Make from a sheet of plywood. How to bend plywood sheets? Folding of layers during their gluing

Few people know that plywood bending is a very common operation in carpentry, more fewer craftsmen familiar with correct technique execution. We propose to consider the features of this material and its behavior during bending, as well as the basic techniques and devices for bending plywood at home.

Features of the behavior of plywood during bending

The veneer from which plywood is made is nothing more than a set of elongated fibers. They are rigid and durable, the space between them is filled with a soft binder. To give the sheets extra strength and compensate for warpage in the plywood layers, the veneer has a different grain direction in adjacent layers. Due to this, plywood is a rigid material that is difficult to bend.

Usually, plywood with an even number of veneer layers is used for bending, that is, it does not have a predominant grain direction. Otherwise, the direction of bending should be calculated across the minimum number of longitudinal fibers, or vice versa - along, if the requirement for increased strength is imposed on the part.

The thinner the plywood, the easier it is to bend. Sheets with three layers easily bend across the fibers of the outer layer, even when cold

When the fibers are parallel to the fold line, they do not interfere with the curvature of the plane. However, the layers located across experience significant loads. Characteristically, the fibers can stretch quite strongly, the necessary conditions for this are provided by their softening due to heating or moisture.

At the same time, the layers located on the inner radius of the bend experience a compressive load, which is not compensated by the elasticity of the material. With sufficient steepness of the bend, folds may form on its inner side. Sometimes the stress at this point is high enough to cause delamination—rupture of the adhesive layer or even of the fibers themselves. This characteristic behavior can be compensated for by a number of techniques, which this article is devoted to.

Necessary tools and equipment

As always, it will not be possible to do without high-quality equipment and tools. Since the main technology involves softening the sheet, shaping it, and then drying it in an immobilized position with taking shape, then at least a set of clamps is needed for bending. Ideally, there should be at least a dozen of them, but you can also bend plywood in stages, rearranging the fasteners.

In this case, along each line across the bend, the workpiece is fixed in three places: at the highest point of the radius and along the edges. In other words, with due diligence, you can get by with six clamps, but keep in mind that the accuracy of observing the dimensions of the finished part may be significantly lower than required.

Bending of plywood is almost always carried out according to templates. The exception is sheets of arbitrary radius, which are pre-bent before sheathing frame structures. For stair risers, chairs, armchairs and other pieces of furniture, the shape of the bent parts is known with high accuracy. Therefore, first it is required to make a spatial figure, to which the softened sheet will be attached for the time of drying and taking the required shape.

There are quite a few types of equipment that provide technological steaming or soaking of the glue. Humidity and temperature must be kept within acceptable limits, otherwise the adhesive may irreversibly lose its strength properties. At home and for one-time work, you can use heaters or films for underfloor heating. Wetting is best done not directly, but through a hygroscopic material that can accumulate and gradually release moisture, for example, through foam rubber, hemp burlap or felt. Also, all available devices for adjustable contraction and compression, such as sling straps or hand jacks, will not be superfluous.

Bending and soaking

When plywood is bent, important rule: The thicker the sheet and the steeper the bend radius, the more trouble will be required to soften. If we do not take into account the difference in the quality of plywood, then after soaking it is possible to achieve a bending radius of the order of 50-70 sheet thickness values. For tighter bends, other methods are recommended.

Soaking or steaming aims to soften the fibers in the veneer and make the adhesive more plastic so that after drying it will seize and securely fix the new shape of the part. At the same time, it is not permissible to oversaturate the wood with water, as well as sharp moistening and drying.

Small sheets of thin plywood are easiest to soften in a steam bath in an ordinary saucepan or in a juicer

For proper soaking, plywood must be kept under conditions relative humidity about 90-100% within 2 to 12 hours depending on the thickness. Periodically, you need to check if there is any delamination of the veneer at the ends or swelling in the center. From time to time, you can make attempts to bend. If the part takes shape relatively easily and no crackling is heard, then the plywood can only be thoroughly fixed until it dries completely.

For long parts, it is easier to prepare a box from any suitable material and after softening with steam from the steam generator

Wetting is recommended to be carried out when the plywood is laid on flat base and wrapped on each side with a layer of hygroscopic material. If at the same time the workpiece is not wrapped hermetically in a film, the humidity level should be controlled and periodically re-sprinkle the burlap with water. Heating up to 50-60ºС during wetting helps speed up the process and make the swelling of the adhesive reversible. It is absolutely impossible to allow plywood to overheat, so you should constantly monitor the temperature.

An alternative to softening by wetting is steaming the plywood. In this case, the sheet is fixed above a container with boiling water or not far from it. The disadvantage of this method is that the humidity rises throughout the room with concomitant condensation. The advantage of this method is the uniformity of softening and the low risk of waterlogging or overheating.

The vacuum table speeds up the process of softening the plywood, as well as the subsequent molding according to the pattern.

A softened sheet of plywood is wrapped around a pre-prepared frame structure or template, fixed at the key points of each bend. The plywood is pressed with clamps or self-tapping screws with a washer sequentially from one edge to another, while the more often temporary fasteners are installed, and the harder it is, the lower the likelihood that the part will change shape after being removed from the template.

Machining methods

In some cases, it makes no sense to resort to softening: for example, if the part is fixed on a sufficiently rigid frame, it will eventually take the desired shape due to natural changes in humidity. Another special case is the need to bend plywood under a radius less than allowed for certain thickness. Here it is worth using both softening of the sheet and its mechanical processing.

One of the processing methods before bending is to apply a series of cuts on the inside of the bend, parallel to the folding axis. Notches are best done with a cone cutter using a linear guide. The depth of the grooves should be no more than 3/4 of the thickness of the workpiece, while in the end at least two layers of veneer should remain intact.

If the cuts are turned inside the part and hidden from view, it makes no sense to calculate their number and pitch. Subsequently formed scars can, if necessary, be leveled with automotive putty and sanded to a smooth state. With due diligence, it is possible to calculate the reduction in the length of the arc during bending, using a known angle and bending radius. In this case, the number of notches will be equal to the quotient of arc reduction divided by the thickness of the cutter in the widest part of the lead. The required number of cuts must be evenly distributed over the entire bending radius.

Before fixing on the template, the cuts formed on the plywood are filled with a quality wood adhesive, such as Titebond 2. The protruding adhesive can be removed immediately with a spatula or sanded after drying. During the curing of the glue, the plywood is firmly fixed on the template.

It is also possible to facilitate the softening of thick plywood by perforating the workpiece. Holes with a diameter of 2-3 plywood thicknesses are made with a hole cutter or a Forstner drill in a checkerboard pattern with a step of about 80-100 mm between them. The degree of perforation may be greater, this is determined both by the bending flexibility of the plywood and the required final strength of the part. Naturally, this bending method is only suitable for hidden technological elements that do not form a finishing plane. If desired, the bent part can be sheathed on one or both sides with veneer or thin plywood, after softening them.

Template bending

In the simplest case, pieces of solid plywood having the shape of a bend profile can play the role of a template. Since most parts are bent along one contour on both sides, the templates are made in pairs, and then fastened together with spacers slightly less than the width of the part. Templates can also be different if you need to bend the part irregular shape, that is, curved along two axes.

Another type of template is a frame made of bars, which does not form an exact bend contour. In this case, the transverse bars are located at the pressure points, that is, on the most protruding and concave parts of the part profile. For fastening at intermediate points, you can add an arbitrary number of jumpers to the frame.

In the manufacture of the frame, it is necessary to take into account the type of clamping devices used. So, on plywood inserts, holes for jaws of clamps can be provided, and the frame itself can be equipped with additional stiffeners in the direction of pressure and tensile loads. If the part has a uniform bend along its entire length, it can be fixed without a frame, for example, by pulling it with a rope, a cable, a chain with a screw towbar or using sling belts.

Manufacturing of composite parts

It is possible to bend parts of a complex shape by alternately gluing layers of steamed veneer onto a workpiece of the required shape. In practice, this is a method to avoid fiddling with thick parts, because tight bends make it much easier to deal with thin sheets due to the small values of the allowable radius.

In the simplest case, the base is formed by a relatively thick perforated plywood sheet, the permissible bending radius of which is obviously lower than the required one. Such a part, most likely, will not have the necessary strength, therefore, subsequently it is “sheathed” with several more thin layers. In each case, it performs adhesive connection over the entire plane, the sheets are pre-softened so that they do not straighten the shape of the core.

Sheathing can be performed not only for the purpose of giving strength. In some cases, one or more outer layers have a purely decorative function. For example, thin sheets of veneer can hide traces of fastening the workpiece to the template, and plywood will mask perforations or cuts. It is also possible to paste the part with plastic, laminated veneer and other finishing materials that do not retain their shape well.

You can make a lot of useful things from plywood: furniture, shelves, partitions, various coasters, and more. However, in order for all this to be complete and beautiful, it is desirable to give homemade products different shapes, including round ones. In this case, the question arises: is it possible to bend plywood on your own and how to do it? To answer it, you need to know the existing technologies and methods of this process.

Stages:

	Plywood bending options. Features and nuances of the implementation of various methods.
	Choice of materials. In specialized outlets, plywood of different quality, size and thickness is sold, so it is extremely important to choose the best option.
	Bending the material by heating or notching the workpiece.
	Bending plywood with a large thickness. Features, options.
	Tools for doing work.

How to bend plywood at home: features

To properly bend plywood, moisture and heat are required. It is also possible to use a dry version of changing the shape of the tree. These methods are applicable to plywood of any thickness, however, it must be taken into account that the thicker the material, the more time is required to obtain the desired result. Scope of use bent plywood wide enough from construction works(lining spiral staircases, production of bases for arches, etc.) to the manufacture of bent furniture.

Choosing plywood for bending at home

Since this material is made by gluing thin layers of wood that are placed in different directions, the bending resistance increases. For this reason, thin plywood should be taken for work, as it has fewer layers. In the factory, its bending occurs on specialized equipment. The material is given the required elasticity by pre-treating it with steam.

At home, when repairing an apartment or a private house, structures that have a rounded shape are often needed (for example, when arranging an arch). They can be made with your own hands from bent plywood. Observing the technology, it is possible to obtain a high-quality product, despite the use of improvised means.

Plywood is sold at construction markets and at special points (specialty stores, supermarkets, etc.). When choosing, it is necessary to pay attention to the flexibility of the material, which is produced with a thickness of 3-4 mm. As a rule, it is used to create arches in doorways or when moving from room to room. After processing, a workpiece made of a similar material is fixed to the frame with screws.

IN Lately was visible on the market similar plywood Chinese production. It combines affordable cost and suitable quality. There are several ways that are used to create bent structures:

gluing;

cuts;

steaming;

various combinations of the above methods.

How to bend plywood at home (video): heating

This process can be done in the following ways:

immersing the workpiece in hot water (temperature - 60 ° C);

using superheated steam;

soaking in a warm liquid (rarely used, as it increases the time of the whole process).

If there are no conditions and the ability to bend the material using the above methods, epoxy glue can be used.

To apply the superheated steam technique, some experts create steam using a boiling kettle, less often an iron. But since the supply of steam must be constant, it is rather difficult to obtain steam in the required amount at home. For this reason, the first option is more popular for self-obtaining the required form of plywood.

Hot water should be poured into any open container - a bathtub is best, as its volume makes it possible to make bent products quite large sizes. The plywood blank is immersed in hot water for about 30 minutes. During this time, the wood will be able to crack down on the desired amount. A wet blank will easily change its shape, however, it should be borne in mind that if it is necessary to bend the plywood at a large angle, the whole process will need to be carried out in several stages:

first, bending should be performed at a small angle;

the material is again immersed in hot water;

after 30 minutes, the procedure is repeated, the bending angle increases;

the technology is repeated until the plywood acquires the desired shape.

But you need to take into account the fact that when soaking the workpiece, it can exfoliate. In the event that the plywood thickness is too small, 4-6 minutes may be enough to bend it. In some cases, an iron is used. The wetted material is ironed with a heated iron and immediately it is given the necessary shape, after which it must again be moistened and ironed with a heated iron.

In order to process a large sheet of plywood with steam on your own, there are far from always suitable conditions. In this case, to obtain the desired result, cuts are made in the material according to the type of strips that have the shape of a cone. For such work, a hand-held electric tool with a cutter installed on it is used.

Such cuts must be made very carefully, otherwise chips may form on the material.

For a workpiece with a thickness of 4-5 mm, the depth of such cuts should not exceed 2 mm, and their number directly depends on the steepness of the desired bending radius. That is, the larger it is, the more cuts will be required.

After that, the material is clamped on the template. The outer layer is pasted over with a strip of veneer, for which epoxy glue or even PVA is used. Plywood dries for about a day. The result is a hollow blank that can withstand fairly large loads.

Workpiece fastening. Video

In order for the shape of plywood to be stable, it must be fixed. This work can be done in several ways:

Any heavy object is placed at the bend, the ends are pulled together with a rope and supports are mounted under them.

The workpiece is fixed in the template with a cord, rope or tape.

The first method is absolutely clear, however, it will be necessary to control the design, since the plywood may slightly deviate from the required angle during the cooling process. The second method involves the use of a template, which can be used for almost any design with the necessary bend angles for the future part. Very often, a do-it-yourself fiberboard template is used. If you need to make an arch, then the steamed workpiece can be installed directly in place by clamping it with screws in the opening.

Steel templates can be used to fasten plywood. They bend with the wood. This technique is used for the manufacture of large-sized parts with a complex shape. A strip of steel is attached to plywood before lowering into the bath. After that, it is folded together with the blank sheet. Detachment occurs only after the absolute drying of the workpiece.

When using a load to fix the material, you should be careful and try to make it equal in width to the workpiece sheet. If this is not the case, then only the part of the plywood that was equal to the width of the load will be bent. Similar options are used for wood with a thickness of not more than 2 cm. In addition, it should be borne in mind that different varieties trees can bend in different ways.

The maximum effect can be achieved if the plywood was made of ash, walnut or beech. Experts do not recommend using oak, maple or larch blank sheets for plywood bending. As a rule, for wood it is possible to carry out compression by 25-33%, and tension by 1.5-2.5%.

How to bend thick plywood at home: video

If it was necessary to make a bent product from plywood with a thickness of 1.5 to 2.2 cm, then, as a rule, the option of cutting its surface with a cutter is used. The depth of the cut should not exceed half the thickness of the material sheet. It can reach a layer with the opposite direction, but not go deep into it. Otherwise, the workpiece will split. There is no exact definition for slot width as it can vary. The effect is quite possible when the bending angle on one side of the material is greater than on the other. This method can be used to create the walls of the boat.

The plywood is bent to the required angle and clamped into the mould. A strip of veneer is glued on top. Drying - 24 hours. The gluing procedure itself is possible both with cuts outward and inward - the level of rigidity of the part will not change from this. Just in the first case, voids are formed.

There is another option for obtaining products from thick plywood - gluing. In this case, a bent workpiece is cut with an allowance of 2-6 mm from a thin material. Simply put, a pattern is created, which is superimposed on the sheet in such a way that the plasticity and direction of the veneer alternate in the finished part to obtain the necessary rigidity. Plywood layers should be glued together using an epoxy composition, after which the workpiece is clamped with clamps for a day, which will give it the desired shape.

When the product is completely dry, it will need to be sanded and grind off all the irregularities around the edges.

To obtain a quality product, it is important to follow these recommendations:

for the safety of the received parts, the humidity level in the room should not exceed 9-11%;
the bend radius across the wood fiber should be smaller than along it;
steamed or soaked in hot water materials need to be bent while they are still warm.

In order to get enough complex bent structure it is better to turn to specialists with professional tools, experience and skills.

In construction, as well as apartment renovations, plywood is used only for the manufacture of flooring and formwork. reusable- so, at least, it happens in most cases. It's no secret that there are exceptions to any rule, and it may happen that it becomes necessary to make complex decorations from plywood with radius bends. In such a situation, you will certainly have to face the question of how to bend plywood? Together with the website, we will deal with ways to bend plywood on your own at home.

How to bend plywood photo

How to bend plywood: important points to know

The very first thing to understand when approaching the question of how to bend plywood is that this material is very unyielding, and in order to twist plywood into a ram's horn, you will have to work hard. In principle, everything is not so complicated as it might seem at first glance - in some cases, this process can even be quite simple.

This is one. In addition to the above, when approaching the question of how to bend plywood at home, you should also know other things. For example, despite its apparent strength, plywood is a fragile material, and if you start bending it without preliminary flirting, then it will probably break. Alternatively, cracks and delaminations will appear on the front layers, which pretty ruin the look of what you are doing. Even under factory conditions, the plywood bending process is preceded by preparatory work. In principle, preparation is the way to bend the material, which we will talk about later.

How to bend plywood with your own hands: various options

By and large, there are not so many options for bending plywood at home - just a couple. The first of the methods is used for small-format blanks (narrow strips up to 30 cm wide), and the second option can be used for large sheets. Let's talk about them in more detail.

In both cases, it is advisable to pre-prepare a template - this is, first of all, the accuracy of bending and, secondly, a guarantee that you will not bend the product. Unbending plywood back is not a very pleasant and thankless task, fraught with the appearance of cracks and breaks.

Curved plywood: what is it and what is it used for

Another option for making bent plywood is the technology of gluing thin fragments - instead of bending a thick sheet, you bend thin plywood, and then glue them together, achieving required thickness material. This is curved plywood - according to many craftsmen, this is the best option for self-manufacturing radial products from this material. Yes, bending thin sheets is not difficult, but ...

In addition, experience in carrying out work of this kind is required. Gluing plywood is not like patching a hole in a chamber. Requires special glue and so on. In general, this technology is not very suitable for one-time work due to the high cost of various fixtures and templates. Whatever one may say, but most the best option solving the question of how to bend plywood 10mm or more, the method of technological incisions remains - at least it allows you to do without precise templates.

And in conclusion, the topic of how to bend plywood, it remains to add only one thing - or rather, not even add, but once again state the fact that this is not a very rewarding business and, most importantly, laborious. For the sake of one detail, there is no reason to start with him. Another thing is if you want to mass-produce, for example, pioneer drums or standard-shaped arches. It is already in vogue here and not every company involved in their production can offer people affordable prices. Although, having tried to make one such product, you will understand why its price cannot be cheap.

Each craftsman should know how to bend plywood if he has to sheathe curved structures and decorative elements with it. It is required to learn the basic rules so that the material does not break when bent. The main difficulties lie in the tree structure and individual features plates.

More about the material

Before you bend plywood with your own hands, you need to familiarize yourself with such products in more detail. The product is a wood board obtained by gluing fragments of prepared veneer. To improve the strength properties of the fibers are arranged so that they are perpendicular to each other.

As for the number of layers, it may vary. Most often sheets consist of an odd number of layers of veneer. It is easiest to work with thin plates, but their scope is limited to decorative functions. For the device of arches or the formation of three-dimensional structures of a rounded type, in any case, thick sheets will be required, which are rather problematic to bend.

The process of soaking the elements

Masters who are thinking about how to bend plywood at home without unnecessary difficulties can be offered this option. It involves keeping the sheets above a tank of boiling water or placing them directly into a liquid medium. Soaking time will depend on the type of product as well as its thickness.

The method of keeping plates in water is more accessible and safe, so it is proposed to consider it in detail. However, during the work should be applied quality plywood. Bad sheets can delaminate quickly. Before starting soaking, it is advisable to lower a small piece of material into a container of water. If nothing happened to him, then you can dip whole fragments.

Step by step actions will look like this:

The workpiece of the required size is placed in water for a certain time. It is possible to understand that the product is ready for further transformations by conducting regular inspections. The plate will become pliable.
Soaking stops when the desired flexibility is reached. The sheet itself is moved to comfortable spot for work.
The workpiece is bent and fixed with screws in a certain position until completely dry.

IN living conditions It is recommended to combine humidification with steaming. With this option, only the outer layer is impregnated with water. The ferry is processing the place of the bend. It is best to bend the sheets along the wood fibers, then it will be possible to achieve the maximum effect.

Making frequent cuts on the bend

If the question is how to bend thick plywood, then in an efficient way will create numerous notches in the right place. To create cuts, you need a cutter. With its help, special stripes are made in a certain area of \u200b\u200bthe wood board.

When working, do not make deep cuts. They should reach a maximum of half the thickness of the sheet. The veneer layer located on the opposite side must not be damaged. Modern boats are often made from slabs rounded using this technology.

So, how to bend plywood by making gashes in it, step by step:

Frequent incisions are formed in a certain place.
The workpiece is attached desired shape by locking in the required position.
Using the composition of PVA or epoxy resin thick veneer is glued.
Fasteners are removed after about 24 hours.

The cuts are best positioned with inside. When gluing veneers on top of them, voids are formed. In case of careless operation of the manufactured structure, gaps may appear.

Technique for gluing thin sheets

Before bending thick plywood, consider using multiple boards. You can glue together a number of fragments, since it is much easier to bend them separately. However, when using low-quality glue, there may be problems with delamination of the product already at initial stage operation.

First, whole sheets are cut to obtain blanks of suitable sizes. All fragments are bent by hand and fixed to each other with epoxy glue. To avoid deformation changes, clamps are mandatory.

The final part is rubbed off from the dried glue. Possible defects are removed from its surface. On last step grinding is carried out.

Some nuances

The above information makes it clear how to bend plywood different ways. For achievement best result It is advisable to familiarize yourself with some of the subtleties:

when soaking, it is allowed to bend the plates only in a state of elevated temperature, otherwise cracks may appear;
elements that will be given a curvilinear shape should be stored in rooms with a stable level of humidity;
with the high cost of the purchased material, you can use the services of specialized companies.

Before bending plywood 10 mm or more, you need to decide on the method used. The option must be selected depending on the angle of the break. As for products of smaller thickness, they are bent only by soaking with water or steam.

Humidification time calculation table

To determine the number of minutes required to soak the material at temperature regime 95 degrees along the fibers, you can use the data presented.

Number of layers	Thickness in mm	Time, min.

Benefits of using bent plywood

These methods allow you to give wood-based panels a smooth shape. Arches, furniture and other decorative elements in this case are aesthetically attractive and mechanically resistant. Curved surfaces make it possible to:

make the number of corners minimal, so that the risk of injury is significantly reduced;
to give the interior sophistication, because the eyes are more interested in smooth transitions;
reduce the number of fasteners.

Plywood sheets are indeed an excellent material for holding finishing works and furniture production. The ability to create curves opens up interesting design possibilities. When using bent forms, you get stylish products and designs.

About the choice of method

Knowing how to bend plywood in three main ways, each craftsman must decide on one of them. Each of the options is not universal, it is relevant in a given situation.

Even the soaking process is not suitable for all cases. With it, you can not make too strong bends, besides, it takes a lot of time, especially if the thickness of the material is high enough.

Not a universal method of creating notches for sheet compliance. Not suitable for thin plywood. Usually, a bend is made if the thickness of the plate is at least 2 cm. As for the gluing technology, it can be considered more universal of all those listed. However, it is applied to thin sheets doesn't make sense. It is easier to bend them immediately by soaking.

Final part

Some companies are engaged in the manufacture of products directly according to the drawings of the customer, so if you wish, you can contact them to avoid unnecessary problems. They produce high quality with various bending radii.

All photos from the article

In this article we will talk about how to bend plywood at home. That is, the listed methods can be applied without the use of specialized equipment and preparations that change the structure of wood.

But, before bending plywood at home, let's decide what this material is and what its structure is.

Main characteristics of the material

Plywood is a multi-layered material of a slab type. As a basis for production, veneer sheets are used, which are stacked on top of each other in a cross position and glued together with a composition containing resins and formaldehydes.

Strength finished material provided by the cross-position of the veneer. That is, in one plate, the transverse and longitudinal directions of the fibers alternate, which means that additional resistance to mechanical stress is acquired.

This is a significant advantage, but if you have to bend plywood with your own hands, high strength turns into a disadvantage. Let's find out how to bend plywood at home and get the desired result.

Steaming and soaking plywood

Steaming plywood is perhaps the most common way to deform glued sawn timber. The advantage of the method is that it is equally relevant in both industrial and domestic conditions.

The bending instruction is nothing complicated, provided that you are going to deform the material no thicker than 4 mm.

From the tool we need the following: