Wooden and veneered furniture, as well as other, assembled from separate structural elements made of solid wood, unfortunately, cannot serve indefinitely. And this is understandable. In addition to natural aging and various "diseases" of wood, there are loose adhesive joints, traces of careless storage, unskilled repairs, restoration and others. Most often, furniture with a weakened strength of the structural connections of individual elements, in particular spike joints, comes into restoration.

1.1. Strengthening the nest-thorn, dovetail joints

It should be noted that over the past two centuries, furniture has been assembled using various tenon joints. Most often, a socket-thorn connection or similar hidden connections were used, in which wooden pins (rods) were used. Such connections hold the base of the frame of many tables, armchairs, chairs, sofas and other furniture items. This position remains unchanged in the practice of restoration of structural elements made of solid wood to this day.

The socket-tenon connection is a rectangular version of the structural assembly of furniture and has two main methods of connection. The first is when the nest is stepped and the tenon is one end of the wood element is cut and adjusted to fit into the nest cut in the other element. In another method, the tenon is flush with one side of the planar strapping of a furniture piece, such as a table drawer.

Rice. 1. Dovetail joint

The dovetail joint (Fig. 1) is a complicated version of the socket-tenon joint. The thorns should fit snugly into the swallow-tailed nests, which increase the strength of the connection; they are disconnected only in one direction.

"Dovetail", as well as "nest-thorn", are used to connect two wooden flat elements, converging at right angles, for example, in drawers of tables, cabinets and other products.

Rice. 2. Reinforcement of the dovetail joint with inserts

Rice. 3. Reinforcement of the "socket-thorn" connection with inserts

In the case of a rod (initial) connection, one structural element (part) of furniture, with a nail glued into the socket, is inserted into the socket on the second element with pre-applied carpentry glue.

The strengthening of the dovetail and nest-tenon spike joints are shown in Fig. 2 and 3, respectively.

There are many connections in wooden chairs, armchairs, sofas, more than in other types of furniture. The joints discussed above must withstand significant loads, although sooner or later in any furniture they are weakened or completely destroyed. One loose connection leads to an increase in the load on good connections, so the weakened one must be strengthened - and the sooner the better.

In cases where the disassembly of furniture is undesirable, and its spike joints are strongly weakened, the adhesive joints are strengthened by injecting liquid fresh carpentry glue with a medical syringe and kept until the glue is completely dry. The place of gluing is fixed with clamps.

If it is necessary to ensure increased strength of the joints, then the structure of the furniture frame is strengthened with additional details: cut plates from ordinary multilayer birch plywood, glued with hot carpentry glue inside the frame and fixed screws; wooden bosses, also glued in the inner corners of the side girdle of chairs, armchairs, tables; wooden pins, which are driven with an interference fit and glue into the holes drilled in the spike joints.

During restoration work, when the spike joints are disassembled, the spikes are cleaned of old glue. To remove the glue from the surface of the thorn, use a knife, cycle, coarse sandpaper. It is necessary to hold the knife almost perpendicular to the wood of the thorn, applying force on the blade so as to remove the dried glue without pressing the knife into the wood. The nest is cleaned of old glue with a chisel by scraping, while it expands slightly to create space for an expanded tenon due to an additional spacer of a thin veneer plate. This will provide increased bond strength when re-gluing. In addition, if there is a gap in the socket-thorn joint, then a wedge is sometimes added for tight joining, and in some cases, for greater fastening, a beveled key is driven into the edge of the joint.

If the spike has a crack, then it is sawn through with a tenon saw and a low-cut wedge is inserted into the cut.

If the spike breaks, it is replaced with a new one. To do this, in place of the old thorn with a chisel, make a nest with a depth of 2-3 cm, into which a new thorn is glued.

After eliminating all defects on the parts and checking the fit of the spikes and sockets, the spike joints are again glued with wood glue. To do this, glue is applied to the spikes, dowels and gaskets, as well as to the sockets. After assembly, placing the spike in the socket, tighten the spike joints with a clamping device and hold them until the glue is completely dry.

1.2. Strengthening tongue and groove joints

The tongue-and-groove connection (Fig. 4) is used when the joining parts of the structural elements are rectangular, for example, two folding boards.

Rice. 4. Tongue and tongue connection

This connection is weakened as a result of the simultaneous shrinkage of the tongue and groove of the furniture element and the thickness of the tongue. The thickness of the ridge is restored on both sides with thin veneer spacers. If the crest has cracks or is broken off, then it is cut off with a plane. In its place, a recess is made, that is, a tongue of the same width and depth as that of the board to be attached. The boards are rallied to a thorn. The insert spike is glued into the groove, and the direction of its fibers should be perpendicular to the direction of the fibers of the parts to be joined. The dowel can be made of plain birch plywood with a minimum thickness of 5 mm, if the ribs of the tongue to be joined are of sufficient thickness.

1.3. Strengthening the connections on the dowel

Round pins are widely used to connect individual elements (Fig. 5). So, for example, a dowel is used to connect two broken parts of a chair or chair leg. The nests for the dowel are drilled with a drill of the required diameter. The head is not necessarily made of the same material as the furniture. The best pins are made from beech, which is less brittle than oak. The dowel should penetrate deeply (up to 5-6 cm) into the parts to be joined.

Rice. 5. Connection on the dowel

1.4. Strengthening the joints for a "smooth joint"

The connection of the boards to a smooth joint (Fig. 6), weakened as a result of warping of the boards and shrinkage, is reinforced with transverse dowels of a trapezoidal or rectangular cross-section.

Rice. 6. Connection to "smooth fugue"

They are inserted into the grooves made on the inner (non-front) side of the part. The dimensions of the keyway for thin boards must be at least half of their thickness. Glue the boards along the edges and glue the dowels at the same time. To do this, after applying glue, the rallying boards are placed face down on a dense and even backing board, the dowels are inserted and placed under a press. At the same time, using a clamp, the boards are squeezed from the edges. At the same time, slight warpage of the overall surface is eliminated.

Strengthening the joints on a smooth joint can be done with dovetail inserts (fig. 7) - this is a traditional method.

Rice. 7. Reinforcement of the dovetail spike

"Dovetail", sometimes called "butterflies" by restorers, is an insert in the form of double thorns. After the parts of the boards are connected, grooves are cut in the tree about a third of its thickness in the shape of the insert, into which they must fit tightly. The inserts are made of the same type of wood as the exhibit, or of durable wood (oak, beech); their fibers should be perpendicular to the direction of the fibers of the edges to be joined. The “dovetail” should be wide enough in the bridge (center). Due to its shape, this insert provides a strong connection, but some restorers consider it insufficient.

1.5. Strengthening the connections on the "mustache"

Restorers quite often meet with joints of furniture elements on the "mustache" (Fig. 8), which consist in the imposition of one element on another with an oblique cut. The parts to be joined should, if possible, have the maximum contact surface, then the reliability of the gluing will be the greatest. The glued place is strengthened with dowels or plug-in spikes.

Rice. 8. Strengthening the connections on the "mustache"

1.6. Strengthening the joints with "breadcrumbs"

This method of strengthening the elements of the furniture structure and their connections is used when the furniture cannot be dismantled. Strengthening can be done with connecting pads of any shape (Fig. 9).

To seal the crack from the inside and prevent it from spreading, you can use a lining to secure the joint vertically and horizontally. The plates are made of wood of the same species as the exhibit itself. When gluing them to a crack, it is necessary that the fibers of the linings be perpendicular to the fibers of the parts to be joined. Frequently glued cracks are not straight, then it is preferable to make not one patch, but several smaller sizes next to each other. After covering with good wood glue, if possible, they are tightened with screws. The advantage of this reinforcement of the joints is that the linings can be removed as needed.

One of the types of overlays are "crackers", which strengthen the connections of the tsarg with the leg. Some restorers object to the use of "rusks", considering them irrational. They prefer to dismantle furniture, remake the drawer side with a new internal connection. This violates the principle of maximum preservation of the original. In addition, it is sometimes harmful to remove the upholstery and then dismantle the exhibit. "Crackers" compensate for the "fatigue" of the drawer side wood, caused by numerous renewed upholstery. "Crackers" are especially useful when the bars of the seat drawer are bent and have longitudinal cracks.

Crackers are made from soft, well-glued wood species (linden, poplar). Their height should be equal to the height of the sidebar. From the inside, they are given a concave line, because this shape facilitates the upholstery and the final fixing at the corners of the side bar and leg connection. "Crackers" are installed after fixing the legs. If they fit well and are glued, then there is little need to screw them on. But some restorers, nevertheless, during gluing press the "crackers" with clamps, and after gluing they screw in the screws. It is unacceptable to use nails.

Rice. 9. Strengthening the joints with "breadcrumbs"

The reliability and aesthetics of complex structures made of wood largely depends on the correct choice of the method of connecting its component parts. This is especially true for frame products, load-bearing structures, where safety parameters come to the fore.

A high-quality connection of wooden parts is a guarantee of durability, the basis for an attractive appearance of a product, an indicator of the skill and professionalism of a carpenter and joiner.

Choice of connection type

In general, there are a huge number of types of joints of wooden blanks, so you can only talk about some of them, the most common.

One of the easiest ways to build up a wooden part (timber, log, board), to increase its width is the end connection. There are several options for its implementation. A simple and functional half-thickness (half-tree) method is often used. Depending on the expected load on the part, the cut can be flat or oblique. In some cases, the joint is strengthened with curly cutouts - locks. This type of connection prevents stretching, twisting, bending. So the timber is spliced ​​together for the purpose of lengthening.

The creation of volumetric frames or timber frames requires reliable connections at various angles. In this case, it is rational to use a thorn-groove or thorn-eye connection. The nodes at the junction of the parts withstand the load of displacement, bending and compression. If the structure requires high tensile strength, the cutouts are trapezoidal.

Additional connections of frame products, which impart rigidity to the structure, are realized using T-shaped or cruciform connections. The main stress at the joints is compression, displacement and rupture. In special cases, the structure is additionally reinforced with metal corners, screws or nails.

It is convenient to use a special box groove to connect the boards to each other in box structures at right angles. As the name implies, this method is often used to create three-dimensional structures, including furniture boxes. A well-made box joint looks monolithic, has an attractive appearance and can withstand impressive loads. When creating wooden furniture, they often use a connection on dowels, dowels and dominoes (when the groove has an oblong shape, as opposed to a round dowel).

Spike connection (spike-groove)

The simplest and one of the most reliable is the tongue-and-groove connection. It is widely used in joinery. In a similar way, wooden parts of window frames are assembled into a single whole, a variety of cabinet furniture parts, plywood sheets are made. The essence of this method is that a spike is made at the end of one part to be connected, which is inserted into the groove of the other part and fixed in it.

For work, it is convenient to use a special lamellar cutter; in the absence of one, you can get by with a simple hand tool. You will need:

• hand-held shank saw with a fine tooth;
• electric or hand drill;
• several chisels of different widths;
• sandpaper;
• measuring tool, square and pencil.

First, the workpieces are marked out. The parameters of the spike and groove depend on the parameters of the wooden parts and the configuration of the product, however, it is worth considering a few general recommendations.

Important! The thickness of the spike should be about a third of the thickness of the part, the width should be 70-80% of the width, the length should be equal to the thickness of the workpiece to be joined.

The groove parameters must also meet these criteria. In any case, it is important to ensure that the dimensions of the tongue and groove match. The parts should be connected easily, without pressure, but not fall out under their own weight. There should be no backlashes, cracks and distortions.

The groove is cut first, this sequence is due to the fact that the tenon is much easier to fit under the groove than vice versa. With the help of a saw, cuts are made, excess wood is removed with a drill, the bottom of the groove and the walls are leveled with chisels.

In most cases, only wood glue is enough to fix the parts; screws or nails will help to ensure maximum strength.

Half-tree connection

Quite often, in carpentry, various options for half-wood joints (simple or straight lock) are used. This type of assembly of wooden structures is characterized by ease of manufacture and high reliability. There are the following varieties:

• cross connection;
• half a tree - dovetail;
• gusset;
• on a mustache;
• splicing in half a tree.

The first two methods are used to connect parts that intersect at right angles. Particularly popular is the dovetail, in which the shape of the neckline is a trapezoid and the sides are not at right angles. The slot of the lock expands slightly from the end, providing a more secure fit. It should be noted that a tenon joint can also be called a dovetail if the tenons are cut in the form of trapezoids.

The second and third modes form a complete corner. Splicing is used if it is necessary to increase the length of the workpiece.

How to make a cross connection

One of the simplest is the cross connection. It is distinguished by its simplicity of manufacture, even a novice carpenter can master its wisdom. The work is done in the following order:

• markup is done. The parts to be joined are superimposed on each other. Use a ruler to draw a cut line. A thickness gauge is used to mark the thickness;
• the first part is clamped in a vice. With a hand saw, carefully, along the lines, a cut is made to the mark left by the thickness gauge. The workpiece turns. The second cut is made;
• the workpiece is removed from the vise. With the help of a sharp chisel and a wooden mallet, part of the wood is removed between the cuts;
• the second part is processed;
• the planes are leveled with sandpaper or an abrasive bar.

Now you can dock wood pieces. The connection must be tight, without backlash and gaps. If the product is one-piece, the joints are coated with wood glue, the structure is additionally reinforced with screws.

Forming corners on a mustache

One of the best ways to create corners of various volumetric products is a mustache joint. It allows you to create a monolithic structure, hide the fibers of the end, thereby providing an attractive appearance. This method is suitable for a wide variety of products, but is most often used for the manufacture of frames and cabinet furniture parts.

To create a connection in each of the wooden parts, cuts are made at an angle equal to half the angle at which the blanks meet. Most often, this angle is straight, therefore, the cuts are performed at 45 degrees, however, the angle can vary widely. The work is performed according to the following algorithm.

First, the details are marked. It is important not to forget that the markings are carried out on the long side, otherwise you may not guess with the dimensions.

On the edges to be connected, draw a line at the required angle. With a combined square, the markings are transferred to each side of the workpiece. Then a cut is made, for which it is better to use an electric miter saw, but you can also work with a hand tool. When working with a hacksaw, it is important to control the cutting angle; it will be useful to use a bar as a guide.

Finished parts are applied to each other, checking the accuracy of the fit. Irregularities will have to be smoothed out with a hand plane, to bring the angle with the help of a sandpaper. Joiner's glue is applied to both surfaces, and the product is fixed with the help of clamps. Additional strength can be achieved with studs. When working with a hammer, it is important to control the force of the impact so that the workpieces do not move.

Particularly critical connections are reinforced with bars that are glued into the inner corner. A joint that will not be visible can be additionally reinforced with a metal square.

As a result of well-done work, you will get a perfect seam. If a small gap has formed, then it can be hidden by straightening the adjacent wood fibers using a smooth cylindrical surface. For this, the shaft of an ordinary screwdriver is suitable.

Thorn in the eyelet

Corner and T-shaped (example: T-shaped connection of a window frame) intersections are conveniently performed using the tongue-and-groove method. In this case, the eyelet is made at the end of the vertical part, the cuts for the thorn are made in its horizontal component.

Work begins by marking the eyelet. The thickness of the workpiece is divided by three. With a thin hacksaw, cuts are made to a depth equal to the width of another workpiece. With the help of chisels, excess wood is removed, the walls of the eyelet are leveled with sandpaper.

The second workpiece is marked out. The width of the tenon must be equal to the width of the first workpiece, the thickness must be equal to the thickness of the tenon. The cuts are made with a hand hacksaw, the depth and angle of inclination are carefully controlled. The excess is removed with a chisel.

The final finishing in thickness is carried out using sandpaper. The parts should be connected with light effort and not disintegrate under their own weight.

Thorn in the socket

A more complex connection is the tenon-to-socket method. It requires more skill, but is much more reliable and durable. The scope of use is the same as in the previous case, namely, T-joints. The difference between this method is that the spike is made at the end of the vertical part, and a socket is cut out in the body of the horizontal part.

This is one of the most common furniture connections. Distinguish between connection with a through thorn and a blind. The difference is that in the first case, a through socket is cut, in the second, a slot is made to a certain depth.

Features of Japanese joinery

Japanese craftsmen have reached unprecedented heights of carpentry. Using traditional techniques, combining different types of joints, they create precise and reliable joints without the use of nails or other fasteners. The joining of various wooden parts is carried out solely due to the frictional force.

The reliability of these connections is based on an accurate cut. Perfectly matched lock lines on both mating parts create a connection with impeccable precision. Complex configurations of locks require a lot of experience, knowledge and ability to own the tool, but if you wish, you can learn all this.

Pulling boards together

High-quality wood is expensive, it is not always possible to buy a good board with the required parameters, and it is not always necessary. To make, for example, a tabletop, it is not at all necessary to look for a board as wide as a table, having the skills of carpentry, you can create an ideal wooden canvas with the necessary parameters.

There are many options for rallying. A board with a spike and a groove, the so-called lining, is widespread. It allows you to create even large wooden surfaces. A simplified version of it is often used - a board with a quarter joint.

Rallying on a smooth puffer (butt)

The easiest way that does not require additional elements. The side edges of the boards are planed, it is better to do this in pairs, clamping both adjacent boards in a vice and at the same time processing them. This will create a precise surface on which the unevenness of one board will be compensated by the unevenness of the other. Both boards are coated with glue and fixed until it hardens completely.

Consolidation of load-bearing elements

There are several ways to lengthen (build up) a board that is part of the supporting structure. The simplest and most reliable is a half-wood connection with subsequent overlay on the junction of the reinforcing strips. Non-critical areas can be reinforced with plywood.

The same method is used to join the boards at different angles. Precisely made cuts of the articulated parts make it possible to do without reinforcing linings, it is enough to fix the boards at the junction with screws.

Cutting without residue means that the laid logs will form an even corner, their ends will not protrude beyond the structure, a separate variety of it is a warm corner. The cut with the remainder, in turn, means that an interlacing of protruding ends will form at the corners of the building. The second method is more costly in terms of the amount of material, but the building retains heat better and is more stable.

There are various ways of connecting wooden parts, the ability to determine the optimal one for a particular type of work will significantly diversify the range of products that a master can make. A correctly chosen method will provide an attractive appearance to the product and guarantee the reliability of the volumetric structure.

What is dovetail joint

Fig 8. Dovetail connection.

• a is the distance between the spikes
• b - the width of the thorn
• в - groove width
• g - interval (one third of the width of the thorn)

In the construction of wooden houses, one of the strongest and most beautiful connections is the “dovetail”. In it, all the parts hold to each other very firmly, you don't even need to use glue. Each of the structural parts tightly grips the spikes of the other, and there is no displacement. The joint area is also quite large, often larger than other stud joint designs.

Rice. 9. Varieties of the dovetail connection

• a - open connection
• b - semi-secret connection
• c - machine-made semi-secret connection

"Dovetail" - a spike connection, which is performed in a specific order. Preparatory part: you need to measure the workpieces, then mark the grooves and spikes, providing for the mandatory bevels. Then the markup must be transferred from the wider side to the end of the part and then to the opposite side.

After that, you should file the grooves and cut them out with a chisel. With the help of a pre-prepared board, they mark the places where spikes and grooves are planned on another board. The latter along the inner edges are cleaned at an angle to prevent the tree from splitting. Upon completion of your actions, you need to connect both parts without glue. If necessary, you should fix the structure, glue the parts by pressing them so that the glue dries better.

The dovetail connection provides for the engagement of parts with specially shaped teeth. The spikes are driven into special grooves that are located on the edged board (horizontally located). The boards can only be connected and disconnected when the tenons are vertical, otherwise it is impossible. The types and methods of dovetail joints differ only in the shape of the thorns (Fig. 9).

These connections are used only for those parts that are not covered with colored varnish and paints. Therefore, the spikes and grooves of the product must be evenly spaced along its entire width and must be identical (except for the extreme ones). This will ensure a good connection quality.

Rice. 10. Marking of the dovetail joint

• a - b - sequence of execution

To mark the joint correctly, you need to precisely match the bevels of the dovetail spikes. The sequence of operations (Fig. 10) during this work must be strictly observed (in particular, when drawing). First, at the attachment point, mark the thickness of the adjacent part on the workpiece board, then mark half of this length and the line to which the distance is three times greater than the thickness of this part. If it will be necessary in the future to make the surface of the workpiece for three grooves and four spikes, it is necessary to apply marks on the line, which serves as an auxiliary one. This distance should be divisible by 10. The figure of the distance that we received, in division units, must be transferred to the marking line (Fig. 10, a).

The next stage: with light strokes, mark the middle lines on the workpiece where the grooves will be located. At this stage, the middle lines of the grooves are marked with dashed lines on the workpiece (Fig. 10, b). And in conclusion, auxiliary lines are also drawn from the points of intersection of the middle lines to the auxiliary marking line through the points on the line "half the thickness of the board" (Fig. 10, c).

To mark the bevels of the spikes, you can use a sheet of metal, for example, tin, and make a blank out of it (Figure 11). For this purpose, the craftsman cuts out the appropriate shape, trims the edges, processes the surface, if necessary (for example, from rust).

Rice. 11. Device for marking the bevels of the thorns

After the marking lines are transferred, you need to shade the drop-out areas on the product, and also mark the gaps between the spikes so as not to confuse what to cut out and what not. This will come in very handy when using a chisel. And then you can start sawing.

First, those areas are sawn where the slope is the same, and then the part is turned over and its other edges are sawed. On all sides, it is periodically necessary to check whether the blade is guided correctly and whether the cut needs to be corrected. When the grooves are cut, the chisel needs to be held only vertically, and at this time the part should be attached to the workbench in a strictly horizontal position.

First, you need to make grooves with a chisel on one side of the board, approximately to its middle. Then you need to turn the board over and make grooves on the other side of it. First, according to the rules, it is better to make spikes, then start making grooves on another board. You can do it differently: first make the grooves, then use them to mark the spikes on the other side of the board, the end one. This way you will not lose the markings on dark wood material.

To connect the parts together, you need to grip them firmly, always vertically. The cuts must be made so that they are parallel to the length of the board. Light mowing to the right and to the left is allowed. Before applying the glue to the surface, sandpaper it, except for the edges, which should not be rounded.

Then you should connect the boards in such a way that the grooves and spikes cannot split. To connect wood parts, you need to use a mallet (Fig. 12). It is important to avoid direct hits against the wood product. It is worth using a separate bar in order to protect the parts from damage and cracks.

Rice. 12. Using a mallet when joining wooden parts

After completing the connection of parts with the help of spikes, you need to correct mistakes with carpentry putty. It needs to be distributed over the slots, and not over the entire area of ​​the gusset. Therefore, it is better to use a chisel rather than a large trowel. It is better to press the putty in those places where correction is needed, and not in all in a row. Instead of chisels and saws, today most carpenters use specialized machinery to cut through complex types of thorns. There are also certain types of groove cutters. If you equip it with a special guiding device, you will get perfect grooves in the wood with an even distribution.

Fig 13. Preventing splitting of grooves in the dovetail joint

• 1 - bevels
• 2 - additional bar

There are also effective ways to cut grooves using metal templates. They are used by attaching them to a drill. To prevent the grooves from splitting, small bevels are made to connect the dovetail. They are performed along the edges on the inner area of ​​the thorns. The process of gluing the dovetail joint must be done sequentially. An additional plank is also required here. It will help to correctly distribute the load - only the connecting grooves will receive it. This will help prevent damage to the cleats (fig. 13).

If you want to make furniture from solid wood, you will have to take certain measures against deformation of the wood. The list of such measures also includes the selection of the appropriate connection.

There are a lot of ways to connect wood parts so that they do not deform in the future. One of the most effective is the dovetail. The parts are connected to each other in such a way that it is practically impossible to separate them without glue. Each thorn is clamped like a plier. The strength of the connection is further enhanced by the fact that the area of ​​the joint areas covered with glue is much larger here than with a simple joint without spikes.

In addition, the “dovetail” connection can rightfully be called decorative, since it can decorate any piece of furniture, of course, provided that all the teeth are made carefully and accurately. And this will require painstaking work with a saw and a chisel. All grooves and tenons must fit exactly together, and all fugues must be equally narrow. This accuracy is unlikely to be achievable the first time: try to gain experience with simple boards first.

Many interesting and beautiful examples of the dovetail connection can be seen when looking at old furniture.

The dovetail joint is considered the most beautiful, reliable and durable corner joint. It is not so easy to execute.

This is done like this

• Cut parts of the required length from the boards.
• On one of the boards, mark the spikes and grooves.
• Transfer the markings from the front face of the board to the butt and then to the back face.
• Saw through the grooves and cut them out with a chisel.
• Using the treated board, mark the location of the spikes and grooves on the other board.
• After finishing the second board, try to connect both parts without glue and, if necessary, make corrections.
• Apply glue to the joints, carefully connect the parts and hold them under pressure until the glue seizes.

WHAT YOU NEED

Materials (edit):

Wood blanks Glue.

Instruments:

• Ruler.
• Pencil.
• Awl or knife.
• Square.
• Tenon saw.
• Chisels of suitable width.
• Workbench.
• Clamps.
• Hammer.
• Mallet.

The shape of the grooves and spikes in the dovetail joint

The beauty of this box lies in the harmony of the material and the corresponding design using the dovetail connection.

Homemade device for marking the bevels of the thorns: cut out a template from a thin sheet of metal and give it the appropriate shape.

Perform markings on parts of the required length

Before marking the spikes and grooves, measure the part again, it must have the required width. If the width of the part is greater than it should be, then the markings will be inaccurate and, therefore, unusable.

Choose the right chisel

Before you start machining the grooves, check that the chisel you have is the correct size. Take care of the right tool well in advance if you plan on making very thin pimples. Chisels come in various widths - from 4 to 40 mm.

The bar protects against damage

Never hit wood directly with a mallet when connecting parts. Use a small block of wood to protect parts from damage.

More about the dovetail joint

When doing a dovetail joint, both parts are interlocked by means of a special tooth shape. The vertically standing board shown in the figure has spikes that are driven into the grooves of the horizontally located board. It is possible to connect and disconnect the boards only with the vertical position of the spikes. Otherwise, this cannot be done.

The boards connected in this way react differently to the load. And therefore, it does not matter in which part the grooves are made, and in which spikes.

In drawers, spikes are made on the front board, grooves are made in the side walls. Since the greatest load on the box occurs when it is pulled out, the connection will be most durable precisely with this arrangement of the spikes.

In the hinged shelf, the maximum load is on the horizontal parts.

They should be with spikes that will hold the curly grooves in vertically located parts.

The tenons should always be narrower than the grooves, especially when using dense and durable wood. The peculiarity of the “dovetail” connection is also in the fact that the spikes and grooves in the finished product look different than when unfolded, as shown in the figure below.

Even distribution

Products with dovetail corner joints are not covered with colored varnish. Therefore, the arrangement of the spikes and grooves must be uniform over the entire width of the parts. The extreme spines may be slightly wider or narrower. All other cleats and grooves must be the same.

Dovetail tracing

Experienced carpenters can distribute the tines practically by hand. For those who are just starting to master this method of connecting parts, we recommend using a ruler.

For boards up to 15 cm wide, for example, four thorns and three grooves or five thorns and four grooves are marked. For boards up to 20 cm wide - five thorns and four grooves or six thorns and five grooves. An approximate distribution pattern is as follows: the ratio of the average stud thickness to the average groove width is 1: 2.

You can very accurately draw the spikes and their bevels according to the scheme shown in the figures on the right.

Other methods of division are also possible. You can choose, for example, a smaller stud width. In the so-called English joint, the spikes are very narrow and the grooves are wide. However, in any case, the pins should not be too large to damage the narrow parts of the grooves.

Mark on the part parallel to the end edge of the thickness of the board, then half the thickness and then draw a line, the distance to which from the end is equal to the thickness of the board, multiplied by three. To now accurately distribute the four spikes and three grooves, draw marks on the oblique auxiliary line, the distance between which is a multiple of 10. Then transfer this division to the marking line.

Here, the dashed lines show the middle lines of the grooves: the points of their intersection with the auxiliary line at a distance of "threefold thickness" of the board are very important for the final marking.

From the points of intersection of the middle lines of the grooves with the auxiliary line, draw lines through the points on the marking line "half the thickness of the board". In this way, the tenons and grooves will be precisely marked.

Markup

So you've marked out the spikes and grooves on the face of the board. Now you need to transfer the markings to the front side.

To do this, you need a square and a well-sharpened pencil, awl or knife. Depending on the type of wood, it may be useful or even necessary to cover the end side of the board with chalk: on a white background, the markings will be more visible. From the front side, the markings are transferred to the back face of the board.

The markings will be more accurate if the part is fixed to the workbench.

Markings with symmetrical elements on one part should be applied at the same time, so that, for example, the contours of the spikes in the corners of the drawer coincide.

With the help of a sharply sharpened pencil (or awl) and a square, the marking lines are transferred from the front face to the end side of the board.

Cutting grooves

After transferring the marking lines, before starting to saw, shade the drop-down areas on the details - the gaps between the spikes. So you will not confuse anything with further cutting and working with a chisel.

The part should be fixed on the workbench in such a way that the marking lines of bevels parallel to each other take a strictly vertical position. This is easy to do if you use a square. First saw through the grooves on one side, then turn the part over, fix and saw through the remaining bevels of the grooves.

Place the saw not on the marking line, but close to it on the falling out section of wood. Check from time to time on both sides of the board to see if the saw is pointing correctly or if the kerf needs to be corrected.

The grooves are cut with a chisel, which should be kept strictly vertical. In this case, the position of the part itself should be horizontal. It is possible to more accurately guide the chisel when another board is fixed on top of the part, the edge of which runs along the line marking the depth of the grooves.

First, the grooves are processed with a chisel on one side of the part. After the notch is made about half the thickness of the board, it is turned over and the processing of the grooves is completed. This method avoids cracking of the board, as well as inaccuracies in the processing of grooves.

Fix the part so that the marking lines take a strictly vertical position. Check with a square.

To cut grooves with a chisel, fix the parts horizontally on a workbench. The part must not slide.

Sew only sides with the same slope. Turn over and secure the part, saw through the other sides.

Thorns

Experienced carpenters prefer to make tenons first and then cut grooves on another board. But you can do otherwise: use the ready-made grooves in order to outline the spikes on another board.

At the same time, it is also recommended to cover the end side with chalk so that the marking lines are not lost on a dark tree with eye-catching growth rings. The latter must be carried out very accurately. To do this, you can use an awl or a well-sharpened pencil.

Wrap Markup Lines

The marking lines from the end side of the board to the front and back surfaces are transferred strictly at right angles to the end. The length of the spikes depends on the thickness of the grooved board. These lines must also be perfectly accurate. It is better to mark the depth of the spikes not using a board with grooves, but by measuring the length of the spikes from the end edge, transfer these dimensions to the corresponding part. Otherwise, the spikes may be longer than necessary.

When marking out, keep in mind that the front side should be the best side of the board, and the marking lines should be as accurate as possible.

It is advisable to cover the highlander of dark wood parts with chalk so that the marking lines are better visible, and the cuts are more accurate.

Compound

To cut thorns into the parts, it is again firmly clamped, but this time the position of the board should be strictly vertical, like the cuts, which are only slightly beveled in a different plane, now to the left and then to the right.

Fixing a part

To make cuts, the saw is also installed close to the marking line on the falling out section of wood. After completing the work with the saw, the part is fixed on the workbench in a horizontal position and proceeds to the processing of the intermediate sections between the spikes with a chisel. As in the case of grooving, the notch is made only in half the thickness of the board, after which the part is turned over and the "excess" wood is removed from the opposite side. In this case, you can slightly correct the cuts if there is more than necessary between the wood marking lines.

First make cuts only on the left or right side of the cleats, then parallel cuts on the other side.

After removing the intermediate sections between the cleats, carefully trim the cuts with a chisel.

Gluing

Before evenly and thinly applying glue to all pins and grooves, lightly sand the surfaces to be bonded with sandpaper, without rounding the edges. Then try joining the pieces without glue. You will immediately see if they fit together and what else can be fixed.

Carefully join the boards so that the spikes and grooves do not split. Be aware that grooves are especially prone to cracking.

The glue is applied evenly in a thin layer over the entire surface of the thorn. To do this, use the spout of a bottle of glue or a thin brush.

Joiner's putty will help correct mistakes

With an ideal connection of the spikes and grooves, all butt joints are very tight, without the slightest gaps, which not only reduce the strength of the connection, but also spoil the appearance of the product. However, even experienced carpenters do not always achieve perfect results, so you should not be discouraged if the connection in some places needs to be corrected.

Proceed as follows. Spread a plastic film under the workbench and shake off the sawdust on it. Use sawdust and glue to make a joiner's putty to help you make small adjustments.

Although ready-made joiner's putties and mastics of various colors are available for sale, homemade putty has advantages: it contains sawdust of the wood with which you are currently working, that is, this putty will fully match the tone of your product.

It is necessary to apply the putty carefully, in small portions, filling only the gaps. It is better to compact and level the filled areas with a chisel blade rather than a spatula.

Homemade putty will help you fix errors such as chipped chips or inaccuracies in work.

Sample

Wedge shaped pins can be cut quickly and accurately with a cutter using a special drill bit and template. In this case, in the course of one working operation, two parts are processed at once, installed with a slight offset to each other. True, their connection is noticeably different from the dovetail connection made in the traditional way, since when machining parts, all the pins and grooves are the same. For this reason, the connection cannot be considered decorative, but it is also beautiful in its own way, and most importantly, very reliable. The distribution of pins and grooves in such a connection depends on the size of the cutter used.

You can quickly cut thorns with a cutter if you use a special drill bit.

This is how a template is used for cutting thorns with a cutter fixed in a drill.

Tell your friends about it:

LASTOCHKIN TAIL SPIKE JOINTS

Dovetail joints are not only visually attractive, but also very durable. The ability to properly cut such thorns is a sign of the skill that comes with experience.

When assembling furniture, fasteners are now widely used - screws, dowels, various ties. However, the spike joints, including those on the dovetail spikes, do not finally give up their positions. They are quite reliable and beautiful at the same time. On such connections, you can fasten, for example, the side walls of cabinet furniture with lids. It is not easy to break the dovetail joint by stretching. Therefore, it is often used in the manufacture of drawers. But it should not be forgotten that the dovetail joint is resistant to such a load in only one direction.

Chipboard parts are not suitable for dovetail joints: this material is too loose. To some extent, plywood, boards or furniture boards are suitable here.

Dovetail spine shape

If you look at the connection from above, you can clearly see that the "dovetails" are fan-shaped spikes at the end of one of the parts. The sides of the cleats are chamfered inward with a slope ranging from 1: 5 - for "rough" but strong joints used when joining softwood parts and furniture boards, up to 1: 8 - for hardwood parts. The connection on the latter looks more attractive. And you need to know that with a lower slope, the connection may disperse under load, and with a higher slope, the spikes can collapse.

In the finished joint, "teeth" are clearly visible, engaging with the spikes. The slope of the cleats must exactly match the slope of the "teeth".

There should always be "teeth" in the joint along the edges (not halves of thorns) -

this prevents bulging of the parts to be joined.

Another factor that influences the appearance of joints is the distance between the dovetails. In principle, the following rule applies: the wider the “dovetails” (thorns) or the greater the distance between them, the better. However, there is a limit to everything, besides, products come in different sizes (for example, a chest and a box), and one should not forget about the strength of the connection.

Spike markings

The preparation of the parts begins with facing (while their thickness does not have to be the same), and then they mark
the position of the thorns and "teeth". It is better for a beginner master to give a small (1-2 mm) allowance along the length.

A bevel is used for marking. To adjust it to the slope angle of the spikes, for example 1: 6, draw two mutually perpendicular lines on paper and divide them into six equal parts from the point of intersection. Connect the sixth mark on one line with the first mark on the other. The slope of the resulting diagonal will be equal to 1: 6. According to this sketch, a malka is exhibited.

At both edges of the part with spikes, outline the width of the extreme "teeth" and draw through these points lines parallel to the edges. Further on the part diagonally
impose a tape measure or a ruler and turn it until the size between the lines is evenly divisible by the desired number of spikes. These points are marked on the diagonal, and then, using a planer, they are transferred to the end of the part. As a result of these simple constructions, the positions of the centers of the spaces between the pins were determined.

In both directions from the found centers, they are laid along the same segment (in our example, 3 mm). The distance between the ends of the segments will be equal to the minimum clearance between the pins. From these points, with the help of a bevel, finally the thorns themselves are marked. The height of the thorns is marked with a thickness gauge, exposed to the thickness

the width of the part with "teeth". Marking is done on both sides of the part.

If the part has a length allowance, it should be taken into account when marking. In this case, the length of the studs will be slightly longer than the required one. Later, when the parts are connected, the excess is removed with an end plane.

When marking, all spiked parts are marked with some conventional signs to avoid confusion.

Thorns cutting

Special tenon saws are used to cut thorns and "teeth". When using a conventional fine-toothed saw for ripping, it will need additional preparation, in particular, to reduce the set of teeth (especially if the saw is new). To do this, the saw blade is placed with its entire surface on a whetstone and one or two times is easily carried over it. The same is repeated, turning the canvas over the other side.

When cutting the dovetail thorns, the part is clamped in a vice. If there are two such parts (for example, the side walls of the drawer), the spikes can be cut on both at once.

Start cutting along the marking lines by tilting the saw back and guiding it with your thumbnail at the same time. When the cutting line is "caught", the saw is leveled and work continues until the part has been cut to the full height of the tenon (up to the horizontal mark). In no case should you go over this label.

You can now remove material between the cuts that form the cleats. This operation is performed with a chisel. Having selected the wood on one side to half the thickness of the part, it is turned over and processed in the same way on the other side.

Then proceed to cutting the "teeth". The part with "teeth" is clamped in a vice, the part with sawn thorns is placed on the butt and fixed. Then the saw is inserted into the cuts and the end part of the part with "teeth" is cut. Finally, the "teeth" are cut in the same way as the "dovetails". And in this case, you should not cut along the marked line, but so that the saw teeth lightly touch it from the outside. Finally, the material between the "teeth" is removed with a chisel.

Before joining the parts, it is necessary to eliminate possible irregularities and carefully bevel the inner edge on both sides of each stud (especially on the outer ones). This will facilitate the operation of joining parts, and such a bevel will not be noticeable in the finished product.

No related posts.

THREADED CONNECTIONS

Post navigation

Tell your friends about it: