labour. For inside work the joint would be glued and screwed together, the screw heads being countersunk so as not to come in contact with the cutting iron of the plane when levelling off the work. For outside work, in exposed positions where the work will have to withstand the weather, the alternative method of smearing the joint with paint or with a mixture of varnish and white lead would be advisable, the joint being nailed or screwed. [Fig. 29] shows the two pieces separated.

[Fig. 30] shows a similar joint to the above, but in this case the top rail runs through and it is generally spoken of as a "Halved T Joint" ([Fig. 28, 2]). It may be used in nearly all cases where a top or bottom rail runs through an upright. The method of securing the joint is as before. [Fig. 30] shows a sketch of the joint separated.

At [Fig. 31] is shown an "Oblique Halving Joint," where the oblique piece, or strut, does not run through ([Fig. 28, 3]). This type of joint is used for strengthening framings and shelf brackets; an example of the latter is shown at[ Fig. 48]. A strut or rail of this type prevents movement or distortion to a frame diagonally (generally spoken of in the trade as "racking"). [Fig. 31] shows the joint apart.

[Fig. 32] is an example of Oblique Halving with the upper piece running through ([Fig. 28, 4]). This joint is used in similar positions to [Fig. 31], and has in some cases the disadvantage of showing end grain at the top of the frame. The sketch shows the two pieces separated.

[Fig. 33] is "Dovetail Halving," the dovetail running through the top piece ([Fig. 28, 5]). This is a strong joint, used where outside strain is likely to occur in the top piece, the dovetail preventing the rail from being drawn away from the shoulder. The two pieces are shown separate.

At [Fig. 34] is seen "Mitred Halving," a somewhat weak joint, but necessary in mirror frames, etc., where good appearance is required on the face side ([Fig. 28, 6]). Its use is obvious if the face of the frame be moulded with beads or other sections which require to intersect one with the other. This also applies if the frame be moulded on its face edges.

[Fig. 35] is a halved joint with one side of the piece dovetailed ([Fig. 28, 8]). This joint is used in similar positions to [Fig. 33], and rather less labour is required in the making. The two pieces are shown separate for clearness.

[Fig. 36] indicates the "Halved Joint," the pieces at one end showing a double dovetail ([Fig. 28, 7]). This particular joint is seldom used except for Manual Training purposes. The illustration shows a sketch of the joint apart.

[Fig. 37] is "Oblique Dovetail Halving," one side of the piece being dovetailed. The joint is used to prevent "racking," and as a cross brace to framing. It is occasionally made with both its sides dovetailed as shown at [Fig. 33]. (For reference, see [Fig. 28, 9]).

[Fig. 38] shows "Stopped Dovetail Halving." In this case the dovetail is similar to [Fig. 33], with the exception that it does not run through the bottom rail. This is an advantage if the bottom edge of the rail is in evidence, or if it is required to glue a moulding or hardwood facing slip on the lower edge. The glue adheres better with the grain than it would end way of the grain, and if slight shrinkage occurs across the width of the bottom rail the moulding would not be forced away by the upright (see example at [Fig. 28, 10]).

Fig. 41.—Tee Halving Joint.

The joint lettered B in [Fig. 28] is a "Cross Halving Joint" where each piece runs through the other. [Fig. 39] shows this joint separated, and [Fig. 40] shows a similar joint separated where the joint is made edgeways.

[Fig. 41] shows a "Tee Halving Joint" with a dovetail cut on the edge. This is seldom used except as a woodwork exercise.

[Fig. 42] is a "Dovetailed Halving Joint" used for lengthening timber, and is also a favourite Manual Training model. It might also come under the heading of scarf joint, although rarely used in actual practice as such. As a practical woodwork exercise it calls for accurate marking out and careful fitting.

Fig. 42.—Dovetailed Halving Joint used for Lengthening Timber.

[Fig. 43] shows a combination of a halved joint dovetailed edgeways, whilst [Fig. 44] shows a dovetailed halved joint with the shoulders housed. This latter is seldom used in actual work.

At [Fig. 45] we have the application of halving joints when constructing a barrow wheel. The centre portion is an example of three pieces half-lapped or, as it is sometimes called, one-third lapped. A sketch of the three pieces separated is shown at L, B, C, [Fig. 46].

This joint is extensively used in the pattern making trade for lap-jointing the arms of pulley patterns, etc. It is probably the most difficult of the halving joints to mark out and construct with the desired degree of accuracy.

[Fig. 47] shows a combination of a bevelled dovetail half-lapped joint. This is only used as a puzzle joint. When neatly constructed and glued together it is apparently impossible to make it, showing as it does a half lap on one side and a dovetailed half lap on the reverse side.

[Fig. 48] is the end view of a kitchen table with drop leaf, showing the skirting board scribed to the solid side. A table of this type is fastened to the wall with two iron holdfasts which engage the ends of the table.

Figs. 49 and 50.—Separate pieces of Halved Moulded Joint.

Fig. 51.—Oblique Cross Halving Joint.

The hinged bracket frame shows the application of the halving joint to bracket supports for this and similar purposes, such as brackets to support shelving, etc. In this example the hinged brackets turn underneath the table top, and allow the leaf to drop out of the way when not required. The dotted lines show the position of a shelf for boots and shoes.

Fig. 54.—Carpentry Tie Joint.

[Figs. 49 and 50] indicate the halving of cross pieces which have their edges moulded; the pieces are shown separately, the moulding being omitted to give a clearer representation of the method of construction.

[Fig. 51] is an "Oblique Cross Halving Joint" where the two pieces are not at right angles. A plan and elevation of the joint are shown at the left, whilst a sketch of one piece of the joint is given in the right-hand illustration.

[Figs. 52 and 53] are principally used as Manual Training models, and call for patience and manual dexterity.

[Fig. 54] is used in carpentry and joinery where a tie or cross piece ties joists or beams at an angle.

[Fig. 55] shows the elevation and end view of a "Cross Halving Joint" with housed or notched shoulders. This joint is seldom used in actual practice. The separate parts are given in [Fig. 56].

At [Fig. 57] are shown two cross rails and an upright halved together. This type of joint is used where three pieces meet, as is the case in building the framing of a poultry house. The joint is nailed together.

Fig. 59.—Cellarette Partition Joints.

[Fig. 58] is the end view of an ordinary workshop trestle, showing the application of dovetailed halving where the legs have a tendency to strain outwards. The inset sketch of joint shows the housing of the top rail to receive the legs.

[Fig. 59] shows a deep drawer, generally known as a cellarette, and used in a sideboard to accommodate wine bottles. Here we have a good example of halving the cross pieces so as to form compartments. The part shown separately illustrates the method of construction. The ends of these pieces engage the housings or grooves of the drawer sides. Pigeon holes or compartments in stationery cases, bookcases and writing bureaux are constructed in a similar manner, although the method of housing, or combined halving and housing, is to be preferred in some cases.

Fig. 60.—Joint used for Table with Circular Top or Rim.

At [Fig. 60] is the plan of a circular table having a small circular shelf with the top removed. The rims or framing are built by the method known as laminating (see [Fig. 23] in chapter on the The Glued Joint), after which they are veneered on the face sides. The application of the halving joint to the shaped bottom rails, which in this case carry and support the small shelf, is shown in the part elevation.

Fig. 61 (A).—Oxford Frame with Halved Joints. (Four alternative corner treatments are given.)

[Fig. 61 (A)] shows the well-known "Oxford frame," illustrating halved joints when the edge is rebated. [Figs. 61 (B) and 61 (C)] make clear the construction of this type of joint. Alternative suggestions are shown for the treatment of the corners, the simple inlay being black and white (ebony and holly or boxwood). Frames of this type are made in various widths and sizes and are used for pictures, mirrors, etc.

Fig. 62.—The Two Pieces of a Halved Joint.

The tools used for making joints of the above class are: planes, the gauge, tenon or other saw, chisels, try square, and in some cases a joiner's bevel to obtain and mark the necessary angles, pencil and marking knife.

Plane up the face side and face edge of the timber, gauge and plane to both thickness and width; mark shoulders with pencil or marking knife; gauge to the thickness of the required halving; saw waste portions away; pare up with chisel to a good fit; glue or glue and screw, or use paint as previously mentioned, and then level off the surfaces.

Setting out the Halved Joint.—Although at first sight the halved joint may appear to be a very easy item of construction, it requires much care and attention in marking out and sawing. [Fig. 62] shows the two pieces which form the joint separated, and it will be noticed that each piece of wood has half its thickness cut away, so as to accommodate the other piece. This type of joint is used where two pieces of wood cross each other at right angles, or at an angle as shown in [Fig. 51]. The halving joint is used also for joining two pieces of wood at their ends, as, for instance, the corner of a frame, one half of this joint being shown at [Fig. 65 (B)].

Fig. 63.—How the Timber is Marked.

Fig. 64.—Marking the Joint with Try Square.

To make the joint, the timber should be carefully planed to its exact width and thickness. The two pieces may then be placed upon the bench (as shown at [Fig. 63]) or fixed in the vice.

Find the centre of the timber, C, [Fig. 63], and set out half the width of the wood on each side of the dotted centre line. Thus, suppose the wood (W) to be 2 ins. wide, then set 1 in. on each side of the centre line. Take a square as at [Fig. 64], and with a sharp penknife blade score or cut a line all round each piece of timber.

Fig. 65.—Using the Marking Gauge.

Next take up a marking gauge, and set the marking point to half the thickness of the wood. The distance may be measured, and its exactness tested, by pricking a small hole from each side of the wood with the marking gauge and carefully noting that the pricked holes coincide. The gauge mark is clearly shown in the various illustrations. Now, take a pencil and scribble or mark "waste" on the parts you intend to cut away. This will save trouble later on, especially if you are making several joints at once. Take your sharp penknife or marking knife blade, and cut fairly deeply into the marked line on the portion you are going to pare away.

Fig. 66.—Chiselling away Wood up to Gauge Line.

Fig. 67.—How work is held when Sawing Shoulder.

Fix the wood firmly in your vice, or against your cutting board or bench stop, as may be more convenient to you, and with a sharp chisel cut away the wood up to the marked line, as at [Fig. 66]. The channel in the sketch is exaggerated, so as to show the method clearly. The object of using a penknife or marking knife to mark your work, instead of using a pencil, will be obvious. Owing to the knife having scored about 1⁄16 in. deep across the fibres of the wood, the timber will come away cleanly when the chisel is used, as at [Fig. 66]. The small channel thus made will form a guide in which to start your tenon or dovetail saw; it prevents the saw cutting on the wrong side of the marked line and thus making the halving too wide.

Fig. 68.—Paring away Waste with Chisel.

Fig. 69.—Showing an Oblique Halved Joint.

Sawing.—Lay the work on the cutting board as at [Fig. 67]; or, if you prefer, put the work in the vice. Carefully saw down the work until you just touch the gauge line. Do not press heavily with the saw; use it lightly; the weight of the back iron which is fixed on the saw will ensure the saw feeding into the work quite fast enough. If the saw is newly sharpened it will, in fact, be an advantage to slightly ease the weight of the saw from off the wood, owing to the keenness of its edge. If the halving is a very wide one, additional cuts may be sawn between the outside marks, and these will greatly facilitate the removal of the waste wood when paring it away. For sawing the joint reference may be made to the chapter on [Dovetailing].

Fig. 70.—Sawing the Cheek of a Halving Joint.

Paring away the waste material with a chisel is the next step, and this is shown at [Fig. 68]. The work may be chiselled either in a vertical or a horizontal position. The horizontal position is the easiest for the amateur who has a vice or handscrew, because he may hold the work securely with a mechanical device and so avoid the unnecessary risk to his fingers.

Take the chisel and cut away A, [Fig. 68]; now turn the chisel and cut away B; after which keep the chisel horizontal and cut off "the top of the hill," as it were, C. Repeat the three operations until you gradually pare the wood away exactly to the gauge line. When chiselling, if you find a tendency for the work to chip or crumble at the back edge owing to the forward pressure of the chisel, turn your wood round and begin to cut from the other edge, allowing the chisel to finish paring at the centre.

Joints Other than a Right Angle.—If the halving joint is at an angle similar to the sketch shown at [Fig. 69], great care will have to be exercised in the use of the chisel, owing to the change in the direction of the grain of the wood. The arrow marks in this sketch distinctly indicate the direction in which the chiselling must be done so as to give a smooth result. This change of direction for cutting also applies to the bottom of the halving joint.

Cutting Joint at End of Timber ([Fig. 70]).—Should the halving joint be used at the end of a piece of wood, as at [Fig. 30], the waste material may be roughly sawn away and the flat surface trimmed up with a chisel.

To saw out this type of halving joint, proceed to work the shoulder line as already described; then place the piece of wood obliquely in the vice as shown ([Fig. 70]) and proceed to saw down the vertical line, carefully watching the gauge line to see that you saw on the waste side of the lines. Then turn the piece of timber with its opposite edge towards you, and again use the saw as illustrated. You will this time only have to watch the gauge mark on the edge of the wood, because the saw will readily follow in the saw kerf already made. Now place the wood vertically in the vice, and keeping the saw in a horizontal position, saw down to the shoulder line.

Halving joints properly made and fitted should knock together with the weight of the clenched fist; the use of a heavy mallet or hammer will deface the work.

Fig. 71.—Joints used in the erection of a Queen Post Roof Truss.

THE BRIDLE JOINT

A bridle joint is often defined as the reverse of a mortise and tenon, and is chiefly used in the carpentry and joinery trades. The name probably originated from the fact that it bears some resemblance to the manner in which a bit slips into the horse's mouth and is fastened to the bridle. There are fewer varieties of the bridle joint than of the halved or the mortise and tenon; and this being the case we may take the opportunity of giving a few detailed directions, with explanatory illustrations, on the setting out and the making.

Fig. 72.—Simple Bridle Joint.

[Fig. 72] shows a bridle joint in what is perhaps its simplest form, the separate pieces being given at the left and the completed joint at the right. A joint of this type may be applied in nearly all cases where a halved or a mortise and tenon joint could be used. Bridle joints have an advantage as regards appearance over the mortise and tenoned variety in cases such as [Fig. 73], which shows an occasional table leg fitted to the circular top framing. The bridle joint here allows the grain of the leg to run through to the top, and gives a better and more workmanlike appearance to the completed article.

Fig. 73.—Table Leg Bridle-jointed to Rail.

[Fig. 74] is a "Mitred bridle joint," the part a showing the upright portion separated. This is a most useful joint for positions similar to that shown in the small glass frame, [Fig. 75]. The wood framing in this case is only 13⁄8 in. in width, and if a mortise were used it would have to be exceptionally small. The shaped rail at the bottom of this frame again shows the application of the bridle joint.

[Fig. 76] shows an "Oblique bridle joint," used in many instances as a brace, or strut, to prevent framing from racking. (See also [Figs. 31 and 32].)

[Fig. 77] is a "Stopped bridle joint," used in positions where the top or bottom edge of the work meets the eye, and where, if the rail were allowed to run through, the end grain would appear unsightly.

[Fig. 78] is a so-called bridle-joint at the corner of a frame. This is also called an "Open slot mortise and tenon joint," a good strong, serviceable joint which can be used instead of the closed mortise and tenon type, its advantage being that less labour is required in the making. (See also [Fig. 169].)

[Fig. 79] is an "Oblique angle bridle joint," used in similar positions to the above, but when the two pieces meet at an acute angle at the end of a frame.

[Fig. 80] shows the application of the bridle joint to a roof truss. Two sketches are shown at the joining of the tie beam and the principal rafter. The joint a is the type generally used. (See also [Fig. 71] for the joints in a queen post roof.)

Fig. 80.—Application of Bridle Joint to Roof Truss.

Setting Out and Marking.—It is a safe rule, when setting out a bridle joint, to divide the thickness of the timber into three equal parts. This will leave the timber on each side of the tongue equal to the thickness of the tongue, thus giving uniform strength to the joint. The bridle joint is chiefly used for connecting the internal parts of wooden frames. It is stronger than the halving joint, and, owing to its peculiar construction, requires little in the way of pegs, screws or nails to secure it in position. [Fig. 81] illustrates the joint, both open and closed.

To understand the method of setting out and marking, glance at the sketch, [Fig. 81]. It is not necessary that the bridle piece A be the same width as the cross piece B; but it must be remembered when setting out the joint with the marking knife or pencil that the width marked W on piece B must be equal to the width W on the piece A. The timber should be fairly accurately sawn or planed to the same thickness, and all edges should be square and true.

The wood is placed upon the bench, and the joint marked out by using a marking knife or penknife blade and the try square. A knife blade is much better than a pencil, as the sharp edge severs the fibres of the wood and gives a finer line than the pencil. It is not always necessary to exactly square and trim the end of piece A; it may with advantage in many cases be left at least 1⁄4 in. longer than necessary and levelled off with the saw, plane and chisel after the joint is put together. (See Method of Cutting in [Fig. 92], page 47.)

When the piece A has to have a bridle joint fitted at each end, it is customary to cut the timber about 3⁄8 in. longer than necessary, and mark the shoulder lines C to the exact length, after which the joints are cut. This leaves the ends standing over the horizontal rails, and, after fixing the complete frame together, the small projecting ends are levelled off flush with the cross rails.

Gauging.—After squaring all the shoulder lines round the timber with the knife and try square, the mortise gauge should be set so as to strike the two gauge lines marked G, [Figs. 83 and 84], at one operation. If the worker does not possess a mortise gauge the lines may be marked at two distinct operations with the aid of the marking gauge ([Fig. 82]). The gauge should be adjusted so as to mark the wood into thirds, and the stock of the gauge (the portion of the gauge containing the thumb screw in [Fig. 82]) must be used from the face side of the timber when gauging up the whole of the pieces forming a frame. The face mark on the work is indicated by a glorified comma, and the edge mark is shown by X, as in the various illustrations. [Fig. 82] shows the method of holding the gauge in the right hand whilst gauging the lines on the work.

The joint, when marked out, will appear as at [Figs. 83 and 84], and the portions which are to be cut away may be shaded with a pencil as indicated; this will prevent mistakes arising whilst cutting the work, especially by one who is not thoroughly familiar with the joint.

The distance A B, in [Fig. 84], must not be less than the distance A B in [Fig. 83].

The Two Parts of the Joint Marked.

Boring Away Waste.—Examine [Fig. 84]; the shaded portion in the centre has to be cut away, and it will greatly facilitate the removal of this waste piece by boring a hole with a twist bit at the position shown. The twist bit should be about 1⁄8 in. less in diameter than the width between the gauge lines G. The easiest method of boring out this hole is shown at [Fig. 85], which gives the correct position of the worker.

Fig. 85.—Vertical Boring previous to Chiselling.

Sawing.—The wood should be put in the vice as [Fig. 86]. Taking up a saw, with the index finger on the side of the handle, commence sawing, and proceed until you come to the position indicated by the dotted hand and saw A; this will leave a saw kerf or cut running diagonally from the shoulder line to corner of the wood. Release the vice and refix the wood so that it leans in exactly the opposite direction to [Fig. 86]; then reverse your own position and repeat the sawing, so as to cut another diagonal saw cut from the shoulder line to the corner. Fix the wood upright, as shown at [Fig. 87], and saw as shown, when you will find that the saw has no tendency to run out of the guide cuts already formed by the method used at [Fig. 86]. Remember, when commencing to saw at [Fig. 86], that it is necessary to saw inside the gauge line; otherwise the joint will be too slack, owing to the amount of sawdust removed by the thickness of the saw blade. The index finger on the side of the saw, pointing in the direction of the saw cut, will greatly help the worker to saw in a straight line, as it is natural to point with this finger to any object that is to be aimed at.

Fig. 86.—How the Saw is held for the first Cut.

Cut down the other line in a similar manner, and then with a chisel of suitable width carefully chop away the waste material. The wood may be placed edge way upon the bench, or in the vice, and the chisel should be held vertically. The hole which has been bored with the twist bit will allow the chips which are cut away to offer little or no resistance to the chisel blade. The chiselling should not all be done from one side, or a chipped under-edge will be the result; it is better to chisel the work until half-way through and then turn the other edge of the wood uppermost and again begin to chisel from the top. This method will finish the cutting in the centre of the work and prevent burred and ragged or chipped edges at the shoulder.

Fig. 87.—Third, or Horizontal Cut.

Fig. 88.—Chiselling Operation.

Cutting the Shoulders.—With regard to working the piece B, [Fig. 81], place the wood against the bench stop or in the vice, and taking up a 3⁄4-in. chisel carefully cut away a small channel, as shown at [Fig. 88]; treat the other shoulder lines in a similar manner. If the marking knife or penknife blade has been used with a fair amount of pressure so as to score the fibres of the wood, this small channel, which is to form a guide for the saw, will quickly and easily be cut. Next place the wood in the vice or on the cutting board as shown at [Fig. 89], and begin by sawing lightly at the back edge as shown. When the saw has entered the wood 1⁄4 in. gradually bring the handle down from position A to position B (dotted lines) whilst the saw is in motion. Continue sawing until just on the gauge line; then treat the other shoulder lines in a similar manner.

Fig. 89.—Sawing the Shoulders.

Chiselling away Waste.—Fix your wood firmly in any suitable manner, vice or otherwise, and, holding your chisel tilted as at [Fig. 90], pare away the blacked portion 1; then pare away the blacked portion 2; after which hold the chisel flat and by gradual operations pare away the dotted lines 3, until you come down to the gauge line; then repeat the method of cutting on the opposite side of the wood. If any difficulty be experienced by chipped or ragged edges whilst chiselling, it can easily be overcome by chiselling alternately from the outside of the wood, so that the finish of the chisel cut takes place in the centre of the work. Some prefer to chisel away the waste by placing the wood on its edge and using the chisel vertically instead of horizontally. The same methods (1, 2 and 3) hold good in this case.

Fig. 90.—Chiselling away Waste.

Joints Other than at 90°.—The two pieces forming a bridle joint are not always at right angles, as at [Fig. 81]; in many instances it is necessary that the joint be at other than 90 degrees. The work, however, is treated in a similar manner, with the exception that an adjustable joiner's bevel is used instead of a try square to mark out the shoulder lines, and that a change of direction in the grain of the wood will occur when chiselling out the work. [Fig. 91] indicates the change in the grain of the wood, and the adjustable joiner's bevel is also shown.

Fig. 91.—Bridle Joint at Angle other than Right Angle.

Fig. 92.—Sawing off Waste from Bridle Joint. (See reference on [page 39].)

THE TONGUED AND
GROOVED JOINT

T he tongued and grooved joint is used in one form or another throughout the whole of the woodworking trades, covering, as it does, a great variety of work from the laying of flooring boards to the construction of dressers, bookcases and other cabinet work.

Flooring and match boarding generally have the tongues worked on the solid board, and examples of a few of the various types are shown as follows:—