4. Cutting and Joining Operations

Ever/ piece of furniture is designed to serve a certain specific purpose and at the same time with­stand wear and tear and accidental damage. In properly designed pieces the normal stresses are distributed and the proportions of the members are calculated to withstand normal strain without being too bulky or heavy.

The proportions of the parts are therefore an im­portant factor in constructing a piece that will with­stand more than normal usage, yet look well. Of equal importance is the way those parts are put together. Joints are always potential weak spots, and they must be properly designed and propor­tioned if they are to add to the strength of the piece instead of detracting from it.

The cabinet maker needs to know how to form all the common, and some uncommon, joints, and also where to use them. Since the making of joints involves a number of simple woodworking opera­tions it may be as well to study them together. Then we shall know not only "how" but "why"—and perhaps better appreciate the reasons behind cer­tain "rule-of-thumb" cabinet-making practices.

There are around twenty kinds of joints used in everyday cabinet making. Of these at least seven are so commonly employed that it is practically essential for every furniture craftsman to be familiar with their construction. Some of these joints have several variations, but only the simplest of these will  be discussed  here.   Others will  doubtless  be learned automatically as experience widens, and those shown will serve very well to illustrate the principles of joint construction and the practical means of making them.

Marking

A preliminary to any cutting operation is to mark the line along which the cut is to be made. Whether you use a marking gauge, butt gauge, try square, a straightedge, or your fingers, depends upon the location, direction, and shape of the line. But sup­pose for the moment that you are merely to cut a chamfer along the edge of a board.   This is probably done more for decorative reasons than for fit­ting, so the line does not have to be exact.

More likely than not you can draw such a line with a sharp pencil by running your fingers down the edge of the board. The pencil is held firmly between thumb and forefinger, and the tips of the third or fourth fingers held lightly against the edge of the board. It is best to draw the pencil toward yau and not to move the body during this operation.

Chamfers and Bevels

The sharp corner of the board (called an arris) is removed in chamfering, but the cut does not go the full thickness of the board. Such a full-thickness angle cut would be a bevel. Therefore, in making the chamfer, it is best to mark both the edge and face of the board. The board can then be held in a vise while you plane off the arris down to the lines. If you wish, you can take off the sharp corner first with a spokeshave or drawknife or even a chisel, and finish with the plane.

In cases where the chamfer does not go the full length of the edge but tapers off, it is called a stopped chamfer. In this case you chamfer as much as possible with the plane, and finish off the ends (stops) with a spokeshave or chisel, depending on the shape of the stop.

In making a bevel, only one line need be drawn (on the face or back of the board), and most of the work can be done with a plane. The commonest bevel is 45 degrees, in which case the guide line is marked back from the edge a distance equal to the thickness of the wood.

Beading

Another non-structural operation is that known as beading. It consists, in its simplest form, of forming a round corner in place of an arris, and is often used in conjunction with a chamfer on an adjoining board to make a decorative joint.

The line of the bead is marked off with a pencil as in the case of the chamfer. If the board is short you may be able to make a saw cut along this line, an eighth of an inch or more deep. Then you round off the arris into the saw cut with a plane on the outside and a chisel on the inside of the bead, finishing off with medium sandpaper, preferably glued to a hollowed block. All of this of course takes time and effort, with plenty of opportunities for spoiling the work. It is far better to get yourself a good combination plane with cutters for the sizes of beads that you want most often. With long boards something of the sort is a practical necessity, unless you have a power saw to make the groove.

Rabbets

A common woodworking operation is the forming of a shoulder along the edges or ends of boards or other parts. This operation is known as rabbeting, and involves cutting away a rectangular strip from the ends or edges of the piece.

Rabbets are used as joints between boards, in letting backs, tops, and bottoms into cased pieces, in forming corner joints, and, among other things, in making secret or miter dovetails. The rabbet is marked off for depth and width, i.e., on two adja­cent surfaces, and saw cuts made along the line on the face of the board to the depth marked on the edge. The second cut can also be made with a saw, though on occasion it may be best to use a chisel for both cuts. Ordinarily it is preferable to use a rabbet plane for the job. In that case you set the plane to cut to the required width and do not need to mark the wood except for depth.

Dados

A dado is merely a channel or flat-bottomed groove, and may run either with or across the grain. For example, a dado is cut across boards to receive the ends of shelves, and along the grain to receive drawer bottoms.

There are several variations from the plain dado that goes the full width of a board. Sometimes, for tidy finish, in order to conceal the fact that a shelf is let into the end, the dado is not carried all the way to the front edge of the board. It is then known as a stopped or blind dado.

In another case the shelf may be so thick that it is preferable to rabbet the end to fit a narrower dado channel. The rabbet of course would be from the underside of the shelf, and the result would be a shouldered dado.

CUTTING DADO

Still another variation might be what is called a dovetail dado joint. In this type the dado is cut with one side square as usual, but with the top side undercut at about 45 degrees. The end of the shelf is then cut to fit the dado, and must be slid in from the side.  Such a joint prevents the side of the case from pulling away from the shelf end, and the shelf holds the two sides in position.

Dados are fairly simple to make, especially short ones across the grain. All that is required is a saw cut along each line marking the width of the dado, and some careful use ot a chisel to remove the center wood. The chiseling is best done with the work held in a vise, cutting first from one side then the other. The cuts are made from the edges toward the center, the chisel removing less and less as it approaches midpoint. This leaves a triangular piece in the middle after the ends of the slot have been cut down to the finished level. The center por­tion is then removed, and the bottom of the groove trimmed smooth and even. Cuts should never be made from the center outward—this results in break­ing off the bottom edges of the groove.

If you are making a stopped dado, the saw is tilted slightly so that it does not cut beyond the end mark of the slot. The free wood is cut away, and then the slot sides are cut deeper with the chisel.

The blind end of the channel is also chiseled out.

For a dovetail dado the same procedure is fol­lowed as for the square one, but the saw is tilted in making the upper saw cut, following a guide line on the edge of the board. This makes the slot wider at the bottom than at the top. The end of the board that fits into this dado is formed by making a saw cut across the upper face and cutting down to it from the end with a chisel. If carefully done it can be sawed at an angle to meet the first saw cut.

If you use a chisel, see that it is extremely sharp. A blunt tool will break off the end grain, spoil the sharp edge, and result in a sloppy fit.

These dadoing operations can be much simplified by using a router plane to remove the waste after the side saw cuts have been made. For those cuts the best tool of all is a bench saw, but if you have such a saw you will doubtless also have a set of dado cutters to use with it and sawing will be unnecessary.

Glued Joints

An operation frequently called for in cabinet work is the making of narrow boards into wide ones by means of a joint between the two boards, usually one that is not easily detected. In furniture con­struction, the kind of joint that is made between any two pieces of wood depends primarily on the amount of stress that it must withstand in use. Other factors are the location and direction, or possible concentration of stresses, and the actual strength of the material itself. It is of little use to make a tremendously strong and heavy joint in wood that itself will break or split easily. Sometimes it is just as well to have joints that give a little under un­usual, temporary loads. That may be sufficient to prevent another part breaking.

In joining two boards, the simplest joint is one that is not reinforced in any way. It consists simply of making the adjoining edges of both boards square and smooth, and gluing them together.

The first step is to plane both edges true with the longest plane you have, taking care not to lift it. Place both edges together and see if you can detect light between them at any point. If you do, check that point on each board with a short straight­edge, such as a square. Then take a long and very fine plane cut over the high spots that are holding the boards apart at that point, and try again.

When the two boards fit together reasonably well, apply glue to both edges, and clamp them together tightly. If you have a stiff length of 2 x 2 to place under the clamp jaws on either side of the assembly, so much the better—the pressure will be more evenly distributed. In any case the clamps should not be more than two feet apart on long stock, and one foot is better though not always necessary if you use long clamping blocks or strips. Clamp as tightly as possible without damaging the wood, until all excess glue is forced out of the joint. Excess glue should be wiped off at once, from both sides, with a damp rag.

If you use three or more clamps, place alternate ones on opposite sides of the assembly, and let the bars touch the wood, some on top, some on the bottom. This will help prevent the boards buckling at the joint and keep them flat. If one or the other of the boards tends to get out of line at the ends, use C-clamps or Jorgensens to hold them level and in  line.

Some cabinet workers prefer to have the board joints hit at the ends and be slightly hollow in the center—but not more than 1/32inch. The theory is that when glued tight there will be no tendency for the ends of the joint to spring apart. Naturally, any board bowed in the oppostie direction (tight at center, open at ends) should not be used in that condition. If properly made with waterproof glue, a glued joint will be stronger than the wood be­hind it.

This type of joint is used for table and cabinet tops quite successfully. Indeed, any single board wide enough to be used for such a purpose would probably warp. That is why it is common practice to saw such boards into several strips, reverse the alternate ones so that the grain tensions counteract those of the boards on either side of it, and glue the whole together again. In doing this with wood that is to be given a transparent finish it is of course necessary to match up the grain in such a way that the joints are not too obvious.

CUTTING AND JOINING OPERATIONS

BLIND   DOVETAIL

FRAME  DOVETAIL

Spline Joints

A joint for board edges that can be used either with or without glue is the spline joint, sometimes called the slip-tongue or loose-tongue joint. This joint consists of a single groove in the edge of each board into which is fitted a continuous strip of wood. If the joint is not fastened in any way, except for the tight fit of the spline, it can adjust itself to changing moisture conditions. The boards may expand and shrink in width but there will never be an open space between them. This is the princi­ple of the panel, and it is sometimes used for the backs of cabinet pieces. On the other hand the joint can be held lightly with brads driven through both sides of the spline, or the whole firmly glued together.

The first operation in making this joint is to cut the grooves in the edges of the boards. These grooves should not be wider than one-third the thickness of the board.   A router plane is almost a necessity in cutting these grooves, unless the pieces are very short so that a back saw and chisel can be used. With a bench saw, of course, the opera­tion  is simple.

The grooves, ordinarily, are not deeper than about half the thickness of the wood. Cutting the spline therefore involves little more than sawing off a strip of wood from the edge of a board of the required thickness, and smoothing it sufficiently to make a snug fit in the grooves. Very often, a few passes with a sanding block will do the trick. The finished strip should not be too wide to permit the joint being tightly closed.

SIMPLE DEPTH GAUGE FOR   DRILLING   HOLES

Tongue-and-Groove Joints

A tongue-and-groove joint consists of a continu­ous flat strip or tongue along the edge of one board, designed to fit into a groove in the edge of another board. For most purposes this is a much more satisfactory joint than the spline type, but it is even harder to make with ordinary hand tools. However, you can buy, at quite moderate cost, a tongue-and-groove match plane designed for just such work. One side of the plane makes the tongue, the other side the groove, and each will fit the other perfectly. The joint can be made with a bench saw, but great care is needed to work on the waste side of the dimension lines and so get a tight fit. A loose tongue-and-groove joint is worse than none at ail.

Dowel Joints

It was mentioned above that glued-edge joints, properly made, are stronger than the surrounding wood. One possible effect of this would be that any excessive bearing stress on the joint might snap the wood on either side of it. Any such stress could be spread over a larger area if the wood on either side of the joint were reinforced. This is exactly what happens when dowels are used in conjunction with the glue. With wood that cracks easily they are almost a necessity.

Dowels are merely short round pieces of rod, of maple, birch, or beech. Dowels three or four inches long are smeared with glue and pushed into paired holes in the edges of boards, and the two boards are clamped together as usual. But fitting dowels is not so simple as it may sound. The dowel holes in the two board edges have to be perfectly aligned and quite parallel with the board surfaces.

The first step in doweling, then, is to make a center line along the edge of one of the boards, and mark thereon the center for the dowel holes. The next important thing is to make sure that the holes you are about to drill will be exactly opposite the holes you have to drill in the edge of the other board. There are several ways of doing this, and each cabinet maker has his own favorite method.

You can mark the center on both boards at once with a try square while they are held, edge-up, in a vise. You can drill the holes in one side, and insert in them wooden pegs or metal discs that have a sharp point sticking out of their center. If you now bring the boards together, with the hole center marks exactly in line, the points will puncture the unmarked board at the drilling centers.

Other craftsmen favor marking both boards and using a doweling jig. We prefer to mark both sets of centers at once by driving short brads into the pencil-marked centers on one board edge. The heads of these brads (projecting less than an eighth of an inch) are then nipped off leaving a tiny metal point.

Now both boards are laid close together on a perfectly flat surface and exactly in line. The edges are pressed together so the points in one pierce the other board. Separating the two boards you remove the brads. This leaves two sets of matching holes marking the centers for the drill. Of course it is still necessary to see that the holes are drilled per­pendicular to the two edges, and that they are the exact depth required.

Drilling straight without a jig requires a keen eye and a steady wrist, and constant checking with a try square. If you have no doweling jig you can improvise one with clamps and blocks of wood.

The dowel itself needs to be chamfered slightly so that it will slide easily into the holes. Some workers also slightly countersink the holes, but this is rarely necessary. The dowel also should have one or more grooves cut along its length. This can be done with a saw or a triangular file, or even a chisel. Its purpose is to release air and excess glue when forcing the dowels into the holes.

When the depth of the dowel holes is decided upon, a bit gauge is clamped to the drill at that point. If you have no gauge you can quickly make one by drilling a hole through a small block of wood that will extend from the brace chuck and leave only the desired length of drill exposed. Make the dowel itself about ⅛inch shorter than the combined depths of the two holes.

The dowels can be driven into one set of holes with a mallet, but you may need to draw the two boards together with clamps to get the dowel ends into the other set of holes. In any case they should be left in clamps until the glue is set so that you will have a good edge joint as well as a good dowel joint.

Mortise-and-Tenon Joints

One of the best-known of all furniture joints is the mortise-and-tenon. It is used to connect two pieces more or less at right angles to one another. In its simplest form it consists of a tongue (tenon) cut on the end of one piece which is held in a rectangular hole through the other piece. If the hole (mortise) does not go all the way through the wood, the joint is called a blind tenon, but the principle is the same.

In making this joint the marking out is vitally important. Mark out the mortise first, the exact height of the tenon stock, and square the lines right around the mortise member. Then, with a marking gauge (or with a mortise gauge which marks two lines at once) inscribe the two vertical lines that indicate the width of the mortise. That width should be one-third the thickness of the piece that is to form the tenon.

Presuming that the tenon piece is exactly the same thickness as the mortised member, use the gauge setting to mark out the tenon, top, bottom, and end. But first run a line around the tenon piece at a distance from its end equal to the thickness of the mortise member plus V\<> inch or slightly more. This extra length provides for smoothing and level­ing off the tenon end later.

Having checked all these dimensions against one another you are ready to begin cutting. Select an augur bit slightly smaller than the width of the mortise and drill a series of holes where the mor­tise is to be. With much of the waste thus removed, you can cut out the rest with a chisel and mallet. Work from the middle to the ends, making vertical cuts every quarter-inch or so, and finish inside the end line. Dig out the waste wood and repeat till you are at least halfway through, then turn the piece over and work from the other side.

If you are careful and keep your chisel up straight, the hole will not need trimming at the sides. If you have wandered outside the guide lines you can allow for this in making the tenon. That is why the mortise is cut first.

Use your back saw to cut the tenon, starting at the end and working down to the shoulder. The piece is held in the vise for this operation, and care must be taken to keep the saw along, but outside, the lines. The tenon is finished by laying the piece in the bench hook and cutting the waste off both sides. Be very careful to follow the lines here, otherwise one shoulder will not be snug against the mortise and the joint can rock, besides looking sloppy. The tenon can be trimmed slightly with a chisel  if it fits too snugly on first trial.

In most of the mortised joints used in cabinet work the tenon is also shouldered top and bottom.

DOUBLE TENON FOR STRONGER  STILE

ANGLE TENON

This makes a joint that is stiffer vertically, provided it is properly proportioned. In most old-time work and much of the new, when a thinner rail tenons into a thicker leg, the front of the rail is made flush with the front of the leg. This is a very im­portant point to watch in dealing with antique reproductions. It has the practical advantage of keeping two tenons entering the same leg at right angles to one another the maximum distance apart. The result is a stronger leg at the mortises.

If the joint is to be used on knock-down pieces, the tenon is made longer and a hole cut through it to receive a peg. This is also done on fixed pieces when the design calls for it. On cheaper units the peg is often put through the side of the tenon and may be round or half-round and tapered.   On the better furniture the peg is flat, with a formed head, and tapered in width only. The hole to receive it is not tapered, but if the peg is lapped in firmly it will not move.

Quite often a tenon is made so that it does not go all the way through the mortised piece. Such a blind tenon is made in almost exactly the same way as the full tenon, but with the mortises cut not deeper than three-quarters of the way through. To drill out such a mortise it is generally safest to use a Forstner bit which has no screw point to break through if you drill too far.

Panel Joints

In constructing the backs of cased pieces it is often necessary to make a frame to receive flat panels. The joints used here are either the full (through) or blind tenons, or what is known as an open tenon. The joint is complicated by the fact that all rails are either rabbeted  or grooved to receive the panel. In the case of a rabbet, one side of the tenon is made in the usual way. The other side, which incorporates the rabbet is cut back sufficiently to accommodate the rabbet on the mor­tised stile. If a groove is used both sides are cut back. In neither instance is the top of the tenon shouldered—it remains level with the bottom of the rabbet or groove.

In the case of a top rail the tenon has to be shouldered on the upper side so that the mortise will not come too close to the end of the stile. Merely narrowing the tenon would leave a gap be­tween the upper rail end and the stile because of the groove in the latter. This gap is closed by keeping the tenon the full width as far as the bot­tom of the groove. The reduced width of the tenon where it enters the mortise leaves a projection that is referred to as a haunch. Besides filling gaps, haunches on tenons also provide an extra bearing surface that strengthens the rail against twisting. This idea is sometimes incorporated in top rails that fit into legs or other vertical members. In these cases the mortise is made in the usual way. Then a shal­low slot is cut through from the mortise to the top of the member. This slot is the same width as the mortise but it may be no more than ¾inch deep. This slot serves to accommodate the tenon haunch.

The rail on which the tenon is to be cut is of course wide enough to extend from the bottom of the mortise to the top of the leg. The tenon, on the other hand, has to be rabbeted on the top side to fit the mortise. This rabbet is not made level with the side shoulders but a certain distance in front of them. This distance should be equal to the depth of the slot. The projecting piece of tenon, which was not cut away, then forms the required haunch.

The open mortise joint mentioned eariier is simi­lar in construction to the through mortise, but it is made at the end of a stile, and an open-sided slot takes the tenon instead of a regular mortise.   This joint is very easy to make since the slot can be cut with a saw and the waste chiseled out. But, naturally, it is not as strong as a regular mortise joint, and the tenon needs to be pinned in position. On the better cabinet pieces the open tenon is not used where the open end of the joint is exposed and can be seen.

Leg Tenons

In rare cases where the leg is too thin to take a pair of ordinary tenons at right angles to one another it may be necessary to miter the tenons. This makes a stronger joint than cutting the tenons square and short, but it is not a joint to be attempted by the inexperienced. This kind of joint also can be stiffened by adding the haunch described before.

If a tenon joint has to be made between two pieces that are at more, or less, than 90 degrees to one another, the construction is somewhat differ­ent. One face of the tenon remains level, i.e., parallel with the piece it is formed on. The other is cut to enter the mortise at right angles to the face of the mortised piece. The tenon therefore has one sloping side, and the mortise must be cut to suit. This all calls for careful marking out before any cuts are made.

The subject of tenons cannot be left without brief reference to draw-boring. A great many tenons are pinned by driving a short piece of dowel into a hole through the joint. In order that the two parts of the joint shall be pulled together as tighly as possible in pinning, the hole in the tenon is some­times drilled 1/16 inch or so nearer the shoulder than the mortise pin holes. When the joint is assembled, a slightly tapered dowel is driven through, thereby pulling all the holes into line and tightening the joint.

Dovetail Joints

Dovetail joints are made in various forms but the principle of them all is that of interlocking tapers.

PLAIN TENON

MARKING OUT AND CUTTING A  MORTISE

MARKING   OUT   AND CUTTING THE TENON

PEGGED TENONS

Dovetails are essentially corner joints. The single dovetail is like an open mortise-and-tenon, but the tenon is wedge-shaped so that it cannot pull out. The tenon is called the pin, and the mortise is called the socket. The wood between each pair of sockets is the dovetail—or, simply, the tail.

In constructing dovetail joints the pins are always made first, and the sockets marked out from them (The reverse of the tenon joint procedure), in the early days the pins were small and the tails large, and a few of them were use to a joint. Later con­struction favored more equal tails and pins, and all of them large. The present fashion is for many dovetails, with the pins much smaller than the tails.

When the pins and the tails are the same size the joint is known as a cistern dovetail. This design makes a very strong joint, and one that is least affected by shrinkage or expansion of the wood. It is, however, not essential for ordinary cabinet pieces.

Some cabinet makers gauge the size of the dove­tail members according to the hardness or softness of the wood.   In a hard wood the root of the pin can usually be thinner than it can in a soft wood, but under ordinary conditions this is not of great importance.

MITERED TENONS

BAREFACED TENON WITH PANEL GROOVE

HAUNCHED TENON JOINT WITH   PANEL  GROOVES

SHOULDERED TENONS INTO CORNER POSTS     (IN LINE WITH OUTER FACES)

The proportions of the pins will depend upon the circumstances (kind and thickness of wood, length of joint, etc.) but a good rule-of-thumb system is to make the wider face of the pins equal to, or very slightly less than, the thickness of the wood, in most cases the angle to which the sides of the pins are cut is about 10 degrees to the center line or 80 degrees to the base.

The dovetails used for drawer fronts are known as blind dovetails because they do not extend through the front of the drawer and therefore cannot be seen from that point. In the case of these dovetails the pins are usually made a little thinner, but they should never be less than 3/16 inch at their thinnest part. The end pins on the drawers of course have only one sloped side and are, in effect,  half pins.   In their case it is necessary to strengthen them by thickening them slightly. This is allowed for in  marking out as described later.

Cutting the ordinary "through" dovetail joint is a simple matter once the pins and tails are marked out, but great precision is called for. A sloppy fit will ruin the joint. The common dovetail has the pins spaced quite far apart, the tails often being an inch or more wide. It is therefore a good joint to   practice  on.

The first step is to prepare the two pieces of wood, cutting and smoothing to finished dimensions. The ends of the pieces also are planed off square for marking, but should be left 1/32 to 1/16 inch long for smoothing after the joint is made.

Starting with the piece that will form the pins, the end is marked around with the square at a distance equal to the thickness of the other piece that will form the sockets plus the excess that you have allowed. Now you will have to decide how many pins you are going to use, remembering that they should not be less than 1/4inch thick at their roots. If you decide on 1/4inch add 1/16 to the thick­ness of the end pins, and mark that distance off along the proper edge. Then you will be able to gauge the number of full-sized pins you can get between the end ones, allowing about twice the thickness of the pins for the tails.

CUTTING THE BLIND PINS & DOVETAILS ON A DRAWER

MITRE DOVETAIL

Having measured off these points, set your bevel to 80 degrees or thereabouts and draw the lines on the end grain of the wood to indicate the ends of the pins. In marking, use a sharp knife or pencil, or fine-pointed awl. Then, laying the board flat, use a square to extend those lines to the base line first drawn. Do this on both sides of the board and you will have an outline of each pin.

The pins are cut out by putting the board verti­cally in a vise and sawing down to the base line. To get a tight fit keep the saw on the waste side of the lines.   If the end pins are not too thin you can cut out all the waste wood between them with a chisel. Lay the work flat and cut from one side; then turn it over and finish from the other side. The spaces can be cleaned up with a paring chisel.

With the pins finished you can now use them to mark out the sockets, being sure that the pins are turned with their narrower faces toward the end of the board. Scribe around them carefully, then saw down the vertical sides. Cut the half-sockets out with the tenon saw, but use a chisel to remove the waste from the whole sockets. If the marking out is done with precision, and the cuts made on the waste sides of the lines, the two parts of the joint should go together in a tight push fit.

This matter of careful cutting is the whole secret of good dovetail joints. You will find that in laying out you do not need to go to extremes to get all pins or tails exactly the same size as one another. An approximation is sufficient provided the fit is good.

In the fronts of drawers the dovetails must be of the blind variety. This joint is a little more trouble to make than the common dovetail, especially in the cutting. In these joints you can make the pins smaller, but the end half-pins need to be thickened by about an eighth of an inch. Here again you cut the pins first (they are formed in the drawer front), but instead of cutting them through the full thick­ness of the board you leave an eighth or more to hide the ends of the tails. Therefore, in cutting you hold the drawer front firmly in a vise, end up, and, after marking out the pins, saw through the arris at an angle till the saw teeth just reach the front and top marking lines. Here you need to be extremely careful not to saw too deep and mar the end wood.

Having sawn on both sides of the center pins and one side of the end half-pins, you take the board from the vise and lay it on the bench, back up. Now you can chisel out the waste as far as possible. The triangular portion left in the sockets will have to be cut with a chisel. Some of this will need to be done with the work held vertically in the vise again. With the pins finally cleaned down to the lines by paring, you can use them to mark out the tails as before.

There are a number of other dovetails types, but the two described are commonest and easily mast­ered. More intricate ones such as the miter dovetail are not used on ordinary furniture except for special purposes. When you have become thoroughly fa­miliar with the making of the plain blind dovetails you can tackle the miter form with confidence. From the drawing you can see exactly how it is made.

Miter Cutting

A miter is a cut made at an angle to the surface of the wood, or, more technically, bevelling the ends of two pieces of wood in order to join them at an angle. In 90-degree joints the miter is cut at 45 degrees on the two ends that fit together. The line of the joint is then visible only along the corner arris that the two boards form.

The cutting of such miters is much simplified by the use of a miter box. You can make a very simple one by nailing three boards together to form a trough, and making saw cuts (kerfs) through the two upstanding sides at the required angle. The 45-degree angle is easily marked with the aid of a carpenter's square. You merely hold the square flat on top of the two parallel edges of the trough so that the same inch marks on both arms of the square touch the same edges.   You can also use a combination square for this, marking each edge in turn with the 45-degree surface. The mark is contin­ued to the second board edge with a straightedge. If the wood is over an inch thick you may be able to use a miter box with one side only because the kerf will be long enough to guide the back saw properly.   It is of course much better to invest in a metal miter box, either of the fixed or adjustable type. With the latter you can set any angle you require.

HOME-MADE MITER  BOX

SECRET TENON MITRE

HALVED K11TRE

BOX CORNER

MILLED CORMER

MITRE LOCK JOINT

After cutting the miters you can glue the two faces together but you should have ready some means of clamping the parts in position. Metal miter clamps are available, but for many jobs you can make a satisfactory clamp by screwing a wood block to a heavy board base. This block must have a large, right-angled notch cut out of one edge to form a 90-degree inside corner. A triangular block is placed in this angle which it fits exactly.

To use this device the two halves of the miter are placed together in the angle of the fixed block, and the triangular one put inside the miter. Any suitable clamp is made to straddle both blocks and tightened. This forces the triangular block tightly into the angle. The friction between it and the work while tightening presses the miter joint parts together and holds them there firmly.

On some pieces of work, where a hole in one side does not matter, you can put a screw in the wood each side of the joint, clamp the pieces flat to a board, and pull the joint together with a clamp on the screws. Better still is a small block screwed to each of the pieces. There is also a clamp made for professional use that holds the parts together with a pair of stub fingers that fit into holes in the wood.

In addition to the plain joint you can use the dovetail miter previously described; you can dowel the miter, screw or nail it (preferably after gluing) or use a loose fillet or spline, or even hold it to­gether with a keyed dovetail. You can also make a mitered half-lap joint, a secret tenon, or a dove­tail tenon. The illustrations make the construction of these joints clear; the rest is a matter of accurately making and cutting as in the case of the other joints described in detail.

There are many other possible joints for corners, some of which are interlocking. The first advance over a plain rabbet joint combines a dado and a rabbet and is known as a box corner. This is not recommended, especially in thin wood, because the dado is made of necessity close to the end and across the grain so that it is extremely weak. The same thing applies to the milled corner joint which combines two dadoes and a rabbet (or a dado, tongue, and rabbet). These joints should be used only with hard, tough woods, and where no great strain will be imposed upon them.

Somewhat better is the lock joint which combines three dadoes with two tongues. This can only be assembled by sliding one piece sidewise into the other, therefore all dimensions must be absolutely accurate and the surface perfectly straight. It is not a joint to make by hand. The lock miter joint is simpler, merely having a tongue that fits into an end dado with the outer edges mitered.

Corner Blocks

Where possible, all mechanically weak joints of any variety should be reinforced with corner blocks. These can be triangular or square in section and preferably held with glue.   The beginner, however, should confine his joint-making to tenons and dove­tails, unless he has a shop fully equipped with pre­cision power tools and has considerable skill himself.

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