Knowledge of how to select a drill for a dowel is relevant in situations where it is necessary to drill a hole to fix this fastener in it. Dowels are used in cases where it is necessary to fasten various objects to the wall surface - furniture elements, photographs, paintings, etc. The reliability of the fastening will largely depend on how correctly the drill is selected to create the hole in which the dowel will be placed.
What to consider when choosing a drill for a dowel
Selecting a drill to create a hole in which the dowel will be fixed should take into account:
- the material from which the wall itself is made, as well as its finishing;
- expected loads of the fastener.
You should also choose a drill depending on the diameter of the fasteners used. On the outer surface of factory-produced dowels, as a rule, there are markings that allow you to correctly select drills of the appropriate diameter for them.
Table 1. Selection of drill and screw for dowel
It is important to know not only how to choose a drill for a dowel, but also how to drill a hole correctly. If it is necessary to drill a hole in the wall for a dowel, the diameter of which is 10 mm, then first use a drill with a diameter of 8 mm and an impact drilling mode. After the hole is drilled, the tool is replaced with a drill with a diameter of 10 mm and is used without using the impact drilling mode. This approach will allow you to get a hole in the wall of the required diameter with smooth and neat edges.
If you need to drill a concrete wall, it is better to use a Pobedit drill, which can handle such a durable material without any problems. Handpicked cutting tool must be at least 3 mm longer than the dowel itself. If you neglect this requirement, the dowel will not completely fit into the resulting hole, in the final part of which dust and pieces of crumbled material, as a rule, accumulate. In addition, the shape of the bottom of the hole may not match the shape of the tip of the fastener.
How to fasten light weight objects
In order to fasten objects that are light in weight, use a quick mounting dowel. It is usually used for fastening lightweight objects to building structures made of brick and reinforced concrete.
As a rule, to solve this problem, a dowel is selected, the diameter of which, like the transverse size of the drill, is 6 mm. In this case, the length of the fastening element depends on the thickness of the wall of the object being fixed with it. If you need to select a dowel for mounting on the wall, then its length should be at least 4 cm, but if the mounting is on the ceiling, you need fasteners at least 6 cm long.
Securing medium weight objects
Fixing objects of average weight is performed using impact-type dowels. In this case, the transverse dimensions of the dowels, as well as the corresponding drills, must be at least 8 mm. The dowel chosen for these purposes must go into the wall to a depth of at least 6 cm, and when attached to the ceiling surface - to a depth of 8 cm. To securely fasten an object of average weight (up to 10 kg) to the wall or ceiling, you must use 4 dowels at the same time.
Installation of objects with significant weight
To fasten heavy objects (furniture cabinets, shelves, TV stands, etc.), you must choose a dowel, also of the impact type. In this case, the diameter of such a dowel, as well as the transverse size of the drill, must be at least 10 mm. Such dowels are buried 6 cm into the walls, and 8 cm into the ceiling. For reliable fastening of heavy objects, as a rule, at least 6 dowels are used.
To fasten the horizontal bar and ladder, anchor bolts are used, the diameter of which must be at least 8 mm. Such bolts are buried 6 cm into the surface of the walls, and 8 cm into the ceiling.
Types of anchor bolts
Anchor bolts used for fastening various items, are divided into three main types:
- anchor bolts with a nut, which after installation of the fastening element is tightened with a cap or open-end wrench(with the help of such bolts, hidden fasteners are performed);
- anchor bolts with a self-locking nut, which is tightened using a Phillips-type screwdriver (such bolts can be used for fastening in places that are visible);
- double-expansion anchor bolts are the most reliable fasteners that are used to fix even very heavy objects.
How to fasten on unreliable surfaces
Very often there is a need to fasten objects on unreliable surfaces, which include plasterboard walls, building structures in old brick houses etc. When performing fastening on such surfaces, the following recommendations should be followed.
- It is better to choose dowel elements from nylon, and their diameter should be 10–12 mm. The diameter of the Pobedit drill, with which the hole for the fastener will be made, should be 2 mm less than the transverse size of the selected dowel.
- Drilling must be done in one step, without changing the drill, and the impact mode should not be used so as not to destroy the walls of the hole being formed.
- If the loads are small, then you can use a dowel with a diameter of 4-5 mm.
- If the loads are average, then it is better to choose an insert with a diameter of 6-8 mm.
- For very large ones - 14-16 mm. For example, when scaffolding is assembled.
- screw length
- screw thickness
The anchor has a bolt with a wedge at the end (they are tightened with a nut).
The anchor wedge itself is a nut (the nut is tightened with a bolt).
- non-expandable - an area that does not take part in the installation process;
- spacer - a part that changes dimensions when connected.
Believe me, the choice of dowels is huge. Which one to choose in each specific case??
We offer for sale and maintain a constant stock of a wide variety of types of dowels. Here are some of the most common dowel designs:
Polypropylene dowel spacer (with mustache) is designed for fastening various elements using self-tapping screws and universal screws in concrete, brick, stone. Manufacturing material - polypropylene or nylon.
Expansion dowel(hedgehog type) is also designed for fastening various elements into a concrete surface and has unique spacers for better fixation. Made from polypropylene.
Drywall dowel "DRIVA", there are plastic and metal, they are intended to fasten various elements and structures in soft materials - plasterboard and gypsum fiber sheets (GVL), porous concrete, using self-tapping screws and universal screws.
This dowel is made from zinc-aluminum alloy or nylon. Metal Driva, thanks to its tip in the form of a feather drill, is usually installed without first drilling a hole for it. Large threads on the outer surface of the dowel body make it possible to screw it into the wall with a screwdriver.
Dowel nail designed for quick fastening of windows, metal profiles, various sheathing slats and guides, timber, baseboards, plywood, cable ducts, etc. in concrete, stone, brick. when you need to install them quickly and in large quantities. The dowels are equipped with a nail knurled for retention in the form of reverse cones. The dowel-nail structure is made of polypropylene or nylon, and the nail, respectively, is made of steel. The nail is hammered in.))
But in order to make the right and competent choice, call the office of our company, leading specialists will help you and give the most comprehensive information on the fastening conditions necessary for you.
Standard Nylon Dowel suitable for any wall and used with a self-tapping screw with a diameter of 2 to 16 mm. A hole is drilled in the wall corresponding to the diameter of the dowel, in which it is held thanks to directed tendrils, and when wedging with a self-tapping screw, the dowel is “tightly” attached to the walls of the hole.
Dowel for aerated concrete, for such a dowel, a hole corresponding to the diameter is drilled. The dowel is held in the hole by wedging under the action of the self-tapping screw and its spiral ribs.
Frame dowel It comes in lengths from 60 to 360 mm., of two main types - for a solid solid base and for hollow (slotted) and soft materials. The extended spacer part of the dowel ensures engagement with several jumpers in material with voids at once. Typically used for fastening window and door frames, as well as through a layer of plaster and thermal insulation, various cladding elements.
Remote(adjustment) dowel, secures the sheathing slats under the subsequent sheathing at some distance from the wall. Allows adjustment in the range from 0 to 3.00 cm relative to the base, the position of the sheathing slats during the fastening process due to the dowel and self-tapping screw of a special design, divided into 2 parts (1 - base, 2 - slats).
Universal nylon dowel necessary for attaching objects to a hollow wall or other base that assumes the presence of a hollow or empty space. In a hollow base, the dowel bulges and is thus fixed in it. In a solid base of concrete or brick, the dowel expands and simply comes into close contact with the walls of the hole. Used for fastening wooden blocks, suspended ceilings, metal slats, window and door frames, lathing for facing slabs, etc.
December 10, 2017
A dowel and a self-tapping screw are two elements that complement each other if the task is to connect some kind of rigid structure to a solid solid wall: concrete, brick, assembled from foam blocks, finished with plasterboard. If the wall were wooden, then you can do without a dowel, because the screws are easily screwed into soft wood, where they are firmly fixed. The selection of one to another is based on dimensions: the length and diameter of the screw and the length and internal diameter of the dowel. It will also be necessary to take into account the thickness of the material being fastened.
The situation when the wrong choice is made does not occur often, but such cases are known. If the selection was done incorrectly, for example, the internal diameter of the dowel was chosen smaller than the diameter of the self-tapping screw, then the latter simply breaks the first. If everything was done the other way around, then the fastener will dangle inside the plastic insert without releasing it, causing the strength of the fastening unit to sharply decrease. The same can be said if the end of the self-tapping screw does not reach the bottom of the dowel.
In general, you need to approach the selection process correctly. And for this you need to start with the dowel. The larger it is, the greater the load it can withstand. Here the loads are distributed relative to the size of the plastic insert.
But here it is necessary to take into account the density of the material where the fasteners will be inserted. The higher the density, the more loads the mount will withstand. Therefore inserted into concrete products Dowels with self-tapping screws can withstand the heaviest loads with their small sizes.
So, the dowel has been selected in size, now the self-tapping screw is selected for it. Here are just a few relationships.
Now we need to match the lengths to each other. The length of the dowel is selected according to its diameter.
How to choose the right drill for a dowel for fastening various objects
The main thing here is not to make a mistake, because according to the standards, several lengths fit one diameter. For example, a dowel with a diameter of 6 mm can have a length from 25 to 50 mm with a gradation of 5 mm.
As for the length of the screw, it depends on the length of the dowel and the thickness of the material being attached. It is taken into account that the thickness of the attached material depends on the density of the base to which it is attached. If fastening is carried out on a loose surface, then the thickness of the attached material should not exceed the length of the dowel by 35%. If the base is dense, then the thickness should not exceed 60% of the dowel length. You need to drill a hole in the supporting structure a little longer than the length of the dowel, and the self-tapping screw can be screwed in all the way. Even if its end pierces the insert, it’s okay.
How to choose a dowel for a self-tapping screw
For correct and high-quality fastening of various building materials using self-tapping screws, it is important to select a dowel that is suitable in size and quality characteristics.
Although the dowel is an auxiliary fastening element, it nevertheless plays a very important role in the reliability and strength of the structures being fastened.
Dowels are made from a wide variety of materials, it can be various types plastics (polypropylene, nylon, polyethylene, etc.), they can also be made of various metals - iron, brass, stainless steel, etc.
Eat different types dowels, which are intended for fastening in walls made of brick, wood, and plasterboard.
For example, a type “K” dowel is fixed in concrete:
Dowel type "T" is intended for fastening in walls made of weak concrete and brick:
The type "S" dowel is fastened in many materials from various bricks and concrete:
Dowel type "U" is a universal dowel made of polypropylene, which is attached to both solid and hollow materials very reliably:
The "KPU" dowel is a dowel made of nylon, very resistant to temperature changes and various mechanical deformations:
The "KPW" dowel is also made of nylon and is intended for plasterboard and wood-shaving materials, as well as for concrete and brick (solid and perforated):
The "KPX" dowel is used for fastening in solid building materials such as brick, stone, concrete, as well as in hollow blocks, etc.:
The "KPR" dowel is used for fastening in hollow building materials: aerated concrete, hollow block, lightweight concrete, window frames ah, etc.
The "KMG" dowel performs anchoring in aerated concrete and other materials:
The foam concrete dowel provides a strong connection with this porous material:
The Driva dowel is designed for fixing various lamps on plasterboard with a thickness of at least 9 mm:
The “Butterfly” dowel is a special dowel designed for fastening to drywall, gypsum board, chipboards and others. building materials thickness 10 - 12 mm:
All these dowels are tightly attached to the wall due to their special design, which includes a spacer part, the diameter of which is smaller than a correctly selected self-tapping screw.
Therefore, when the self-tapping screw is screwed into the dowel, the spacer part expands, forming a strong, reliable connection to the wall.
Below you can see a table that will help you choose the right screws and dowels in accordance with their length and diameter. This table also contains data on the drill diameter and drilling depth in each specific case.
To select a self-tapping screw for a dowel, you need to pay attention to two parameters:
The length should be such that the self-tapping screw, when fully screwed into the dowel, has a protrusion from the self-tapping screw that is several millimeters (3-7) less than the thickness of the material that needs to be secured, taking into account the fasteners you need (sunk, flush, or other)
The thickness of the screw should be such that the working surface of the dowel diverges in width, but in the meantime the screw itself rotates with a certain small force until the very end without applying much force.
Also pay attention to the thread itself, it should be just such that it can be screwed tightly into the dowel, since it is possible for the self-tapping screw to be pulled out of the dowel.
For fastening various building materials to building structures in modern construction Fastening with dowels and self-tapping screws is often used.
A self-tapping screw is selected for the dowel of a certain diameter that you have chosen, which, with a slight stretch, fits into the internal hole of the dowel, that is, the self-tapping screw must be smaller in diameter than the outer diameter of the dowel, by approximately 1.5 - 2 mm, and must be equal to the internal diameter of the dowel hole.
The length of the screw should be equal to or slightly greater, up to approximately 5 mm, the length of the dowel.
The hole for the dowel is drilled with the same diameter as the dowel you are using.
The depth of the hole is 5-6 mm longer than the dowel, so that the self-tapping screw is completely wrapped into the dowel, and its tip does not rest against the hole. building structure. Good luck.
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Which dowels are better
Which dowel to choose is a rather trivial question, which actually has a clear answer: you need to choose the dowel that matches the installation material and type of installation. How many times will a master curse a scrolling self-tapping screw when installing a cornice on a foam concrete partition of a house of the 1-LG-600 series? How many people have wrapped an unfortunate dowel with electrical tape, put a cable casing on it, put on a heat-shrinkable tube - and all to no avail!
Who would guess to put two or three pieces in a row and turn them all the way through so that they don’t turn? And how many people use a special expansion dowel for gas and foam concrete, not to mention the fact that few suspect, and even fewer know for sure, that such a dowel, it turns out, exists in nature! But the unified classification of dowels, reflected in any regulatory documents, just doesn’t exist in nature.
So here, in fact, everything is both simple and quite complicated at the same time. Let's try to figure out what kind of dowels there are in principle:
According to the operating principle:
1. Spacers, which are held in a hole of a certain diameter due to expansion when screwing in self-tapping screws - the ribs of the spacer dowel rest against the walls of the hole and wedge in it. They are intended for solid materials (concrete, reinforced concrete, asphalt, even wood and wood-based materials).
2. Anchor ones, which, in addition to wedging in the material, are also capable of deforming so that the back part of such a dowel cannot fit into the hole (anchor principle). Such dowels are intended for hollow and porous materials ( brickwork from hollow brick, aerated concrete, foam concrete, etc.), as well as sheet materials such as gypsum board.
By installation method:
1. Twisting - this long and awkward word speaks for itself and precisely defines the method of installation of this class of dowels. Tightening is done either with a screwdriver of the desired configuration, or with a similarly equipped screwdriver (details below).
2. Hammered - similarly, the method of installing such dowels is hammering, usually with a hammer or mallet, but sometimes with the help of other tools: for example, these can be pliers, wooden block, a fragment of solid brick or a piece of concrete, steel angle, etc.
They also separate through installation, in which part of the dowel is passed through the structure being fixed (has an elongated non-expanding part) and preliminary, in which the dowel is placed in the hole along its entire length (the most common type of installation).
According to the material of manufacture:
1. Plastic - made of polyethylene, polypropylene or polyamide (nylon).
2. Metal - made of aluminum alloys, brass, stainless steel.
By type of front part:
1. With a side (cuff) - when screwed, the side wraps around a screw (screw).
2. Without a side. True, you can get an effect similar to the side if you do not insert the dowel all the way, leaving about 3 mm outside.
By purpose, scope and design features:
1. Standard dowels for solid materials are the most common type of this type of fastener. Classic version It is made of nylon (polyamide), and most of all it is represented on the market by the Finnish company SORMAT (series NAT 5, NAT 6, NAT 8, NAT 10, NAT 12, etc.). In second place is the Swiss manufacturer MUNGO, whose dowels are painted in a characteristic red-orange color and are also made of nylon.
This is a fastener that is suitable in most cases for most materials.
How to choose a self-tapping screw for a dowel
However, nylon has one very unpleasant feature - at low temperatures its strength increases sharply, and viscosity decreases. Therefore, when working “at minus” in the open, there are frequent cases of ruptures of nylon dowels (especially when using dowel-nails), as well as cases of inability to screw a self-tapping screw or screw into them completely.
However, practice has shown that it is better to use a brittle nylon dowel than a viscous polyethylene one made at the lowest level of quality. As a last resort, you can use an industrial hair dryer, performing installation in a warm stream of air.
2. The dowel for aerated concrete and foam concrete has the ability to wedge in the hole, held in place by special spiral ribs. A hole for it is drilled according to the diameter of the core, and then the dowel is driven in with a hammer and a screw is screwed into it.
3. Frame dowels are available for both solid materials and soft or hollow ones. They are used when installing window and door frames, as well as for fastening cladding elements through a layer of heat or sound insulation, a plaster layer, etc. Frame dowels can cling to partitions in the material, for which they have an elongated spacer part.
4. The adjusting dowel allows you to secure the structure at a certain (up to 30 mm) distance from the base; consists of two parts, one of which is intended for the base, and the other for the attached structure; also comes with a special screw. Designed for fastening various battens under cladding with sheet and/or panel materials.
5. The universal dowel is convenient for fastening both to cellular, creviced materials such as hollow bricks, and to hollow gypsum plasterboard partitions and suspended ceilings of various types. It is designed as follows: when screwing in a screw, the dowel material seems to “remember” the presence of a hollow space around itself and, accordingly, is deformed in it. There is also a modification of the universal dowel with spring-loaded folding strips: the strips go inside the hole in sheet material together with the dowel, and then recline like spacer springs in spotlights, resting against the inner surface of the sheet.
6. The dowel for gypsum plasterboard and porous concrete (“posidriver”, “jet plug”) is used for static fastening of suspended structures, as well as paintings, etc. on walls and ceilings made of gypsum plasterboard, SML, MCL and similar materials. It is screwed into the base using a screwdriver or a screwdriver, since it has a “posidrive” (PZ) type slot in the front part, and in the “back side,” that is, the back part, there is a sharp point along the profile of the first drill, extending to a cone.
“Pozidrivers” (that’s what we called these dowels, from the bourgeois name “pozidrivers” painted on the boxes with “MUNGO” fasteners in which they were delivered to the site) are made of both plastic and silicon-aluminum alloy (silumin). A plastic dowel (“fiber jet”) is used only for fastening to gypsum plasterboard and similar materials, while a silumin dowel is used for gypsum plasterboard, gypsum, chipboard and cellular concrete. Self-tapping screws for them are included, but they are usually of lousy quality.
Plastic posidrivers can be mounted using the so-called. “drill-screwdriver” (this is an attachment for a screwdriver), since some of their modifications do not have their own drill, unlike silumin ones. True, this attachment is not easy to get.
7. The soundproofing dowel is placed in a special rubber shell that absorbs extraneous sounds.
8. Collet dowel - a cylindrical sleeve with an internal thread, usually made of brass (this alloy has the necessary flexibility and at the same time is durable). The inner part (which is threaded) has the shape of a cone, and deep notches are applied to the sleeve on the outer part. There are options made of sheet steel, carbon or stainless steel, including without thread, for example, HILTI HKD-S.
The hole for this type of fastener should be drilled along the diameter of its front part. Next, we clean the hole (unlike, say, the process of installing a nylon dowel, cleaning here is strictly required), install the collet into the hole (we hammer it in with a hammer or, better yet, a rubber mallet so as not to damage the thread). We tighten the screw/bolt - the sleeve expands thanks to the notches, preventing rotation, and it is secured in the hole. A collet dowel is used for fastening various types of suspended structures in solid materials (concrete, reinforced concrete, monolithic brick, wood, etc.).
Finally, disc-shaped dowels, used for fastening heat-insulating boards on the facades of buildings and structures, and the so-called dowel-nails, which are combined types of fasteners, stand somewhat apart (unlike the ordinary dowels discussed here, none of the parts of these types can be fully used in separation from the other).
Variety of fasteners
Today (and, indeed, in all centuries) when carrying out various repair construction or finishing works It is simply impossible to do without the necessary fasteners. And in everyday life, such fasteners are also useful - to hang a picture, secure a shelf, strengthen a cabinet, etc. There are a large variety various types fasteners that have different design features and are used to solve relevant problems, ranging from securing a board with an ordinary nail to installing a complex anchor with increased reliability.
Fastening baseboards, laying plank floors, installing door and window frames, installing plasterboard sheets on walls, installing suspended ceilings, manufacturing and assembling various types of internal and external stairs - this is not a complete list of areas of use of modern fasteners. The total cost of fasteners used during work is about 1% of the total budget for repair or construction work.
The correct selection of the necessary fasteners ensures long and reliable operation of the connections made. So let's look at their main types.
Self-tapping screws
Based on the name of this fastener, in most cases (but not all) it is capable of cutting the necessary holes and grooves in the material being fastened.
They are classified into the following groups:
1. By type of material being joined:
wood screws (smaller pitch);
metal screws (larger pitch).
Note that metal self-tapping screws are made of two types - self-drilling and those for the use of which you first need to make a hole in the metal. The first ones have a small drill at the tip, the dimensions of which are selected for the specific thickness of the metal. A prominent representative of the second type of self-tapping screws is fasteners for arranging plasterboard structures.
2. By size.
Naturally, the diameter and length of the self-tapping screw must be selected based on the specific conditions of its use.
3. As intended.
roofing fastening products. They have a wide cap with a press washer, which completely seals the hole to prevent moisture from entering. They are presented in a large assortment on the website http://ms37.rf/crepej;
self-tapping screws general purpose, for example, drywall screws.
How to choose a self-tapping screw for a dowel?
Anchors: application and types
Let us immediately note that today a large number of people are trying to use such fasteners completely for other purposes. For example, quite often they try to secure objects on brick walls with anchors. As a result, the product still does not hold up; large holes remain in the wall, not counting the wasted effort and time.
Once and for all, it must be noted that the anchor bolt and anchor pin can only be used for concrete surfaces, and in other soft materials they can simply be scrolled.
Types of anchors (by type of external part):
1. Mounting anchor.
This is a universal fastener.
2. Anchor hook.
Once secured, such anchors can be used to hang large objects.
3. Loop anchor.
You can attach something to the loop of such an anchor.
Types of anchors according to the design of the hidden part (expansion principle):
Anchor sizes can vary from the smallest with a length of 50 mm (diameter 6...8 mm) to 400 mm (diameter 22 mm).
Anchor installation:
Selecting the correct drill bit for the drill and drilling the hole. Note: if you choose an anchor with a diameter of 10 mm, then you need to make a hole exactly 10 mm. If, for example, you take 12 mm, then as a result the anchor will not be clamped, and, naturally, no amount of winding various materials around the anchor will help either.
Installing the anchor into the hole.
Clamping the anchor with an open-end wrench or screwdriver.
Rivets
They are the simplest fasteners for permanently connecting sheet iron, tin and other thin-sheet materials, such as plastics or leather. They provide high strength of the connection, however, such a connection can only be disassembled if the head of the rivet is cut off.
Rules for selecting thickness and length are usually indicated on the fastener packaging.
Dowels: types and applications
Today, hardware stores offer 3 main types of dowels:
1. Metal dowel.
A metal dowel is the simplest and oldest type of fastener. It can be mounted on almost any surface. But still, it is not advisable to use a hammer in every case; sometimes it is worth loading such a dowel into a cartridge, electric or pneumatic gun. Metal dowels differ from each other only in diameter and length.
2. Mounting dowel with plastic plug.
Mounting dowel is the most common type of dowel. It is manufactured in two versions, which differ solely in the shape of the plastic plug used (more specifically, the shape of its outer rim). In one case, the dowel is installed in a hidden position, but in the other case it is not (the plug of the second dowel is equipped with a mushroom cap).
Such mounting dowels are installed using a puncher (making holes) and a hammer (first the plastic plug is hammered in, and then its metal part). Note that, if necessary, the metal part of the dowel can be quite easily unscrewed from the plastic plug with a simple screwdriver due to the applied thread. The diameters of such dowels vary from 6 to 14 mm, and the length - from 35 to 250 mm.
3. Expansion dowel.
Scientifically it is also called “Bierbach dowel”.
This fastener is made entirely of metal and consists of 2 wedges, which are movably connected to each other by a special washer on one of them. It is mounted in a pre-made hole, where it is wedged with a hammer blow. This is the best option for installing suspended ceilings.
Dowel-screw
A dowel screw is a type of fastener used to secure certain parts, structures, and individual objects in solid solid surfaces.
Features of using dowel screws
Dowels secure self-tapping screws, bolts and screws in the structure. The specificity of the work of the dowel-screw lies in the process of rapid friction, when the dowel steams the screw, nail, screw. The device of the product is indicated by two elements:
Some types of dowels are available with a cuff that prevents the product from falling into the hole. The fastener design is held inside the hole due to tightly pressed walls or due to differences in modification.
Previously, installers used wooden plugs to secure elements. Today, a wide range of dowels is produced (in accordance with GOST standards) intended for use in tandem with any materials. For the manufacture of fasteners, metal and plastic (polypropylene, polyethylene) are used. The most popular is the quick universal nylon dowel. Installation is carried out using the impact method. Such dowels together with self-tapping screws can be used to organize fastening, regardless of the wall material.
Metal and plastic dowels are equally suitable for drywall. The product is intended for mounting the necessary elements on the surface of gypsum fiber, drywall, and porous concrete. Skirting boards, windows, and sheathing are secured with a nail dowel-screw. This dowel comes with a knurled nail. The facade dowel, used to secure and hold the insulation, is equipped with a wide hexagonal mushroom-type head. Design features provide the necessary insulation of connections, preventing the ingress of moisture and dirt. To fasten window frames and door frames, a frame dowel with a countersunk screw (screw) is used. The dowel-clamp, used for fastening wires and pipes to foam concrete, concrete, brick, is characterized by simplicity, convenience, and reliable installation without the use of additional fasteners.
The dowel screw is one of the most common fasteners. Depending on the characteristics of the load, the nature of the base, and the type of fastening itself, a certain type of dowels is selected.
How to choose a drill for a dowel
It is imperative to determine which screws, nails, screws are suitable for the selected dowel (if the dowels are not equipped with screws). Along with the dowels, the kit includes an installation diagram and recommendations for selecting the appropriate screw. For the right choice dowel, it is necessary to take into account the diameter, length of the screws, and the thickness of the element mounted on the dowel.
A dowel-screw is a fastening element used to fix various products in a solid base. The operating principle is based on the frictional force that occurs when a screw is screwed into a dowel.
Brief historical background
The name of the inventor of the dowel and the date of its invention are unknown. But January 14, 1913 is the day the Englishman John Joseph Rawlings received a patent for this fastener.
The first devices of this kind were made of wood. Today, polyethylene, polypropylene and metal dowels are produced.
In addition, the use of nylon dowels is widespread - their use can solve many problems. These fasteners, complete with screws, are appropriate to use when working with any material.
Description
Nowadays, not one renovation work cannot be imagined without the use of dowels. There is always a need to attach something to a wall or ceiling surface. Only if the walls and ceiling are made of wood, you can use nails and a hammer. In all other situations you cannot do without dowel fasteners.
There is a wide range of similar products on sale, differing in the material of manufacture and method of holding. In addition, the weight and size of dowel screws can be very different.
The mounting dowel can be not only polypropylene, but also nylon. The use of the former is possible only in interior decoration, since sub-zero temperatures promote the formation of cracks on them. Nylon fasteners are equally suitable for both indoor and outdoor use.
The expansion dowel is used when fastening structures to hollow blocks, concrete and brick. Fixation occurs with the help of special antennae. They securely hold the dowel and prevent it from turning. There are individual species dowels intended for a construction gun. Despite the different installation method, they are quite effective.
Specifics of the dowel-screw
As you can see in the photo of the dowel-screw, it can be either with or without a locking collar. The collar dowel is usually made of nylon. It is used in outdoor installation work. Stoppers hold the fastener, preventing it from falling into the hole.
The fastening element without a shoulder is made from polyamide. His distinctive features are through hole, longitudinal ribs and non-expandable top. This design solution greatly simplifies screwing in the screw, increasing the degree of expansion of the dowel.
And the fixed top protects the plastered surface from cracks. In addition, fasteners without a shoulder are resistant to precipitation and their service life is much longer.
is a specialized fastener used for installation and fastening different designs to the walls of buildings. The most popular are plate-type products.
A dowel screw for drywall can be either plastic or metal. Its purpose is to fix products on plasterboard or gypsum fiber sheets and porous concrete.
Metal fasteners do not require pre-drilling holes - they have a feather drill at the end, and the spacers are equipped with threads. Installation of such a dowel occurs using a screwdriver.
The principle of operation of a universal dowel-screw in a thick wall is similar to the principle of operation of a conventional expansion screw. If the wall is thin, then after passing through it the dowel is screwed onto a screw and tied into a knot, which makes the fastener as reliable as possible.
The scope of application of the mounting dowel-nail is the quick installation of double-glazed windows, baseboards, sheathing, etc. The component part is a nail that has a knurled thread with a reverse cone for better fixation. To install it, you need a screwdriver and a hammer.
The purpose of the adjustment dowel is to fix wood products during interior design buildings. It allows you to do without the use of blocks and wedges to level an uneven wall surface.
For installation household appliances It is permissible to use the fasteners supplied with it. They are designed with the required safety margin. When choosing dowel screws yourself, you need to take into account the weight of the load and the material of the wall.
To attach a chandelier or suspended ceiling system, opt for special dowels equipped with deep transverse notches and spacer ribs.
Photo of dowel screws
Dowel– an auxiliary element for fasteners that ensures reliable adhesion of screws or self-tapping screws to the load-bearing base.
Dowels are made of plastic (polypropylene, polyethylene, nylon) and metal (iron, stainless steel, brass). The dowel can be roughly divided into two parts. Expansion (in the photo below is the left part of the dowel), it is responsible for the force of holding the screw in the material, and non-expansion (in the photo below is the right part of the dowel). The non-spacer part of the dowel is needed in order not to destroy the soft layer of materials. For example, you are installing a dowel into a plastered brick wall, if there is no non-expanding part, then when you tighten the screw around the dowel, the plaster will collapse. You hang a wall cabinet by the base through the chipboard, then the length of the spacer should be equal to the thickness of the chipboard plus the size of the plaster layer, it turns out to be about 30 mm.
The non-spacer part of the dowel can have a countersunk, cylindrical or round flange. The flange prevents the dowel from sinking into the hole of the material being fixed or into the wall. The use of dowels with a flange is convenient if the flange will not interfere.
When screwing the self-tapping screw, the spacer part of the dowel, which has an internal diameter much smaller than the diameter of the dowel, tries to move apart, but the wall material interferes and the plastic of the dowel is compacted under great pressure, connecting the self-tapping screw to the wall into one whole.
Dowels for fastening products on a plasterboard wall
For fastening objects on plasterboard walls, a special dowel is used, the end of which is equipped with cutting edges that act as a drill. To install such a dowel in plasterboard wall it does not require pre-drilling a hole, which allows you to fix an object on the wall in the absence of a drill or drill bit.
After installation, a self-tapping screw is screwed into the dowel without changing the geometry of the dowel. The dowel can be easily unscrewed from the drywall and reused.
There is another special dowel for attaching products to a plasterboard wall called Molly. Builders call it “Butterfly” because when screwing in the self-tapping screw, the spacer part of the dowel spreads out to the sides behind the inside of the drywall, taking the shape of the wings of a butterfly. This is due to the fact that at the end of the spacer there is a thickening into which a self-tapping screw is screwed, folding the spacer part of the dowel in half, firmly fixing the dowel in the plasterboard.
This dowel allows you to secure a product weighing up to 10 kg on drywall. Here is an example of attaching a large mirror to a plasterboard wall using a Butterfly dowel.
Choosing a dowel for a self-tapping screw
After the choice of the type of screw and dowel for mounting on the wall has been made, all that remains is to choose, using the data given in the table below, the standard size of the screw and the corresponding dowel. Decide on the diameter and depth of the hole for installing the dowel.
Due to the lack of an international standard for screws and dowels, many manufacturers produce according to their own internal standards. Therefore, it is impossible to accurately indicate all dimensions, but in the overwhelming majority of cases the dimensions coincide with sufficient practical use accuracy.
| Dowel selection table for the selected screw, hole size for the selected dowel | |||||
|---|---|---|---|---|---|
| Self-tapping screw | Dowel | Hole for dowel | |||
| Diameter, mm | Length, mm | Diameter, mm | Length, mm | Drill diameter, mm | Drilling depth, mm |
| 3 | 12, 16, 20, 25, 30, 35, 40 | 5 | 12, 16, 20, 25, 30, 35, 40 | 5 | 16, 20, 25, 30, 35, 40, 45 |
| 3,5 | 6 | 12, 16, 20, 25, 30, 35, 40, 45, 50 | 6 | 16, 20, 25, 30, 35, 40, 45, 50, 55 | |
| 4 | 5 or 6 | 12, 16, 20, 25, 30, 35, 40, 45, 50, 60, 70 | 5 or 6 | 16, 20, 25, 30, 35, 40, 45, 50, 55, 65, 75 | |
| 4,5 | 6 or 8 | 16, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80 | 6 or 8 | 20, 25, 30, 35, 40, 45, 50, 55, 65, 75, 85 | |
| 5 | 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100 | 6 or 8 | 16, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100 | 6 or 8 | 20, 25, 30, 35, 40, 45, 50, 55, 65, 75, 85, 95, 105 |
| 6 | 8 or 10 | 40, 45, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200 | 8 or 10 | ||
| 8 | 40, 45, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200 | 10 or 12 or 14 | 40, 45, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200 | 10 or 12 or 14 | 45, 50, 55, 65, 75, 85, 95, 105, 130, 150, 170, 190, 220 |
| 10 | 12 or 14 | 40, 45, 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200, 220, 240, 260 | 12 or 14 | 45, 50, 55, 65, 75, 85, 95, 105, 130, 150, 170, 190, 220, 230, 260, 280 | |
You need to use the table as follows. Let's say you need to hang bookshelf with a maximum possible weight of 100 kg with fastening on two hinges on brick wall. Since the shelf will be suspended by two screws, the load on one screw will be 50 kg. Choose from the table a self-tapping screw with a universal thread, with a hemispherical head, 6 mm in diameter, and at least 80 mm in length. A standard, simplest dowel will do. From the table we see that there is a self-tapping screw of this standard size; a dowel with a diameter of 8 or 10 mm and a length of 80 mm is suitable for it. Since we have a drill with a diameter of 8 mm, we choose a dowel also with a diameter of 8 mm. To install it, you need to drill a hole with a diameter of 8 mm to a depth of 85 mm.
Making dowels from scrap material
A furniture dowel can be successfully used as a dowel. It is made from hardwood. Diameter 8 mm, length 40 mm, with longitudinal ribs. Previously, in the manufacture of furniture, fastening with dowels was widespread.
Sometimes there is an urgent need to fix an object on the wall, but there is no ready-made factory-made dowel at hand. In this case, you can plan it yourself from any dry piece of wood. A chair or stool leg will do. This was always done before, for the reason that there were no plastic dowels on sale. It is advisable to chamfer one side of a homemade dowel to make it easier to hammer into the wall.
In order to screw a self-tapping screw into a wooden dowel, after driving it into the wall, it is necessary to drill a hole in its center with a diameter slightly smaller than the diameter of the threaded part of the self-tapping screw.
A good dowel can be made from a television cable in which the central core is insulated from the braiding with polypropylene by cutting a piece of it to the required length. To do this, you need to remove the outer insulation and shielding braid, and remove the central core. Next, cut the cut piece of insulation in half by a third of its length. In the uncut part, drill a hole equal to the diameter of the screw. It is advisable to make notches on the outside of the dowel with a soldering iron so that the dowel does not rotate in the wall when tightening the screw.
The result will be a dowel no worse than an industrial standard. True, there is a lot of fuss, but if you only need a few, then it makes sense to make it yourself.
Sometimes unexpected things happen when drilling a hole in a wall. The drill, due to the heterogeneity of the wall material or if it fails to hit a joint of bricks, does not drill a hole very accurately, and it is even much larger than a dowel. The dowel dangles, and in this case the screw will not hold it in the wall. Sometimes the wall is very loose and a large piece breaks off. But there is a simple solution that I have been using since time immemorial.
An aluminum or copper wire with a diameter equal to the thread pitch of the self-tapping screw or screw is wound around the screw. The result is a metal dowel with threads. Since I came across a dowel with a two-start thread, I wound the wire in two starts. The self-tapping screw can be easily screwed into and out of such a wire dowel. To prevent the wire dowel from turning in the wall, you should use a file to make edges on it on the sides.
The dowel is mounted into the wall as follows. A solution of cement, alabaster, gypsum or other similar mortar is diluted, the drilled hole is filled and a wire dowel with a self-tapping screw screwed into it is inserted until it sinks into this solution. If it is difficult to insert, you can tap it with a hammer. After the solution has hardened, you can unscrew the screw and hang the required item on the wall. It will hold securely.
Sometimes it happens that a hole drilled in the wall with a drill of a given diameter does not ensure a tight fit of the dowel and when screwing the self-tapping screw into the dowel, it turns. In this case, you can use the composition “Liquid Nails”. From the tube, the drilled hole in the wall is completely filled with the solution and a dowel is immediately inserted into it. After half an hour, you can safely screw the self-tapping screw into the dowel. It will hold tight.
Using liquid nails, using the technology described above, you can also securely fasten a standard plastic dowel in a wall made of porous material, such as foam concrete.
There are times when the dowel cannot be completely driven into the hole, and it protrudes a little, but cannot be removed. The protruding part must be removed. It can be cut down with a hacksaw blade.
To prevent damage to the wall covering, just take a small sheet of sandpaper, make a hole in it with a diameter equal to the diameter of the dowel, place it on the dowel with the sandy side facing the wall and carefully file it away. The wall covering will remain intact.