Connection of elements along the length. Connection of wooden parts. Work options

The tree is widely used in various areas of human household activities. Especially widely wooden structures are used in construction. However, any wooden structures consist of separate parts that must be connected together in one way or another.

There are several types of connections. But you need to learn one rule: before starting work, you need to carefully mark out future cuts and always follow the markup. In the final product, the parts must fit exactly and tightly.

Methods for connecting boards and bars of small length: 1 - "butt" (butt); 2 - "in the groove and crest"; 3 - "on the mustache"; 4, 6 - "toothed" adhesive; 5 - "half a tree"; 7 - "on the rail"; 8 - "direct lock" overhead; 9 - "oblique lock" overhead; 10 - "straight" and "oblique" tension locks.

The simplest and relatively fragile is the "butt" connection. For this connection, the ends of the fastened parts are made clearly rectangular, and the ends are processed with a planer.

The mustache connection is similar to the butt joint, but here the ends of the parts are beveled at an angle of 45o. For accurate marking, a device called a yarunok is used. Such a connection is strengthened with a plywood lining or a metal square. Strengthen the connection "with a mustache" by fastening on the inside of a square or triangular beam.

More durable connections include “overlay” connections by making saw cuts. If the parts to be joined are of the same thickness, then cuts are made on both parts for half of their thickness. In the case when one part is thicker than the other, then the cut is made only in a thicker part. To enhance the strength, the parts are glued and additionally fastened with wooden dowels or screws.

If it is necessary to obtain a T-shaped connection, a half-tree overlay is used. In this case, both parts are cut if they are of the same thickness, or a thicker part is cut off with different thicknesses of the fastened elements.

The most durable connections that have come down to the present time from ancient times are connections with through spikes, on two plug-in round spikes and in the middle knitting method with a single spike. Details connected by a straight through spike are additionally fastened with dowels and glued. To make a connection on two round plug-in spikes, use a template pad made of plywood or thick cardboard to accurately drill the holes for the spikes. The median knitting with a single spike is deaf, if you need to hide the end of the spike on the front side, and through, which is much stronger than deaf.

For box joints, spiked joints with straight and oblique ("dovetail") spikes are used. Despite the higher labor intensity, the connection with oblique spikes is more durable and reliable.

For reliability, all joints can be strengthened with dowels, gluing, nails, screws, bolts, and a combination of these joint strengthening techniques.

Nagel is made in the form of a wooden rod with slightly pointed ends from hardwood. If the product will subsequently be painted or varnished, then the outer end of the dowel is recessed and puttied or a blind hole is drilled for the dowel.

Before gluing, the parts are thoroughly dried, the surface is cleaned of dirt, grease and oil stains, dust and roughened with a rasp for better adhesion. Moreover, hardwood parts are glued with a more liquid composition, and soft wood is thicker because it absorbs moisture much better. The surfaces to be glued must be carefully smeared with glue, which significantly increases the strength of the connection. The adhesive layer should not be too thick or too thin. This will significantly degrade the quality of the connection. The adhesive is applied in a uniform, dense, non-breaking layer. For reliable bonding, the product must be kept for at least a day before being subjected to further processing.

For gluing, carpentry or casein glue is used. Joiner's glue is not waterproof and at high humidity, finished products can stick out. Therefore, it is recommended to use casein glue, devoid of this drawback. In addition, casein glue is somewhat cheaper, and the bonding strength is slightly superior to carpentry.

To achieve special strength, the joints of wooden structures are strengthened with nails, screws and bolts. The length of the nail or screw is selected 3–5 mm shorter than the total thickness of the parts to be joined, and when connecting parts of different thicknesses, the length of the fasteners should be 2–4 times the thickness of the thinnest part.

It should be borne in mind that screws and nails screwed or hammered across the fibers hold the parts better.

The part of the bolt that extends beyond the parts to be joined should be slightly larger than the thickness of the nut. Washers are placed under the bolt heads to protect the wood from crushing. The slots of the screw heads are parallel to the wood fibers. It is desirable to place the slots of all screws on one straight line or parallel to each other. Before screwing in thin screws or driving in thin nails, it is recommended to make signal holes with a smaller diameter.

Screw connections are considered the strongest. You need to be careful not to split the tree. For this purpose, screws and nails should not be driven in and driven close to the edge and to each other.

The rafter system is the most complex and one of the most critical elements of the house; the comfort and operating time of the building largely depend on the correctness of its construction. The calculation and design of the truss system should only be done by experienced builders or engineers with special training.

Designing a wooden truss system is much more difficult than any metal structures. Why? In nature, there are no two boards with exactly the same strength indicators, this parameter is influenced by a lot of factors.

The metal has the same properties, which depend only on the steel grade. The calculations will be accurate, the error is minimal. With a tree, everything is much more complicated. In order to minimize the risks of destruction of the system, it is necessary to give a large margin of safety. Most decisions are made directly by the builders on site after assessing the condition of the lumber and taking into account the design features. Practical experience is very important.

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Building boards

Why you need to splice rafters

There are several reasons why splicing rafters is required.

1. Roof length exceeds standard lumber length. The standard length of the boards does not exceed six meters. If the slope is large, then the boards will have to be lengthened.
2. During construction, there are many good boards 3–4 m long. To lower the estimated cost of the building and reduce the amount of non-productive waste, these pieces can be used for the manufacture of rafters, having previously spliced ​​them.

Important. It must be remembered that the strength of spliced ​​rafters is always lower than that of whole ones. It is necessary to try to ensure that the splicing point is located as close as possible to the vertical stops.

Splicing methods

There are several ways to splice, there is definitely no better or worse. Masters make decisions based on their skills and the specific location of the joint.

Table. Methods for splicing rafters.

In this article, we will look at two of the simplest and most reliable splicing methods: butt and overlap. It makes no sense to touch the oblique cut, it is almost never used due to the large number of shortcomings.

Requirements of building codes and rules for splicing rafters

Inept splicing of rafters along the length can not only dramatically reduce their resistance to bending loads, but also cause complete destruction of the structure. The consequences of this situation are very sad. Building rules provide for certain patterns during the selection of fastener sizes, installation locations and the length of the overlays. The data are taken taking into account many years of practical experience.

Spliced ​​rafters will be much stronger if metal studs rather than nails are used to connect them. The instruction will help to make an independent calculation of the connection. The advantage of the method is its versatility, it can be used to solve problems not only with lengthening the rafters, but also with building up other roof elements. Specialized companies performed rough calculations and collected data in a table, but it only indicates the minimum acceptable parameters.

1. Stud diameter and length. In all cases, the diameter of the studs must be ≥ 8 mm. Thinner ones do not have sufficient strength, it is not recommended to use them. Why? In metal joints, the diameter of the studs is calculated for tensile forces. During contraction, the metal surfaces are pressed together so strongly that they are held by friction. In wooden structures, the stud works in bending. Separate boards cannot be pulled together with great effort, the washers fall into the board. In addition, during changes in relative humidity, the boards change thickness, thereby reducing the tightening force. Studs working in bending must be large. The specific diameter of the stud must be determined by the formula dw = 0.25×S, where S is the thickness of the board. For example, for a board with a thickness of 40 mm, the diameter of the stud should be 10 mm. Although this is all rather relative, you need to keep in mind the specific loads, and they depend on many factors.

   

2. Board overlap length. This parameter should always be four times the width of the boards. If the width of the rafters is 30 cm, then the length of the overlap cannot be less than 1.2 m. We have already mentioned that the specific decision is made by the master, taking into account the condition of the lumber, the angle of the rafters, the distance between them, the weight of the roofing materials and the climatic zone of the building. All these parameters have a great influence on the stability of the truss system.

   

3. Distance between stud holes. Fasteners are recommended to be fixed at a distance of at least seven diameters of the studs, from the edge of the board the distance should be at least three diameters. These are the minimum figures, in practice it is recommended to increase them. But it all depends on the width of the board. It is impossible to reduce the distance between the rows of studs too much by increasing the distance from the edge.

   

   

4. Number of tie rods. There are quite complex formulas, but in practice they are not used. Masters install two rows of studs, taking into account the distance between them, the holes are staggered.

Practical advice. To increase the bending strength of the spliced ​​rafter, the holes of the studs should not be located on the same line, they must be displaced by at least one diameter.

Splicing butt boards

Work is much more convenient to do on the ground, prepare a flat area. Put the bars on the ground - the rafters will have to be cut, you need a clearance for the circular saw. Before splicing, find out exactly the length of the rafters. You need to measure it on the building, use any thin long boards, rope or construction tape. If there is an error of a few centimeters - not a problem. During the connection of the rafter legs on the roof, this error is eliminated without problems.

Step 1. Lay one board on the bars, cut the end exactly at a right angle. It is better to cut off with a manual electric circular saw.

Important. Follow the safety rules, this is a high-speed and very traumatic tool. Never dismantle the factory protection of the saw blade, do not turn off the electrical overload relays.

The rafter boards are quite heavy, while cutting, give them such a position that they do not pinch the saw blade or break prematurely during recutting. Prepare the second board in the same way. Make sure that the cut is only at a right angle. The ends of the spliced ​​boards should fit snugly against each other over the entire surface, this is necessary to increase the strength of the spliced ​​rafters. The fact is that even with the weakening of the connection of the studs, the ends during bending will rest against each other along the entire length of the cut and hold the load. Studs and overhead boards will only keep the structure from spreading along the length.

Step 2 Place two prepared rafter boards side by side. Prepare the board for the overlay. We have already mentioned that its length should be about four times the width of the board. If the roof slopes have a slight slope, the distance between the rafters is large, and the roof is insulated with mineral wool, then the bending loads increase significantly. Accordingly, the length of the splicing board must be increased.

Step 3 Lay the overlay on two side by side splicing boards. Quite often, the thickness and width of the boards, even from the same batch, differ by several millimeters. If you have such a case, then level the boards on the side to which the crate will be nailed.

Practical advice. The science of the strength of materials says that the thinner the material, the greater its resistance to bending along a thin plane. This means that, for example, five boards placed side by side on an edge with a thickness of 1 cm each withstand a significantly greater load than one board 5 cm thick. Conclusion - it is not necessary to cut thick expensive materials for splicing, you can use several thin pieces of the desired length. There are enough such pieces at any construction site.

Step 4 In a checkerboard pattern and at standardized distances, drill holes for the studs. In order to prevent the individual elements from moving during drilling, they must be temporarily fixed together. Use long and thin self-tapping screws for this purpose; it is not recommended to hammer with nails. They cut or tear the fibers of the wood, the strength of the board is slightly reduced. Self-tapping screws do not cut the fibers, but push them apart, after unscrewing the boards, they almost completely restore their original strength characteristics.

Step 5 Drill holes, do not place them in one line, otherwise the boards may crack during operation.

You can find recommendations after drilling holes to separate the boards and lay jute between them to prevent the appearance of cold bridges. This is not only vain work, but also harmful. Why? Firstly, no cold bridges appear at the splicing points; on the contrary, they have the largest thickness and, accordingly, the lowest thermal conductivity. But even if they appear, there will be no negative consequences, this is a roof truss system, and not a room window or door. Secondly, jute reduces the friction force between the splicing elements, and this has a very negative effect on their strength. Thirdly, if condensate gets on the material, which is very likely, then moisture will be removed from it for a very long time. There is no need to tell what consequences the prolonged contact of wooden structures with moisture leads to.

Step 6 Insert the studs into the prepared holes, put washers on both sides and tighten them firmly with nuts. It is recommended to tighten until the washers are pressed into the tree. The excess length of the studs can be cut off with a circular grinder with a metal disc.

All other rafters are spliced ​​in the same way.

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Electric drills

Overlap splicing

This connection is easier to make, but under one condition - the total length of the two boards allows, it must be greater than the length of the rafter leg by the amount of overlap.

If you have low quality lumber, then before starting work it is recommended to lay them out on a flat surface and make an revision. For long sections of spliced ​​rafters, choose straight ones, and for segments, use curves. Although it is strongly recommended to buy only high-quality materials for the truss system, this is not the architectural element of the building that you can save on.

Step 1. Select boards and place them on top of the raised beams. If there is a desire, then you can align the ends with a circular saw, there is no desire - do not align. The condition of the ends does not affect the strength of the overlap splicing.

Step 2 Lay the boards on top of each other, adjust the length of the joint and the overall size of the rafter.

Practical advice. Boards should lie on top of each other strictly parallel. Due to the fact that the upper one rises above the lower one by the thickness of the material, it is necessary to place stands from segments under it and the bars. The thickness of the segments should be equal to the thickness of the bottom board.

Step 3 Align the boards on one of the edges and temporarily fasten them with self-tapping screws. Drill holes, install studs, washers and tighten nuts.

Butt splicing with plywood

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Clamps

One of the ways to splice rafters helps to save boards and rationally use the waste of various lumber. In this case, cut plywood sheets with a thickness of one centimeter are used.

Step 1. Lay the rafter boards evenly on the site, close the ends, pay attention to the parallelism of the side faces. The boards must be extremely uniform in thickness, the ends are cut exactly at a right angle.

Step 2 With a brush, generously smear the surface with PVA glue.

Step 3 Lay the prepared piece of plywood on the splicing site, press it firmly with clamps. During fixing, make sure that the plywood does not move from its original place.

Step 4 Fasten the plywood to the boards with long, strong self-tapping screws in a checkerboard pattern. The length of the self-tapping screws should be 1–2 shorter than the total thickness of the boards and plywood, their ends cannot come out from the back. Be sure to place large washers under the screws. Before tightening the screws, drill holes in the rafter. Their diameter should be 2–3 mm less than the diameter of the threaded part of the hardware.

Step 5 Turn the board upside down, put it under the ends of the stand, they should not hang in the air. Carefully remove all installed clamps one by one.

Step 6 Spread the surfaces with glue and place a second piece of plywood on them. Clamp it again with clamps.

Step 7 Tighten the screws with great force.

Important. When tightening the screws, pay attention that they are not located against each other. The offset must be at least three centimeters.

Step 8 Remove clamps. To strengthen the splice knot, tighten it with through pins. They should be placed in the same way as with ordinary butt splicing.

Practical advice. Holes for studs should be 0.5–1.0 mm smaller than the diameter of the stud. There are times when it is impossible to accurately select the diameter of a drill for wood. Then it is recommended to use a slightly smaller diameter drill, let the stud come in with a sufficiently large force.

During its clogging from strong blows of the hammer, the first few turns of the thread are crushed, which makes it very difficult to wind the nut. To avoid problems, start the nuts before driving the stud, now let the thread on the end be jammed, it is no longer needed. Before installing the rafter in place, check that the glue has dried. In good weather, it takes about 24 hours for it to solidify completely.

The final touch - applying glue

Important. If, during the splicing of the rafters along the length of the boards, the nuts were twisted until the washer was sunk into the wood, then this cannot be done with plywood. Carefully control the pressing force, do not damage the plywood veneer.

How to properly hammer nails into the rafter when splicing

It is not always possible and necessary to splice individual elements of the rafters with the help of studs, sometimes it is easier to do this with ordinary smooth nails. But you need to be able to score them correctly, otherwise, over time, the compression force of the boards will decrease significantly. The length of the nail should be 2.5–3 cm greater than the thickness of the rafter at the junction.

How to properly drive in nails to connect loaded or critical wooden structures?

Step 1. At a slight angle, drive the nail into the boards, but not all the way. It is necessary that the tip protrudes from the back side by about one centimeter.

Step 2 On the reverse side of the rafter, bend the nail at a right angle with a hammer.

Step 3 Drive the nail in about one centimeter more. Bend the end again, the bend angle should already be much less than 90°. The more you bend it, the more secure the final fixation will be.

Step 4 Now you can drive the nail head to the very end. On the reverse side, bend the protruding part until the sharp end fully enters the board. Remember that the exit point of the nail body and the place where its point is driven in should not lie on the same line.

This technology completely eliminates the independent weakening of the pressing force.

Prices for various types of fasteners for rafters

Fasteners for rafters

It has already been mentioned that the bending strength of the rafter at the splicing point is always less than that of the whole element. If possible try to place this knot as close as possible to the ridge, mauerlat or various spacers. Such precautions minimize the risks of mechanical destruction of the rafter leg. If this is not possible for one reason or another, then it is not recommended to place the stop under the splice at a distance of more than 15% of the leg length from either end.

Never use black screws to connect. This metal has two significant drawbacks. First, it quickly oxidizes and loses its original strength. The second - the manufacturing technology of such self-tapping screws involves hardening. Hardened self-tapping screws, when the permissible load is exceeded, do not stretch, but burst. During the operation of the roof, the relative humidity of wooden structures changes, and the thickness of the boards fluctuates accordingly. And this can significantly increase the tensile force of the self-tapping screw, it will not withstand and will crack.

Do not overdo it with the number of hardware. If there are too many of them, then the holes will significantly reduce the strength of the parts to be joined, as a result you will get the opposite effect, the build-up will not increase, but weaken.

Video - Splicing rafters along the length

Making furniture with your own hands is becoming increasingly popular due to the high cost of finished products, and due to the large number of source materials that have appeared in the public domain. At home, with a minimum set of appropriate tools, it is realistic to assemble viable furniture that will serve properly and please with its appearance. One of the most popular joining methods is gluing, which makes it possible to obtain strong, monolithic parts. Gluing can be used as an independent fastener or as a duplicating one, when using external elements, such as dowels, dowels or self-tapping screws.

Do-it-yourself glued wood

Before gluing, the parts are processed, this is done not only to clean the surface, but also allows you to open the wood pores. When applied, the adhesive composition penetrates through the pores into the wood structure, into the intercellular space, and when solidified, it forms a multitude of the thinnest threads (cobwebs) that reliably “seam” the workpieces together. The strength of a correctly made seam exceeds the strength of the wood itself; when testing for fracture, the part breaks not at the place of gluing, but along the whole tree.

Gluing a tree allows you to get products with better parameters than massive ones. In the process of gluing, elements that are suitable in texture and shades are selected, damaged, cracked and knotty areas are rejected. As a result, the strength of the glued parts is greater than that of the usual one, and by gluing the thinnest veneer onto the front surfaces, the products are given the appearance of the most valuable rocks. Wood glued according to all the rules warps, cracks and cracks much less than solid wood.

How to glue wood. Technology

There are several ways to connect parts when gluing.

• Gluing wood onto a smooth joint - joining smooth details without increasing the penetration area.

• Gluing on a microthorn - an increase in the penetration area by 2.5 - 5 mm due to the creation of a jagged relief on the part (using a milling cutter).

• Bonding on a toothed spike – increase in the penetration area by 10 mm due to the creation of a toothed spike.

• Gluing on a tongue-and-groove (thorn-groove, dovetail, oblique tenon) - additional grip due to the groove connection.

Although in certain situations where special conditions of use are expected, tongue and groove joints are relevant, in most cases the parts are glued to a smooth reveal. Modern adhesives penetrate deep into the structure and create a strong seam without additional sampling of wood.

How to glue boards together. Options

The wood to be glued must have a moisture index in the range of 8 - 12%, maximum - 18%. If there is a need to glue wet parts, a special compound is used; during the hardening process, it draws moisture from the wood. When gluing blanks with different moisture content, a difference of more than 2% is not allowed in order to avoid internal stress in the glue line due to deformation of the wetter part. The temperature of the glued workpieces varies between 15 - 20⁰С, so the work is carried out in warm rooms (18 - 22⁰С). In the cold, most compositions crystallize, which leads to a deterioration in the quality of gluing and makes the process difficult.

The final preparation of wood (planing, jointing, sanding) is carried out immediately before gluing in order to increase the permeability of the adhesive and avoid warping. It is important not only to select parts according to their dimensions, structure and external data, but also to arrange them correctly.

• When gluing along the length, only one type of sawing is used - tangential or radial;
• When gluing, both in length and in width, alternation of different parts of wood is not allowed - the core is laid with the core, sapwood (young, extreme part) with sapwood;
• Annual rings of adjacent blanks from boards or bars should be directed in different directions or at an angle to each other from 15⁰.

The standard thickness of furniture boards is 2 cm, but in order to glue wooden boards at home, when choosing boards for a board, the estimated waste during processing is taken into account, so the workpiece is selected with a thickness of up to 2.5 cm. The excess will be removed during the primary processing, when defects are eliminated, and after gluing, when grinding the shield. If you dissolve a board 5 cm thick for a furniture board, you get two blanks with the same texture and shade, which increases the decorative effect of the product. For shields, boards of wood of the same species are selected, up to 120 mm wide, so that it is possible to process the edges of the shield with high quality, the length of the blanks should have a margin (2 - 5 cm).

Adhesives

Adhesives used for the manufacture of laminated wood fall into two main groups.

Synthetic - obtained on the basis of resins or polyvinyl acetate dispersions (PVA). They are characterized by increased strength of the resulting connection, moisture resistance, biostability. The disadvantages include the presence of harmful substances that can be released into the environment during operation and further operation. This is "famous" for compositions based on phenol-formaldehyde resins. Modern PVA dispersions and their derivatives are non-toxic and are commonly used in the domestic area and are considered universal for wood. The bulk of synthetic mixtures are ready for use. The epoxy adhesive needs finishing, to work with it the hardener included in the kit is mixed with epoxy resin.

Natural mixtures - animal, vegetable, mineral. They are safe, give a strong connection, but are produced in the form of semi-finished products that are prepared before use. How to glue a tree with them: when preparing, you must strictly follow the instructions and observe the dosages, otherwise the quality of the glue will not allow you to get a strong connection. To prepare the adhesive, it is usually necessary to dilute the powder concentrate with water to the desired consistency (may require a certain swelling period) or to melt the solid particles. Direct exposure to fire is not allowed, a “water bath” is used, in which the mass with the addition of water after swelling is melted to a homogeneous consistency.

How to glue a tree

When gluing wooden surfaces, the adhesive is applied to both parts in an even layer. The thickness of the layer depends on the type of glue, its consistency and the type of surfaces to be glued - the thinner the wood, the thinner the layer. The glue should moisten the part, but not excessively; when connecting the elements, an even roller should stand out. Adhesive streaks are removed from the surface as soon as they grab a little, with a scraper or spatula. Cured excess glue greatly spoils the appearance of parts and complicates their further processing.

How to glue a wooden blank.

After applying the adhesive, the parts withstand a certain period of time, this allows the composition to penetrate deeper, at the same time excess moisture evaporates, the concentration of adhesives increases. During exposure, it is not allowed to air the seam in a draft or dust it. Some varieties of natural glue (bone, skin) must be applied hot, instantly fastening the parts without aging, since the composition loses its properties as it cools.

Wood Gluing Tool

To obtain the most durable connection, when gluing, the wood is pressed in - compressed by means of special presses. At home, for these purposes, improvised tools and means are used - a vice, clamps, cam devices, metal corner frames with clamping mechanisms. The pressure during wood pressing is maintained in the range from 0.2 to 1.2 MPa. In production, large values ​​​​are possible, at home such indicators are enough for the structural details to stick together.

Glued wood with your own hands.

Subject to the gluing technology, the adhesive seam is strong and reliable, and, unlike the method of connecting parts with metal fasteners, does not spoil the appearance.

For fans of creating household items on their own, a topic is open on FORUMHOUSE. How to organize a convenient corner for working with wood can be found in the article. The video about wooden elements in a country house shows interesting products made by users of the portal.

Timber products such as beams, boards or bars are mainly produced in a specific size, but often during construction, material may be required that has a greater length, width or thickness. For this reason, in order to achieve the required size, several types of connections are used using notches made by specialized equipment or manually by marking.

Width Connections

After fastening boards with a small width, they acquire a shield with the dimensions required for production. There are several methods for docking:

1)Docking on a smooth fugue;

in this docking method, any board or rail is referred to as a plot, and the formed seam is referred to as a fugue. Jointing can be considered of high quality only when there are no gaps between the joints of the edges of adjacent boards.

2)Rail fastening;
grooves are selected along the edges of the plot and slats are inserted into them, fastening the boards to each other. The thickness of the lath and the width of the groove itself cannot exceed 1/3 of the thickness of the timber used

3) Quarter fastening;

in joined plots, completely along the entire length, quarters are selected. With this method, quarters cannot exceed 50% of the thickness of the plot itself.

4) Docking type in a groove and a crest (rectangular and triangular);
this type of docking provides for the presence of a groove on one edge of the plot, and a ridge on the opposite edge, the shape of which can be either rectangular or triangular. At the same time, the latter is used infrequently, due to the lower level of the fortress. This kind of docking is quite in demand and is often used in the manufacture of parquet. Lack of bonding - lower cost savings due to using more boards

5) Fastening type "dovetail";
this type of docking is somewhat similar to the previous version, but only the crest here has a trapezoid shape similar to the tail of swallows. Hence the name of the mounting method.

Connection of boards into shields: a - on a smooth fugue, b - in a quarter, c - on a rail, d - in a groove and a rectangular comb, e - in a groove and a triangular comb, e - in a dovetail.

Also, in the production of wood panels, dowels, a comb with a glued into the end rail and tips into the groove are often used. Laths for pasting can have a rectangular shape or triangular. When using keys, it is better to prefer a dovetail groove. All this is necessary for the manufacture of high-quality wood panels.

Shields: a - with dowels, 6 - with a tip in the groove and comb, c - with a glued rail in the end, d - with a glued triangular rail, e - with a glued triangular rail.

Length connection

The most popular methods of joining along the length are: close, such as a groove and a ridge, fastening with a “mustache”, a notched type of adhesive bonding, a quarter, and also a fastening on a rail. The most actively used docking is of the gear type, due to its extremely high level of strength.

The connection of the bars along the length: a - end-to-end, b - in the groove and ridge, c - on the mustache, d, e - on the toothed adhesive connection, e - in a quarter, g - on the rail.

Also, the boards can be joined by splicing, when the timber segments are joined together in length. This is done in several ways. For example, in half a tree or a cut of an oblique type, an overhead lock of an oblique type and a straight one, close, as well as a tension lock of both a direct type and an oblique one. When splicing using the half-tree method, the required length must be 2-2.5 of the bar thickness indicator. To increase the level of reliability, dowels are used. For example, a similar option can be observed when building cottages from timber.

When using a cut of an oblique type with trimming the ends, the size should be equal to 2.5-3 of the thickness of the bar. It is also fixed with dowels.

Fastening with an overhead lock of an oblique or direct type is used in those structures where there is a tensile force. A straight type overhead lock is placed directly on the support itself, and an oblique type lock can be placed at the support.

If you have decided to use an oblique cut with trimming of the ends, then the bond must be 2.5-3 of the thickness of the bar. In such situations, dowels can also be used.

When fastened with a tension lock of an oblique or straight type, a high level of strength is achieved. But at the same time, such a docking is difficult to manufacture, and the wedges are somewhat weakened when the tree dries out. For these reasons, this fastening method is not suitable for structures that carry high loads.

Splicing closely implies the movement of both ends of the bar to the support and subsequent fastening with staples.

Splicing: a - half-tree, b - oblique cut, c - straight overhead lock, d - oblique overhead lock, d - straight tension lock, e - oblique tension lock, g - end-to-end.

The fastening of logs or beams can be observed during the construction of the walls of frame houses, in the upper or lower part of the strapping. The key types of fasteners are: half-tree, corner frying pan, spike type and half-paw.

Half-tree docking - direct cutting or cutting off 50% of the thickness at the edges of the bars, as well as their subsequent fastening at a right angle.

The half-leg joint is formed by cutting inclined planes at the edges of the beams, as a result of which a tight connection of the beams is obtained. The slope value must be determined by a special formula.

Cutting with a corner frying pan is very similar to cutting with a half-tree method, but differs from it in that with this type of fastening one of the bars loses a little in width.

The connection of the bars at an angle: a - half-tree, b - half-paw, c - spiked, d - angular.

Height connection

The cruciform fastening of the bars is often observed during the construction of bridge structures. With this option, you can use docking half a tree, a third and a quarter, and also a notch of only one of the bars.

Cross-shaped connection of the bars: a - half a tree, b - a third of a tree, c - a quarter of a tree, d - with a notch of one bar.

The method of building boards or bars in height is called fastening materials in height, which is very actively used in the construction of poles or masts.

Extension is divided into the following types:

1. Close with a spike of a secret type.
2. Close with a through-type comb.
3. Half wood with bolt fastening.
4. Half-tree with fastening on clamps.
5. Half-wood with steel strip fastening.
6. An oblique type cut with fastening on clamps.
7. Close with overlays.
8. Fastening with bolts.

The length of the joints themselves, as a rule, is equal to 2/3 of the thickness of the joined bars or 2/3 of the diameter of the logs.

Connection of logs during extension: a - end-to-end with a hidden spike, b - end-to-end with a through ridge, c - half-tree with fastening with bolts, d - half-tree with fastening with strip steel, e - half-tree with fastening with clamps, e - oblique cut with fastening with clamps, g - end-to-end with overlays and fastening by bolts.

spike connection

When the bars are fastened by means of spikes, a direct spike is cut on one of them, and an eye or a nest is made on the other. The knitting of beams with a spike method is actively used in the production of such joinery products as doors, windows or transoms. Each fastening is carried out on the basis of glue. It is allowed to use not only one spike, but several. The greater the number of spikes planned to be made, the larger the gluing area will be, respectively.

This type of docking is divided into: corner end type, corner middle type and corner box type.

For corner fastening of the end type, unclosed through spikes (no more than three), spikes with darkness of the through and non-through type, as well as a plug-in dowel are used. Docking angular median type is quite common on the doors. With corner fasteners of the middle and end type, you can additionally use screws, nails or bolts.

Angled middle joints on the spike: a - blind type US-1, b through US-2, c - double through US-3, d - blind into the groove and crest US-4, e - blind into the groove US-5, e - blind on round dowels US-6.

That's all the key information about the existing types of connections. This does not include connections with nails, screws or bolts. Pure wood well and a little bit of glue. 🙂

Joinery bars are interconnected by a spike joint, consisting of two elements - a spike and a socket or eye. Spike - a protrusion at the end of the bar, included in the corresponding

Rice. 42. Types of spikes:

a- single, b- double, in- multiple G- round, d- dovetail e- one-sided dovetail f, h- serrated and- nest, k, l- eyelets, m- deaf thorn n- thorn in the dark, about- spike in

semidarkness

vuyuschie nest or eyelet of another bar. The spikes are single (Fig. 42, a), double (Fig. 42.6), multiple (Fig. 42, c), that is, more than two.

A solid spike is a spike that is integral with the bar. A plug-in spike is a spike made separately from the bar. A spike with a cross section in the form of a circle is called round (Fig. 42, G).

The dovetail spike (Fig. 42.5) has a profile in the form of an isosceles trapezoid with a large base on the end face of the spike, a one-sided dovetail spike - in the form of a rectangular trapezoid with a large base on the end face of the spike (Fig. 42, e).

The toothed spike has a profile in the form of a triangle or trapezoid, the smaller base of which is the end face of the spike (Fig. 42, h), bi-oblique serrated spike (Fig. 42, g) of an isosceles triangle.

Single and double spikes are used in the manufacture of windows, frame doors, furniture; spike "dovetail" - in the manufacture of boxes, boxes; jagged spikes - for glued joining of parts (splicing) along the length.

In addition, round plug-in spikes are used when connecting plots (blanks) in width. Thorns in the dark and semi-darkness (Fig. 42, but), used in the manufacture of frames, me-

Rice. 43. The shape of the processed bars:

a- chamfer, b- headquarters (shtap), in- edge rounding G- fillet, d- fold-quarter, e- kalevka, and- thorn, h- eye, and- edge with profile processing, to- bar, l - nest, m- layout, n- plastic, about- overhang; / - shoulders, 2 - lateral edge of the spike, 3 - end face of the spike, 4 - panel, 5 - edge, b- butt, 7 - face; / - spike length, b- stud width, s - stud thickness

leucorrhea, etc. In addition, sockets and eyes are used, a deaf spike, shown in fig. 42, i, k, l, m.

A dark spike is made not only at the end connection, but also in cases where it is required that the edges of the nest be invisible, since it is not always possible to obtain even edges of the nest. To hide this defect, a darkness is cut out from the spike, that is, a part of the spike is removed along the width from one or both sides.

In order to form a spike, an eyelet, processed bars, i.e. planed from four sides to the required size, -f- pre-marked.

Structural parts and elements of joinery. Joinery products have the following main structural parts and elements.

Bar- the simplest detail; it happens in different sizes, sections and shapes (Fig. 43). The narrow longitudinal side of the bar is called the edge, and the wide longitudinal side is called the face, the line of intersection of the face with the edge is called the rib. The end transverse side of the bar, formed when trimming at a right angle, is called the end.

In the manufacture of window and door blocks, bars of small sections (vertical, horizontal sash sashes) are

they are made of solid wood, and bars of large sections (boxes) are made glued.

layouts are called bars intended for fastening glass in sashes, doors or panels in door leafs of a frame structure.

Panels are a rectangular shield made of carpentry, chipboard or fiberboard. The shape of the panels are flat, with beveled edges and with profiled edges. The panel within the doors is installed in a groove, rebate and fastened with layouts or placed on bars and fastened with screws.

folded called a rectangular recess in the bar. If the recess has equal sides of the angle, then it forms a quarter.

Platik- ledge formed to hide the gap; used in cases where fitting the part flush is difficult. The use of platik simplifies the assembly of products. It is used in the manufacture of furniture.

Overhang- protrusion beyond the base. Used in the manufacture of furniture.

Galtelyu called a semicircular recess on the edge or face of the part.

Frame consists of four bars forming a square or rectangle. Separate frames have, in addition, internal mullion bars (frame doors, window sashes with slabs).

The frames are assembled on a spiked joint. Small-sized frames are assembled on a single open through spike or spike with a semi-darkness or darkness. In the manufacture of joinery, mainly rectangular frames are used, very rarely (for unique buildings) - polygonal or round. A window sash, a window leaf, a transom, a box - all these are frames.

All connections in window blocks are made on spikes. The strength of a spiked joint is determined by its dimensions and the area of ​​the bonded surfaces. To increase the strength, the spikes are made double (in the windows).

Shields are made massive (plank) or with voids. Massive shields in order to avoid warping should be assembled from narrow slats (parts) with a width of not more than 1.5 thickness, with the selection of fibers, humidity up to (10 ± 2)%.

When gluing parts in width, the same (sapwood) faces of the joined rails should face in opposite directions, and the edges of the same name should face each other.

Joining rails along the length is allowed if the joints are spaced apart and the distance between them in adjacent rails is at least 150 mm. In panels designed for load-bearing structures, the rails do not join along the length. Wall panels, vestibules, etc. are made from shields.

To avoid warping, shields are made with dowels

Rice. 44. Types of shields:

a- with dowels b- with tips in the groove (tongue) and comb, in- with a glued rail at the end, G- with glued triangular rail, d- with a glued triangular rail, e-

multilayer

(rice. 44, a), with tips (Fig. 44.6), with glued and glued rails (Fig. 44, c, g,e). The dowels in the shields are made flush with the plane or protruding. At least two dowels are placed on each shield. Shields with dowels are designed for doors of temporary buildings, etc.

a) S) in)

Rice. 45. Methods for connecting shields:

a- for a smooth fugue, b- on the rail in- in a quarter G- in a groove and a comb, d- in a groove and a triangular comb, e- in dovetail

Rice. 46. ​​Adhesive joints of bars, boards along the length:

a- end, b- on the "must", in- on a stepped "mustache", G- on a stepped "mustache" with blunting, d- jagged e- vertical gear, w - horizontal gear, h- jagged on the "mustache", and- stepped; c - bevel angle, L- the length of the "mustache" of the spike, t- connection pitch, 6 - bluntness, 5 - gap, AT- thickness, i- spike angle

In addition to boards, multilayer shields are made, glued together from three or five single-layer shields with mutually perpendicular direction of the fibers (Fig. 44, e).

Massive shields are glued onto a smooth fugue (Fig. 45, a), on a rail (Fig. 45.6), in a quarter (Fig. 45, c), in a groove and a crest (Fig. 45, d, e) willow "dovetail" (Fig. 45, e).

Connecting wood parts. Splicing of segments along the length can be end, on the "mustache", serrated, stepped (GOST 17161-79).

End glue connection(Fig. 46, a)- this is an adhesive connection with end surfaces of gluing. Under the end adhesive connection on the "mustache" (Fig. 46.6) is understood the adhesive connection with flat bonding surfaces located at an acute angle to the longitudinal axis of the workpieces. Adhesive connectionon a stepped "mustache"(Fig. 46, c) is a joint in which the bonding surfaces have a protrusion that prevents the workpieces from moving in the longitudinal direction during tension. A connection in which the beveled ends of the workpieces have a bluntness that prevents the workpieces from moving in the longitudinal direction during tension and compression is called a connection to a stepped "whisker" with a blunt (Fig. 46, G).

Serrated glue connection(Fig. 46, e)- this is a connection with profiled surfaces in the form of toothed spikes, twirlhot glue joint(Fig. 46, e)- connection with the output of the profile of the spikes on the face of the workpiece. In a horizontal gear connection (Fig. 46, g), the profile of the spikes goes to the edge of the workpiece.

Serrated adhesive connection on the "mustache"(Fig. 46, h)- connection

on the “mustache” with profiled bonding surfaces in the form of jagged spikes.

Step glued joint(Fig. 46, and)- end connection with profiled bonding surfaces in the form of a step, the height of which is equal to half the thickness of the workpiece.

The most durable is adhesive connection on a toothed spike. This type of connection is used for splicing bars of sashes, transoms, window and door frames and other building elements.

Serrated glue connection(see fig. 46, e) are manufactured in accordance with GOST 19414-90. The workpieces to be glued should not differ in moisture content by more than 6 %. Knots larger than 5 mm are not allowed in the workpiece joining area. The roughness parameter of the bonding surfaces of toothed spikes Rmax according to GOST 7016-82 should not exceed 200 microns.

The dimensions of the spiked joints are given in Table. one.

TableI. Stud sizes

Rallying consists in connecting bars, boards, plots along the width of the edge into shields or layers into blocks. Each workpiece connected to the shield is called plot.

In accordance with GOST 9330-76, the connection along the edge is recommended, depending on the purpose of the products, to be made on a rail, in a quarter, in a rectangular and trapezoidal groove and comb, and on a smooth fugue.

When making connections to the K-1 rail (Fig. 47, a), it should be done at / equal to 20 ... 30 mm 1\ 2...3 mm more; S\ take equal to 0.4 So for wood laths and 0.25 5 0 - for plywood laths. The size S\ should be equal to the nearest dimensions of the slotted disc cutter, i.e. 4, 5, 6, 8, 10, 12, 16 and 20 mm. On the edges, one- and two-sided chamfers are allowed.

For a K-2 type connection along a quarter edge (Fig. 47, b):ho= 0.5 So - 0.5 mm, b is dependent on S 0 :

S 0 , mm I2...15 15...20 20...30 30

b, mm 6 8 10 16