Corner joints of frames. Longitudinal connection of ABB WR frames Bonding corners of wooden frames

Windows made of polyvinyl chloride (PVC) or, as they are also called, plastic (metal-plastic) windows are widely used in Ukraine. And the first plastic windows appeared in the 1960s. in Germany, where industrial production of PVC was developed.

Polyvinyl chloride– a material belonging to the group of thermoplastics. Pure PVC consists of 43% ethylene (a petrochemical product) and 57% combined chlorine obtained from table salt. To produce window profiles, stabilizers, modifiers, pigments and auxiliary additives are added to powdered PVC to impart properties such as light fastness, weather resistance, color tint, surface quality, weldability, etc.

Plastic windows can be used in industrial, public and residential buildings; there are no hygienic restrictions on their use.

PVC is a highly flammable and self-extinguishing material. It is resistant to acids, alkalis, and atmospheric influences.

As the temperature decreases, the elastic modulus of PVC increases, and therefore its tensile, compressive and bending strength characteristics also increase. However, this increases its fragility (impact strength decreases), so when installing plastic windows in winter time the risk of PVC destruction is quite high.

With increasing temperature, polyvinyl chloride gradually softens, and compressive and bending strength decreases. A sharp decrease in the strength properties of PVC begins at a temperature of +4СГС, and near +80°С there is a point of its softening. In this regard, the use of PVC windows is unacceptable in rooms with elevated temperature conditions.

In their design, PVC windows are generally no different from wooden ones. Only for the manufacture of individual elements, not solid bars are used, but hollow multi-chamber plastic profiles obtained by extrusion.

Rice. 15.8. Elements and functional dimensions of PVC profiles: 1 – main profile (box); 2 – main profile (sash); 3 – additional profile (glazing bead); 4 – double-glazed window; 5 – sealing gasket; 6 – base lining; 7 – support (distance) lining; 8 – reinforcing liner (fittings); a – gap in the vestibule; b – height in the vestibule; c – clearance; d – glazing gap height; g – glass pane pinching height

Polymer extrusion is a method of manufacturing long-length profiled products from plastics and rubber, which consists of continuous extrusion of softened material through holes of a certain cross-section. It is carried out in extruders, most often screw ones.

The profiles are usually supplied in lengths of 6.5 m. They are cut to the required size in the assembly area.

The connection of individual frame profiles and sashes is made by butt welding using a heating element. The impost is fastened using mechanical connectors, and the glazing bead is simply snapped into the corresponding grooves of the frame or sash.

Rice. 15.9. Mechanical connection of the frame with the impost: 1 – frame profile; 2 – impost profile; 3 – connector; 4 – screw; 5 – holes; 6 – washer

The welded frames and sashes are sent to the next operation - installation of seals. Middle sealing gaskets are installed in most cases by the profile manufacturers themselves. Other types of seals are inserted manually using special rollers.

Bending machines are used to produce semicircular and lancet window shapes. Of all window materials PVC has the greatest bending capabilities with different radii of curvature. But this is a complex operation. When making a window with an opening arched sash, it is quite difficult to maintain the same bending radius of the frame and sash profiles, and moreover curved profiles cannot be reinforced as straight. During operation of such windows, thermal deformations of unreinforced PVC may occur, leading to problems with a tight veil.

Rice. 15.10. Windows made of curved PVC profiles

Currently, a fairly wide selection of colors for the surface of plastic profiles is offered - from solid colors: red, green, blue, light blue to various decors, including wood imitation.

Several methods of painting (finishing) PVC profiles are used:

Coloring in mass (white and brown);

Co-extrusion;

Lamination with acrylic film;

Acrylic varnishing;

Spraying.

The most reliable, durable and weather-resistant method is co-extrusion, which is the result of the joint extrusion of acrylic and PVC, which allows you to obtain an acrylic coating on the surface of profiles in various colors with a thickness of 0.5 mm.

To solve technical and architectural problems, profile manufacturers produce a large range of products from which elements of different shapes and sizes can be easily assembled.

The entire range of products can be divided into two large groups: main profiles and auxiliary (additional) profiles.

Rice. 15.11. PVC profiles and interface units (ADEPLAST): a – box profile; b – impost; c – valves; g – glazing beads; d – reinforcing steel profile; e – seals; g – lining under the double-glazed window; h – “frame-sash” assembly; and – “impost-sash” assembly; j – fixed glazing unit in the impost; l – the same, in a box; 1 – box; 2 – leaf; 3 – impost; 4 – glazing bead; 5 – lining; 6 – seal

Profiles intended directly for the manufacture of windows, i.e. frames, sashes, imposts, frames belong to the group main products of the profile system. Typically, manufacturers produce 5...7 varieties of main profiles of each type (purpose) with different indicators for thermal engineering, statics, and design.

Auxiliary (additional) profiles are produced to expand the architectural capabilities of PVC windows and for their quick and convenient installation. Auxiliary profiles can be divided into several groups according to functional characteristics:

Profiles used to increase the architectural expressiveness of windows: glazing beads; slabs for dividing glazing; connectors; rotary profiles; decorative overlays, etc.;

Profiles used for window installation; finishing; thresholds; extension cords; flashings; ebb-connectors; profiles for shutters, etc.;

Restoration profiles attached to the existing frame of an old window without dismantling it;

Reinforcing profiles used in cases where the impost or connecting profile does not pass the static calculation.

Rice. 15.12. Examples of elements decorating large window glazing surfaces: a – adhesive overlay; b – crosspiece; c – double-sided pads with spacer strips

Windows of almost any configuration, any color and with any type of opening can be assembled from products of the profile system - both with an impost for double-hung windows or a window and a balcony door, and without it, with the so-called flashing cuff, or shtulp.

Connectors– profiles designed for connecting window (white) door frames to each other in structures consisting of two or more frames. Connectors can be designed for joining profiles at different angles, and their type is selected, as a rule, taking into account the requirements of window statics. These profiles are indispensable in the manufacture large windows, strip (horizontal and vertical) glazing, as well as bay windows of various shapes.

Rice. 15.13. Types of PVC profile connections: a – standard; b – connecting profiles; c – the same, with amplification; g – connector for right angle; d, f – connecting profiles for variable angles; 1 – silicone; 2 – reinforcement bent profile; 3 – steel plate

Rice. 15.14. Details of glazing of bay windows (KVE): 1 – frame profile; 2 – connecting profile at 90°; 3 – rotating connecting profile; 4 – cylindrical profile; 5 – intermediate profile; 6 – reinforcement liner; 7 – sealing gasket; 8 – screw; 9 – expansion profile; 10 – butyl tape; 11 – insulation; 12 – facing brick; 13 – partition; 14 – drywall; 15 – facing corner

Extenders– profiles designed to increase the height of the window frame, which is often necessary, for example, when installing windows in old buildings with large quarters, when making plinths for kiosks, when installing balcony doors, etc. Extenders can be the same width as the window frame or narrower. For example, smaller extensions are used to attach external flashings or window sills.

Rice. 15.15. Balcony door made with an expansion PVC profile (VEKA)

Connector ebbs– profiles designed for effective drainage of water from the window structure and for connecting external sills and window sills. They can also be used independently to avoid water flowing under the frame.

Finishing – various types facing profiles for finishing window slopes. There may also be separate profiles: corners, trims, plugs, etc.

Thresholds– are made of aluminum, but are included in the programs of PVC profile suppliers. Thresholds are divided into thresholds for entrance doors and overhead protective profiles for balcony doors.

Rice. 15.16. Balcony door opening outwards

Design features of PVC profiles. As already mentioned, PVC profiles have hollow chambers filled with air inside. The chamber is a closed internal cavity (system of cavities) of the profile, located perpendicular to the direction heat flow. The chamber may consist of a number of subchambers separated by partitions. The chambers perform various functions, for example, for installing reinforcing inserts or as self-ventilation channels. Basic profiles are available with three, four or five cameras. The number, dimensions and location of cameras are determined by technical calculations.

The profiles have additional grooves that are used for installing glazing beads, fittings and for fastening additional elements. The thickness of the profile walls, depending on their location, is 1.5...3 mm.

Big camera called basic, it serves to install a reinforcing liner (reinforcing profile), since PVC products are exposed to high temperatures and external loads change their shape, increase in size and become deformed.

The cross-section of the reinforcing liner and the thickness of its walls are calculated according to static requirements. They may have different shapes- both U-shaped and closed rectangular. The thickness of the walls can be different - from 1 to 3 mm. Reinforcing (reinforcing) liners are made from galvanized bent steel (main option), aluminum, fiberglass.

In strong winds and rain, individual drops may penetrate to the bottom of the rebate of the glass unit or frame. To drain this water, the bottom of the rebate has an inclination towards the outer edge or a special recess. Next, water through special drainage holes in the walls of the frame and sash profiles falls into drainage chambers, from where it is discharged outside.

In Fig. Figure 15.17 shows the frame and sash combination of the VEKA system at the bottom of the window. The outer chamber of both frame and sash profiles is filled with polyurethane foam for thermal insulation, and the drainage chamber as such is located entirely in the warm zone. From the frame profile, water flows down the support profile, which can also be insulated.

Rice. 15.17. Frame and sash profiles with polyurethane foam filling (VEKA): 1 – external chambers; 2 – drainage chambers; 3 – stand profile; 4 – drainage

For fastening the fittings (hinges) connecting the frame and sash, there are special chambers for fastening accessories. The presence of such cameras is due to the fact that the mounting screws must pass through at least two PVC walls with a total wall thickness of at least 5 mm.

The frame and sash can be positioned in relation to each other in different ways. The outer surfaces of the frame and sash can be in the same plane, partially or completely displaced. When the frame and sash are positioned flush, the sash profile makes it possible to install glass units of greater thickness.

Rice. 15.18. The location of the PVC profiles of the frame and sash in relation to each other: a – flush; b – partially displaced; c – completely displaced

A groove is provided for fastening the glazing bead in the sash and frame.. It is used in a frame if the window is blind and, therefore, the glazing is installed directly into the frame. The profile of the glazing bead can be very different, which is determined by the architectural design. The glazing beads are most often fastened by sliding them into a groove, which makes it possible to replace the glazing if necessary.

There is also usually a groove on the glazing bead where a seal is inserted, tightly pressing the glass unit. In recent years, the use of systems with additional extruded sealing elements, which form an inextricable unit with the bead itself, has increased.

Sealing gaskets (profiles) are installed not only in the glazing bead area, but also in the sash for fastening glass on the other side, as well as between the frame and sash for a tighter connection to each other (to ensure air and water tightness).

Various options for sealing the plane between the frame and the sash are possible, due to technical and architectural reasons:

External seal (in the frame) and internal seal (in the sash) – seal along the rebate;

Middle seal supplemented by an inner seal (in the sash);

The triple seal is a combination of the previous two; used to improve sound insulation.

Rice. 15.19. Frame and sash sealing systems: a – double-circuit; b – three-circuit

Methods for installing PVC windows in wall openings of various modern designs are shown in sufficient detail in Fig. 15.20.

Rice. 15.20. Installation of PVC windows in wall openings: a – with external plaster; b – with external brick cladding; c – the same, ventilated type; d – from three-layer concrete panels; 1 – window frame profile; 2 – expansion profile; 3 – sealing cord; 4 – insulation; 5 – casing; 6 – vapor barrier; 7 – silicone sealant; 8 – sealing gasket; 9 – antiseptic timber; 10 – waterproofing; 11 – mounting anchor; 12 – drywall; 13 – paint vapor barrier; 14 – antiseptic board

The easiest way to make a frame is to connect the planks at right angles. In this case, the joining area will be equal to the cross section of the plank. If you cut the planks at an angle of 45 degrees, the cut will be noticeably larger and, therefore, the connection will be stronger.

However, it's not just about durability. With this combination of parts, the frame looks more elegant. And yet, as a rule, one adhesive connection is not enough. Even on medium-sized frames, not to mention large ones, the connections should be additionally secured - with nails, insert or through tenons, corners.

The most common frame shape is rectangular. But it can be hexagonal or octagonal. It is clear that with such a frame the joining seams run at a different angle. However, in any case, this seam should divide the corner of the frame itself in half.

The slightest deviation from the given angle - even by one or two degrees - will lead to the fact that the cut strips will be impossible to fit closely to each other. This means that an accurate and therefore durable connection will no longer be possible.

To make a frame for a picture according to the scheme described on pages 206-209, you need to have a solid set of materials and tools and the qualifications of a cabinetmaker. For our home craftsmen, this material is unlikely to have “applied” value. Wrong requests, wrong opportunities.

Such connections can be seen on any picture frame. The glue seam between the two planks runs exactly at an angle of 45 degrees, that is, it bisects the right corner of the frame.

It's done like this

Cut the planks according to the markings.
Treat the cut with a plane, in some cases just clean it sandpaper.
For extra strength Drill holes for tenons in the cut areas.
Cover the sections with glue and secure the joints using clamps until the glue sets.
Secure the frames from the outside with nails or reverse side wavy wire or corners.
If necessary, glue thin ridges on the outside.

What you will need

Materials:

Frame strips.
Carnations with a hidden head.
Wavy wire.
Picture or window corners.
Glue.
Screws.
Thin wooden plates or pieces of plywood for tenons.
Wooden rods for tenons.

Tools:

Saw with a “back”.
Drill or drilling machine.
Bow saw.
Hammer.
Miter box.
Plane.
Marking pins.
Sandpaper.
Frame clamping devices.

Corrugated wire and corners

How to strengthen an old frame

When repairing an old rickety frame, they often limit themselves to scraping out old glue from the seams and re-glue the frame. However, it would not hurt to additionally strengthen the frame with thin ridges, provided that it is coated with a transparent colorless varnish. After inserting the ridges and cleaning the outer corners, it is advisable to coat the frame with a new coat of varnish.

Sawing

First, markings are applied to the planks according to the format of the picture, leaving a margin for corner connections. The next step is to apply 45 degree angles. This marking will indicate the outer sides of the frame.

An ordinary miter box secured to a workbench with a clamp will help you cut the planks at an angle so that the position of the miter box itself and the plank in it is stable. However, an ordinary wooden miter box allows you to saw the workpiece only at an angle of 90 and 45 degrees. To make a frame with a complex contour, you will need a more advanced and expensive device, using which you can cut the workpiece at an angle of 67.5 degrees for a pentagonal frame or 60 degrees for a hexagonal one. The blanks for frames should be sawed with a finishing saw (with a “back”).

With this device you can cut wooden blanks from different angles.

A regular miter box should also be firmly fixed. A stable position of the miter box and the bar in it is necessary to obtain an even cut.

Cleaning the cut

No matter how thin the saw is, sawing alone will not produce a perfectly smooth cut.

Therefore, each cut is carefully processed. First of all, you need to remove the “fringe” from back side workpieces (such a flaw is inevitable, since the saw works in jerks). It is also necessary to clean the entire cut surface. Only then will the connection be tight.

Using a plane

It is customary to clean surfaces with sandpaper. But in this case, it is better to use a plane and place the workpiece in a device that will “allow” the plane to remove the “extra” without changing the angle of the cut.

Such an auxiliary device can be made from a piece of board or a piece of wood slab, as well as a small block and a piece of plank. The block is hewn on one side, and the plank is sawed off at an angle of 45 degrees, after which it is sequentially (see photo above) screwed to the board with screws.

The plane must be carefully guided along the cut (with the right side of the plane facing the workbench). Only the workpiece should be hemmed, but in no case the auxiliary device, otherwise the cut itself may be damaged.

Using a simple device, you can process a cut better with a plane than with sandpaper.

Bonding

Until the glue sets, the miter joint, as carpenters call it, must be under pressure. To do this, clamping brackets are installed using spacer pliers. You can also use a special frame vice, which is sold in various designs. Choose from them the ones that best suit your frame. When using regular staples, first check that the framed pieces form perfectly right angles. It is important here that all diagonal cuts match exactly in length. Note that when using expensive frame vices, time for control measurements is saved.

The frame is assembled. All that remains is to secure the glued joints with clamping clips, which are installed using spacer pliers.

Special frame vices fix the connections with great precision.

Fastening with nails or corners

Even for small picture frames corner connections It is recommended to additionally secure (after the glue has set) with countersunk nails.

The heads are called secret heads because they allow the entire head to enter the tree. Only a small depression remains, which must be filled with putty or carefully steamed with water. It’s done, oh, like this: a drop of water is introduced into the recess, and then heated with a soldering iron or iron. The wood fibers, clamped by the rod and the head of the nail, swell and fill the recess. As a result, the surface is leveled.

Another very common way of additionally securing the corner joints of frames is “flashing” with wavy wire (also called wavy nails). Two or three pieces of such wire are driven across each joining seam on the back side of the frame.

Secure the corners with screws

Corner joints of large heavy glazed frames can be secured with special frame or window frames metal corners. They come in different sizes, so you can choose suitable corners for any frame format.

The corners are not visible from the outside, but you can make sure that they are not noticeable even from the side. To do this, trace the contours of the corners on the back side of the frame and then use a chisel to remove a layer of wood of the required thickness along the contour. The corners are inserted into the resulting recesses and screwed tightly.

Hidden Thorns

A rectangular tenon joint looks the neatest because the tenons are completely hidden.

Insert the spikes across the joining seam and as close as possible to inside frames. The holes for the tenons are first drilled on one strip. Then, using marking pins inserted into the finished holes, the locations for drilling in another strip are determined.

There is another way of marking: small nails are driven into the bar, then they are bitten off with pliers. When two planks are tightly joined, the protruding tips will leave the necessary marks on the second workpiece.

Two or three tenons will add extra rigidity to any joint, even large, heavy frames.

Only with an exact match of the holes for the insert tenons can you obtain a perfect rectangular connection from two frame parts.

Connections with through tenons and ridges

Processing planks for securing corner joints with through tenons or inserted ridges requires a certain vocational training. After all, you need to accurately cut the grooves for inserting tenons or ridges, which is quite difficult for a beginner, but it is thanks to the grooves that the area of the joining areas and, accordingly, the adhesive coating increases noticeably. The result is a connection of increased strength.

Grooves for through tenon

After the planks for the frames are prepared, you need to cut grooves on the oblique cuts approximately one third of the width of the plank (but no more). However, you can also take the thickness of the wooden plate, which will be used as a through tenon, as a guide.

When making a tenon, you should pay attention to the fact that the fibers in it are located transversely. If the direction of the fibers and the seam coincides, then the tenon, after rigid fixation with grooves, can easily break.

The through tenon, in the form of a thin wooden plank or plate, must be long enough to fill the entire length of the grooves.

Inserting ridges from the outside

It is somewhat easier to secure a corner joint with push-in ridges than with a through seam. After the frame is assembled and glued, cuts are made at the corners from the outside with a depth of approximately two-thirds of the thickness of the plank, into which thin wooden plates (ridges) coated with glue are inserted.

It is better to glue not one, but two ridges. Moreover, they do not have to be placed in parallel. The cuts can be V-shaped in relation to the middle of the plank and to each other.

This wedge-shaped arrangement of the ridges gives the corner joints of the frame additional strength.

It is quite difficult to make precise grooves in the oblique cuts of the planks, but the result is worth the effort: the connection obtained by inserting a through tenon into the grooves is very reliable.

The thickness of the ridges should correspond to the thickness of the cut.

The tenon must be long enough to fill the entire groove. After gluing, the protruding parts of the tenon are sawed off, and the irregularities are smoothed out.

The ridges glued on the outside should fit into the cuts until they stop.

Only after the glue has set can you saw off the protruding parts of the tenons or ridges.

When choosing aluminum or PVC glazing, you have to think about how to connect a balcony frame from 2 parts so that the joints between them fit tightly, and the structure itself is strong, durable and does not loosen under gusts of wind, has no cracks, does not serve as a source of cold penetration and looks decent , aesthetically pleasing.

Design window frames provides for such a need. For this purpose, the profile has side cutouts designed specifically for the use of a connector, compensator or expander. Let's consider this possibility.

Connection of two balcony frames

Connection piece for composite frames

If the balcony is glazed with two or more frames, to ensure a reliable connection, a special profile is used that presses them tightly at the junction points. The part brings together window configurations of any height well.

Kopplung - connector is an element consisting of 3 parts (3 mm):

Double profile: PVC and metal, reinforcing it, ensure the strength of the connection.

The side projections that fit into the grooves of the frames being joined are necessary for their coupling.

Aesthetic exterior, visible from outside and inside.

In order to thermally insulate the joints, adhesive tape is additionally used.

How is assembly carried out?

For example, consider a connection in the vertical direction. You will need a connector, which is first attached to the lower frame, inserting protruding elements into its grooves. To avoid distortion, you can tap the surface, but only on metal profile, but not like plastic.

A hole is drilled in the metal part of the profile, crossing the frame, and a fastening screw is screwed in (has a temporary function and is only necessary for the vertical arrangement of frames).

The prepared lower frame is installed on the balcony railing, a second frame is built on top, inserting the protrusions of the connector into its grooves. Trim by light tapping wooden hammer, make sure that there are no distortions, and begin fastening.

Using a long drill, make through holes for screws 100 mm long and 5 mm thick, passing them through the profiles of the first frame, connector, and second frame. When screwing in the screws, they are recessed into the profile so that there are no subsequent problems with installing the double-glazed window.

Important! In accordance with safety regulations, The joining of balcony frames must be carried out by at least 2 people - no less. These must be experienced professionals who know how to connect a balcony frame of 2 parts in a vertical or horizontal position, and not cause harm to others.

It just so happened that the U-shaped niche for the electrical cabinet took shape with dimensions of 35x35 cm in cross-section and a height of approximately 3 meters. The width was quite enough to accommodate a DIN rail for 12 modules, and there was also depth for free cable routing. The question arose about what to attach the DIN rails to. I found CS’s blog (many thanks to him for such work), and learned about WR frames there. I decided to use them for the skeleton of the cabinet. It should be added that my electrical project contained diffs of the 941st series, about which I just didn’t know a damn thing, just like I didn’t know about the existence of UZM. In general, the old project was abandoned, but in the new one the composition and volume of the module has changed radically. Now the entire height of the niche has become in demand.
Among the equipment, two built-in ABB boxes for 36 modules (ABB 12046) were purchased long ago:

Overlays for the built-in parts of the boxes can be beautifully placed one above the other with only a small indentation. Butt jointing is completely unpresentable and impossible. The minimum indentation turned out to be exactly one DIN rail:

There were almost 144 modules, and I had to buy a couple more boxes 12046. It turned out to be 4 “floors”. Some of the remaining part of the module, such as current transformers, terminals, etc., had to be moved into the depths of the cabinet, onto the “rear” DIN rails.

Now, actually, about the main thing. WR frames, if I'm not mistaken, are never longer than 2200 mm. But you need to build 3000 mm. I bought 6 pieces of WR1101 (2100 mm). There is no standard connector for their longitudinal connection, because installation and maintenance at such heights are not expected (: From a pair of WR1101 I made 4 pieces of 900 mm each. Additionally, 4 ED1 DIN rails were needed (we happened to be at hand) and bolts with washers and nuts (then either M8 or M10, I don’t remember, they easily fit into the holes in the frame and in the DIN rail).

A small series of pictures below shows how I connected.
On 4 DIN rails

I bent the “ears”-clamps sticking out on them inward:

On the other hand, the second frame starts:

Next, the frames are brought together until they stop, and inside both frames the DIN rail is moved and installed in a position where some of the holes simultaneously coincide in both the frames and the DIN rail itself. The bolts holding the entire structure pass through these holes:

It turned out to be three bolts per joint. The washers, of course, need to be taken wider, but so that they fit into the “alignment” of the frame. Additionally, the joint was “framed” with the same DIN rails, placed everywhere: both between each left and right pillar, and between the front and rear, respectively. In short, it turned out to be a parallelepiped. Next, I placed the entire frame on prepared M10 studs behind the rear frames to the rear wall of the niche:

Although in general the frame turned out to be very rigid, I placed metal bearings under the front pillars in the spacer with the tie (they are a little visible in the photo with the terminals). There is no play in the front part of the frame left-right within a couple of mm, up-down and back-and-forth. After covering with plasterboard and overlays it will not be there at all.

That, in fact, is all I wanted to tell you about. Budget for 4 connections - 4 ED 1 rails and 12 sets of bolt + 2 washers + nut.

In addition to processing solid pieces of wood, it is often necessary to connect wooden parts into units and structures. Element connections wooden structures called landings. Joints in the structures of wooden parts are determined by five types of fits: tense, tight, sliding, loose and very loose fit.

Nodes - these are parts of structures at the junction of parts. Wooden structure connections are divided into types: end, side, corner T-shaped, cross-shaped, corner L-shaped and box corner connections.

Joinery joints have more than 200 options. Here we consider only the connections that joiners and carpenters use in practice.

End connection (extension) - connection of parts along the length, when one element is a continuation of the other. Such connections are smooth, jagged with spikes. Additionally, they are secured with glue, screws, and overlays. Horizontal end connections withstand compressive, tensile and bending loads (Fig. 1 - 5). Lumber is increased in length, forming vertical and horizontal toothed joints (wedge lock) at the ends (Fig. 6). Such joints do not need to be under pressure during the entire gluing process, since there are significant frictional forces at work. Toothed connections of lumber made by milling meet the first class of accuracy.

Connections of wooden structures must be made carefully, in accordance with three accuracy classes. The first class is for measuring tool high quality, the second class - for furniture products, and the third - for construction parts, agricultural implements and containers. The lateral connection by the edge of several boards or slats is called joining (Fig. 7). Such connections are used in the construction of floors, gates, carpentry doors, etc. Plank and slatted panels are additionally reinforced with crossbars and tips. When covering ceilings and walls, the upper boards overlap the lower ones by 1/5 - 1/4 of the width. The outer walls are sheathed with horizontally laid overlapping boards (Fig. 7, g). The upper board overlaps the lower one by 1/5 - 1/4 of the width, which ensures the removal of precipitation. Connecting the end of a part to the middle part of another forms a T-shaped connection of parts. Such connections have large number options, two of which are shown in Fig. 8. These connections (ties) are used when connecting the joists of floors and partitions with the piping of the house. Connecting parts at right or oblique angles is called a cross connection. This connection has one or two grooves (Fig. 3.9). Cross joints are used in roof and truss structures.

Rice. 1. End connections of beams that resist compression: a - with a direct half-wood overlay; b - with an oblique overlay (on the “mustache”); c - with a straight half-wood overlay with a joint at an obtuse angle; g - with an oblique overlay with a tenon joint.

Rice. 2. End connections of beams (extension) that resist tension: a - in a straight overhead lock; b - c oblique patch lock; c - with a straight half-wood overlay with a joint in an oblique tenon (dovetail).

Rice. 3. End connections of beams that resist bending: a - with a straight half-timber overlay with an oblique joint; b - with a straight half-timber overlay with a stepped joint; c - in an oblique overhead lock with wedges and a tenon joint.

Rice. 4. Joining by cutting with reinforcement with wedges and bolts.

Rice. 5. End connections of beams working in compression: a - end-to-end with a secret hollowed-out tenon; b - end-to-end with a hidden insert tenon; c - with a direct half-wood overlay (the connection can be strengthened with bolts); Mr. direct half-wood overlay secured with wire; d - with a direct half-wood overlay secured with metal clips (clamps); e - with an oblique overlay (on a “mustache”) secured with metal clips; g - with an oblique overlay and fastening with bolts; h - marking of the oblique overlay; and - end-to-end with a hidden tetrahedral tenon.

Rice. 6. End extensions of the milling scheme during end gluing of workpieces: a - vertical (along the width of the part), toothed (wedge-shaped) connection; b - horizontal (according to the thickness of the part), toothed (wedge-shaped) connection; c - milling of a gear connection; d - sawing out a gear connection; d - milling of a gear connection; e - end connection and gluing.

Rice. 7. Joining the boards: a - on a smooth reveal; b - on the insert rail; c - a quarter; g, e, f - in the groove and ridge (with various forms groove and tongue); g - overlap; h - with a tip in a groove; and - with a quarter tip; k - with overlap.

Rice. 8. T-shaped connections of bars: a - with a hidden oblique tenon (in the paw or in the dovetail); b - with a straight stepped overlay.

Rice. 9. Cross connections of bars: a - with a direct half-wood overlay; b - with direct overlay of incomplete overlap; in - with fit in one nest

Connections of two parts with ends at right angles are called corner connections. They have through and non-through tenons, open and in the dark, half-dark on the overlay, half-tree, etc. (Fig. 10). Corner joints (ties) are used in window frames, in joints of greenhouse frames, etc. A tenon joint in the dark has a tenon length of at least half the width of the part being connected, and the depth of the groove is 2 - 3 mm longer thorn. This is necessary so that the parts to be joined can easily mate with each other, and there is room in the tenon socket after gluing for excess glue. For door frames, corner angles are used. finger joint in the dark, and to increase the size of the surface to be connected - semi-dark. Double or triple tenons increase the strength of the corner joint. However, the strength of the connection is determined by the quality of its execution. IN furniture production A variety of corner box connections are widely used (Fig. 11). Of these, the simplest is an open end-to-end tenon connection. Before making such a connection, tenons are marked at one end of the board with an awl according to the drawing. By marking the side parts of the tenon with a file with fine teeth make a cut. Every second cut of the tenon is hollowed out with a chisel. To make the connection precise, first saw and hollow out the tenon sockets in one part. It is placed on the end of another part and crushed. Then they saw through, hollow out and connect the parts, cleaning the joint with a plane, as shown in Fig. 11.

When connecting parts “mustache” (at an angle of 45°), the corner binding is secured with steel inserts, as shown in Fig. 12. At the same time, make sure that one half of the insert or fastener fits into one part, and the other half into another. A wedge-shaped steel plate or ring is placed in the milled grooves of the parts to be connected.

The corners of the frames and drawers are connected with a straight open through tenon joint (Fig. 3.13, a, b, c). With increased quality requirements (the tenons are not visible from the outside), corner knitting is performed using an oblique connection in the dark, groove and tongue, or an oblique connection to the rail, as shown in Fig. 13, d, e, f, g and in Fig. 14.

A box-shaped structure with horizontal or vertical transverse elements (shelves, partitions) is connected using corner T-joints, shown in Fig. 15.

In the connection of elements upper belt wooden trusses with the bottom use corner notches. When connecting truss elements at an angle of 45° or less, one notch is made in the lower element (tightening) (Fig. 16.a), at an angle of more than 45° - two notches (Fig. 16.6). In both cases, the end cut (cut) is perpendicular to the direction of the acting forces.

Additionally, the units are secured with a bolt with a washer and a nut, or less often with staples. The log walls of a house (log house) made of horizontally laid logs in the corners are connected by a “claw” notch. It can be simple or with an additional spike (paw with a pit). The cutting is marked as follows: the end of the log is hewn into a square, to the length of the side of the square (along the log), so that after processing it turns out to be a cube. The sides of the cube are divided by 8 equal parts. Then 4/8 of the part is removed from one side from the bottom and top, and the remaining sides are done as shown in Fig. 17. To speed up the marking and accuracy of making cuts, templates are used.

Rice. 10. Corner end connections of workpieces at right angles: a - with a single opening through tenon; b - with a single through hidden tenon (in the dark); v-s single a dull (not through) thorn in the dark; g - with a single through semi-secret tenon (semi-dark); d - with a single blind spike in semi-darkness; e - with a triple open through tenon; g - in a straight half-tree overlay; h - through dovetail; and - into the eyes with trimming.

Rice. 11. Box corner joints with straight through tenons: a - cutting out tenon grooves; b - marking the spikes with an awl; c - connection of a tenon with a groove; d - processing of corner joints with a planer.

Rice. 12. Corner end connections at right angles, reinforced with metal inserts - buttons: a - 8-shaped insert; b- wedge-shaped plate; c- rings.

Rice. 13. Box corner joints at right angles: a - straight open through tenons; b - oblique open through spikes; c - open through tenons in a dovetail; d - groove on the insert rail butt; d - in groove and tongue; e - on plug-in spikes; g - on dovetail spikes in semi-darkness.

Rice. 14. Oblique (mustache) box joints at right angles: a - with oblique tenons in the dark; b - oblique connection to the plug-in rail; c - oblique connection to tenons in the dark; d - an oblique connection, reinforced with a triangular strip on glue.

Rice. 15. Direct and oblique connections of workpieces: a - for a double connection in an oblique groove and ridge; b - on a straight groove and ridge; c - on a triangular groove and ridge; d - on a straight groove and a ridge in the dark; d - for straight through tenons; e - on round insert tenons in the dark; g - on a dovetail spike; h - on the groove and ridge, reinforced with nails.

Rice. 16. Nodes in truss elements.

Rice. 17. Interfacing logs of the log house walls: a - simple paw; b - paw with a wind spike; c - marking of the paw; 1 - wind spike (pit)