For the use of various wood compounds in the field of construction, not only tools are indispensable, but also without appropriate experience. That is why for inexperienced craftsmen such connections are not always obtained accurately. One of the best options is for professionals to use a variety of array fasteners that are made of metal.

Many surviving architectural monuments made of wood were built without nails, using only an axe. This fact causes true pleasure to this day. However, centuries later, fasteners erected from metal, used to build solid wood structures, have changed radically, for this very reason it is pointless to repeat the experience of our ancestors today.

It is preferable to erect quickly and without difficulties. Let's talk in more detail about the fasteners offered by manufacturers, taking as an example the details that make it possible to simplify the connection of beams with floor logs or solid wall surfaces as much as possible.

Fasteners with perforation

When beams, as well as logs of the floor surface are hidden in the interior space, it is possible to connect them using beam shoes. This fastener for wood structures is suitable for fixing the array not only to wood, but also to concrete, brickwork. It is made from durable steel.

Manufacturers advise fastening such fasteners to the parts to be joined with special screws, and in case of excessive load, or fixing to stone material, use the holes for the necessary bolts. In addition to anchor shoes, today you can purchase special clamps, and much more.

tenon groove

This galvanized wood fastener consists of a tenon part and a groove part, which are joined together to ensure better transmission of horizontal as well as vertical forces.

The connection can be visible or hidden; for this purpose, steel parts are recessed in advance into special grooves.

Reiki three-dimensional

A modern Italian company produces fasteners that are placed perpendicularly and vertically at an angle, using T-type rails, created by extrusion from a high-strength steel alloy. They are produced in several modifications, provided for multi-level loads.

The fastening system must be selected according to the size range of the cross-sections of the combined beams and the dynamic and static loads acting on them.

During installation, the rack base is attached to the beam by means of self-tapping screws. Then, on the end part, attached to the base of the log beam, a groove is created of the same size as the rack shelf. In the absence of perforation, the shelf is equipped with a lag and the connection is fixed with self-tapping screws.

Hidden details Hedgehog

These connectors are steel washers, the base of which is equipped with holes drilled under the slope. These holes are for self-tapping screws. There is a threaded hole in the center of the washer into which a pin is inserted. Its free end is threaded into a special hole and fastened on the back side of the beam with a part with a washer.

The created connection works perfectly not only for pulling, but also for shearing. With excessive load in the area of ​​\u200b\u200bthe end part of the log, it is possible to install several elements at the same time.

Fasteners with complex thread

Unusual self-tapping screws, which make it possible to save time, money, since this option does not require metal parts. The self-tapping screws are threaded to help create a high degree of pull-out resistance, as well as being tightly screwed into an array that completely changes their traditional function.

In this case, the work of the screws is exclusively for pulling out, which gives them the opportunity to take most of the effort that falls on the connection. So, you can fasten elements at an angle, combine parts, minimizing their deflection, as in the photo of wood fasteners below.

Self-tapping screws for special purposes

Using such elements, rather massive wooden products are fastened. The hat has milled ribs and is easily recessed into the product, while the tip is created like a drill. In the middle of the screw, the cutter makes a larger hole, helping to pull the element as tightly as possible.

Self-tapping self-tapping screw will be useful for fastening door frames, window openings, solid wood sheathing to wood, metal. The self-tapping screw is screwed directly into the box, as well as the wall surface located behind it, or a power part.

The self-tapping screw acts as a weather vane for high-quality fastening of solid wood sheathing to a base made of steel. It has a tip in the form of a drill and wings placed above it to expand the hole in the tree.

When drilling metal products, the wings break. As a result, having made a thread in a metal part, the self-tapping screw fits snugly against it, while the element from the array is attracted to the metal by the cap.

Photo of wooden fasteners

It often happens that we need to fix a different number of parts, bolts or structures on the wall. For this purpose, a lot of different fastener options have been created. For example, for wood, self-tapping screws are usually used, and for concrete, cement or brick, you need to use a special tool called an anchor bolt.

The use of such mounts makes it possible to fix rather heavy things on walls and ceilings. An example is a water heater, a sports wall or a satellite TV dish on the roof or wall of the house. In itself, such a mount is an internal bolt, a nut at the end and a body. The bolt also has a plastic gasket that prevents water from penetrating inside and destroying the bolt.

The main types of such bolts

The first, most popular of which is the installation of an anchor bolt with a nut. Such a bolt consists of a stud and a nut with a body, which is completed with a washer, after fixing such an anchor, the stud will protrude somewhat beyond the edges of the bolt, which allows increasing its length. This type of fastening is intended for use in cement, concrete and concrete partitions, solid brick or stone. In all other materials, it is better not to use such fasteners.

The second type is an anchor bolt with a hook. Such fastening will be necessary for hanging removable items or heavy structures, as well as temporary fastening of chains, cables and ropes to brick, concrete or other surfaces. Such a bolt consists of a collet and a stud, in one part and in the other, which is also placed in a sleeve. This type of fastening is excellent for concrete surfaces, natural stone and solid bricks. All other materials that have a lower density will not work. The last, most common type of fastening is the anchor bolt with a ring. It is used to hang fixed heavy structures, such as gates, or to secure cables, chains and ropes to brick, concrete or natural stone surfaces. Such an anchor is made like a stud with a ring not welded on the end. At the other end there is a collet with an outer shell and a thread. The anchor is made of galvanized steel and is suitable for installation in natural stone, concrete or solid brick.

Hello. Please answer, what is the diameter of the holes for anchor bolts in a wooden beam (the size of the hole should be the same as the diameter of the bolt or less)? Thank you in advance.

Nikolay, Penza.

Hello, Nikolai from Penza!

Anchor bolts are a universal tool for fastening parts of various designs. They are used both in combination with stone, metal, and in wooden structures.

As a rule, an anchor bolt is a bolt with a wrench head or a screw with a slotted (cross) slot for a screwdriver. Complete with such a bolt, a washer is most often used, which is placed directly under its head, a sleeve (otherwise a spacer sleeve) with one, two or four longitudinal slots, as well as a conical nut.

The principle of operation of an anchor bolt is that when its head is screwed in with a wrench, the cone nut moves along the thread and enters the sleeve, expanding it. Since the anchor bolt is placed in the holes of the fastened parts (in your case, in wooden beams), the sleeve fits snugly against the inside of the hole. Which to a large extent guarantees reliable fastening.

The presence of a washer under the head of the anchor bolt prevents the head from falling into the thickness of the wood.

The weak side of anchor bolts is that once fixed, they cannot, with rare exceptions, be dismantled. Since their components are deformed, and the thread is jammed.

The size of the hole that is drilled for the anchor bolt is usually made equal to the largest diameter of the inserted set. That is, the outer diameter of the sleeve (spacer sleeve) is measured with a caliper in its largest possible place. In this case, the entire system (bolt, washer, sleeve, flare nut) should not dangle relative to each other, but be slightly wrapped.

The anchor is inserted into the aligned holes of the fastened parts of the structure to the maximum possible depth, after which, with not very strong blows of the hammer, it is driven completely until the head with the washer stops against the surface of the wooden beam. After that, with a wrench or a screwdriver with an appropriate bit (or head), it is wrapped, as they say, to the fullest.

If the hole for the anchor bolt is made slightly smaller than the maximum diameter of the sleeve, then when the anchor is driven in, the thread may be jammed and it will be impossible to turn the bolt in the flare nut in the future.

And if the hole is too large, the sleeve with its outer surface may not catch on the inner surface of the hole, no matter how hard you turn the bolt.

All of the above does not negate the possibility of small deviations in the diameter of the holes (about 1-2 millimeters) from the diameter of the anchor set.

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Are anchors suitable for wood? How to securely attach a chandelier, hanging bed or other massive thing to a wooden beam with them? What other tools can be used when splicing wood structures? Let's figure it out!

Types of anchors

The word "anchor" is of Germanic origin, its main meaning is "anchor". Anchor fasteners are used when mounting a variety of products on a base made of wood or concrete.

There are several types of "anchors":

• spacers;
• persistent;
• adhesive;
• Bolt Molly.

The expansion anchor is held in the workpiece by friction. To maximize it, the rod installed in the hole is bursting with a plastic dowel or wedge with a thread inside.

The fixation of the thrust bolt is ensured by the ribbed or expanding part of it that has fallen into the base. This is how the fasteners used when installing heavy production plants on a concrete foundation are arranged.

Glue "anchors", as the name implies, adhere to the surface due to the sticky composition entering the void between the walls of the hole and the ribbed rod. Most often, the role of the adhesive mixture is performed by a polymer resin with a hardener.

The Molly bolt is used when hanging products on low-strength partitions made of GVL, chipboard, GKL and hollow bricks. In the process of tightening, Molly bursts the outer shell to the sides. As a result, there is a stop, extensively in contact with the base.

On a note: craftsmen often refer to adhesive anchors as “chemical”.

Now let's figure out which type of anchor bolts are suitable for various methods of fastening to wooden structures:

• The Molly Bolt can only be used on a surface that has a large area of ​​voids inside. That is, this method is only suitable for hanging relatively light objects on partitions made of boards, chipboard and lining;
• persistent anchors are used only in the process of creating a massive base. In the case of wood, this is the growth stage of the tree trunk, so such fasteners will not work for us;
• adhesive "anchors" can be used when working with wood, but this is not always advisable due to the high price of this product.

Important: large changes in humidity can cause a loss of adhesion between the body of the cured resin chemical anchor and the walls of the hole, because of this, the fastener will become unusable.

Based on the above facts, we can conclude that the anchor fastener for the tree must be spacer. However, another important factor should be taken into account here: depending on where the effort is directed, the strength of the wood can be different:

1. If the force vector runs parallel to the fibers, the material is more tensile;
2. When the force vector is perpendicular to the fibers, the destructive force will be many times less.

In simple terms, a tree is more likely to split if it is wedged between the fibers. At the same time, typical expansion fasteners produce a radial expansion force that can pose a risk to the wood substrate.

To reduce the bursting force, the masters resort to a simple maneuver:

• The wood itself is used as a dowel (wedging element);
• The hole for the rod is made only slightly smaller than the diameter of the ridges of its thread.

A design that matches this description is probably familiar to you - this is ... an ordinary screw!

Fasteners for wood

Fasteners suitable for connecting wood structures have several features:

Manufacturing options

The most common types of wood anchors are:

• hex bolt. It is used for fastening various brackets, plates and other flat and large structures with lugs to wooden bases;
• a stud with a nut, which is screwed in with a wrench (open-end or adjustable);
• a hook that plays the role of a strong suspension and is suitable for mounting chandeliers, hanging shelves, lanterns and so on;
• the ring performs the same functions as the hook. Its main distinguishing feature is that the ring prevents the suspended product from jumping off it when moving in space (for example, the ring can be used to create a children's swing). To attach a suspension structure to it, threaded or spring carabiners are used.

Installation

How to screw the anchor on wood with your own hands so that the fastening is as reliable as possible, and the base does not split?

The procedure in this case is not at all different from the technique of screwing in a large diameter screw:

• drill a hole at the attachment point. Its diameter must correspond to the diameter of the fastener along the thread cavities. So, a channel for a 10 mm rod must be made with an 8 mm drill;
• apply some liquid or solid soap to the threads for lubrication;
• screw the rod to full depth.

Important! The depth of the hole must correspond to the length of the rod. If the depth is less, then the bursting force on the wood will increase sharply, which can lead to cracks (if not immediately, then as the structure is used).

Other types of fasteners

In addition to "anchors", wooden structures can be connected using conventional bolts, studs, perforated plates and corners.

bolts

With their help, you can fasten two or more parts with an overlap (although the products to be joined must be thin enough). This fastening method is convenient to use when building up the rafters: two boards are overlapped for three of their widths and, through pre-drilled holes, are pulled together with two or three fasteners with nuts and wide washers.

hairpins

The stud is similar, but compares favorably with the presence of nuts on both sides. This fastener design allows you to tighten the fastener without turning the rod. This is useful if the stud is jammed by the connected parts. In addition, with a long rod, the force required to rotate it can be very large.

Corners and overlays

Perforated steel plates and angles should not be considered as competitors to "anchors".

These types of fasteners complement each other:

with the help of corners, it is possible to dock floor lag boards with beams or crowns without cutting (butt);
plates allow you to connect boards in the same way when splicing rafters or logs.

Important! To make such a connection reliable, choose a plate with a length of at least five times the width of the board. In addition, for screeding boards with overlays, it is worth using not “anchors” and not self-tapping screws, but bolts with wide washers.

Conclusion

Understanding how different types of anchors interact with wood will help you choose the best solution for your tasks.

Video: how to mount anchors

When building a house or renovating an apartment, it often becomes necessary to fix some heavy objects, whether it be a water heater for a bathroom, a wall bar in a children's room or a cupboard. And at the same time, a margin of safety is needed.

Ordinary dowels with plastic spacers can not always help in this matter, “heavy artillery” is needed here - these are anchors.

Anchor ("anchor" from the German language) - a bolt with a thread and a nut, the spacer part is also included in the kit, such fasteners are designed for attaching weighty structures. From the photographs, you can understand the features of the anchors, as well as their scope.

The history of the development of this fastener dates back to 1973, when the German Council of Experts began to work on the calculation of permissible anchor fasteners. And in 1998, a regulation was issued for the use of metal anchors in concrete ETAG 001.

In addition to solving household repair issues, anchor bolts are used in the construction industry, in connection with this there are many varieties of anchors, from simple ones - created for fixed structures, to specific ones - solving issues of constant pressure and bending on the fastener.

Advantages and disadvantages of anchor connections

The disadvantages include:

• Expensive cost;
• You need a lot of installation tools (punch, hammer, screwdriver, wrench);

Advantages:

• Increased margin of safety;
• Long service life;
• Increased security.

An important characteristic of anchors is the material of manufacture. Only high-quality structural steel is used to make anchors or strong aluminum-based alloys.

The material used for the manufacture of anchors must withstand loads and deformations. In addition, corrosion resistance is an important quality, because anchor connections serve for decades, therefore, brass, aluminum and stainless steel are used, which do not rust.

When installing anchors in wet rooms, choose them with a thicker galvanized layer.

Types of fastening anchors

Based on the nature of the fastened materials, the connection method is selected.

Chemical anchors

They combine the advantages of fasteners made of plastic and metal. Mechanism of action: chemical fast curing agents stick together, filling the entire area between the steel anchor and the base, thereby ensuring the strength and durability of the entire assembly.

Mechanical anchors

The assembly is held in place by opening a metal sleeve in the base material, thereby providing durable fastener performance.

Anchors for concrete structures

Anchors for hollow materials are the most elementary in terms of design features. They are held due to the adhesion of the sleeve with a hole in the wall or brick.

Drive-in anchors

Drive-in anchors are used in durable non-porous materials, they are hollow cylinders with a corrugated outer surface. When installing, they are driven in with a hammer into the prepared holes.

Inside the collet there is a thread into which fasteners with the corresponding thread are screwed. These anchors are made of steel and brass.

Wedge anchors

Wedge anchors are also designed for dense structures (concrete) and are fixed using the original moving wedge, which, when advanced, opens the petals of the sleeve when the fastener is tightened with a wrench. They are used for attaching medium-weight structures to walls.

expansion anchors

Expanding anchors are more often used for fastening heavy structures (metal doors). These are metal cylindrical bushings with grooves on the body. When tightening the nut with a wrench, the sleeve expands over the entire surface, and leans closely against the base material.

The advantage of these anchors is the ability to withstand heavy loads in the perpendicular and longitudinal direction.

Anchor adjustable in length

Anchor adjustable in length - this mechanism is used in the manufacture of wooden structures subject to shrinkage. Such fasteners are made of two plates, called support and reciprocal, they have holes for attaching to wooden elements.

An important point when installing an adjustable anchor is to match the size of the counter plate to the saw cut of a wooden beam. And as a rule, all positions where the anchors will be located are determined at the design stage.

Fasteners for hollow materials

Double-spaced anchors are metal products consisting of steel bushings put on a stud. When tightening the nut on the outside, the bushings inside diverge, the sleeve is deformed over the entire surface, because the bushings diverge in different spacer zones, which ensures reliable fixation in the wall; anchors of this type are almost impossible to remove after installation.

Anchors "Butterflies" with a spreading mechanism are suitable for light structures, they fasten interior details (pictures, sconces, shelves) to flat materials no thinner than 10 mm (drywall, chipboard, plywood).

The “wings” of the anchor open and are tightly fixed on the reverse side of the material. The reliability of the knot depends on the base into which the anchor is screwed.

When choosing anchor products, it is necessary to take into account: the characteristics of the material of both the anchor and the base surface, the weight of the fixed equipment, installation principles and, of course, stock up on the necessary tools.

Anchor photo