Instructions
For the manufacture of curved parts from wood, two main methods are used: sawing according to a template and bending pre-steamed wood using a template on special machine. The first method leads to cutting the fibers and reducing the strength of the parts. Bending provides a high percentage useful output details and significant strength. Bent parts can be finished with high quality and subject to various machining(profile, form spikes, eyes, etc.).
Ability wooden board bendability is determined by the plasticity of the wood and depends on the type of wood. Beech, birch, oak, pine and spruce have the greatest plasticity. But you can control the plastic properties of the workpiece by hydrolyzing it heat treatment.
At a temperature of 100°C and a humidity of 30%, part of the substances that make up the cells of the material goes into a gel state, while the cell walls and wood fibers become elastic and soft. This wood bends easily. After drying bent board retains its given shape as colloidal substances harden.
Processing the workpiece consists of boiling it in hot water or steaming with saturated low pressure steam. Steaming is more common, since with this treatment the wood is heated more evenly and the wood does not become excessively moistened.
When a board treated in this way is bent on a pattern or in a special clamping device, internal stresses arise in the material. Wood stretches on the convex side and contracts on the concave side. In the middle neutral layer the voltages are zero.
The outer layer will become elongated under tensile stresses, and the inner layer will become shorter. The amount of deformation depends on the thickness of the dock and the bending radius. To limit the elongation of wood fibers and prevent their possible rupture, a special steel bus with a thickness of up to 2.5 mm is applied to the convex side of the bent part. The workpiece is bent together with the tire. In this case, the neutral line extends towards the stretched fibers beyond the board, and bending occurs only due to compression.
When making a wide variety of carpentry products, the craftsman often has to use curved parts. It is not always possible to obtain the required shape by sawing, since ensuring the strength of the material and its economy are important here. In such cases, it is necessary to bend the wood at different angles.
You will need
- - hot water;
- - open fire;
- - sample;
- - steel strip;
- - ammonia water.
Instructions
Use steaming or heat treatment for bending. If you expose the wood for several hours to high temperature and moisture, you can achieve a change in the plasticity of the material and bend the workpiece at the required angle.
Carefully select the ones you will subsequently bend. Use boards sawn lengthwise for this treatment. Avoid defective and twisted boards, as well as those workpieces that have knots. If you use materials with damaged fibers, the workpiece may crack at the location of the defect.
If there is a need to manufacture a curved wooden element, then at first glance it may seem that it is easier to cut out the desired element in a curved form, but in this case, the fibers of the wood material will be cut, thus weakening the strength of the part, and as a result, the entire product. In addition, when sawing, a large waste of material is obtained, which cannot be said about the method when wooden blank they simply bend.
Wood is cellulose fibers bound together by a chemical called lignin. The flexibility of the tree depends on the arrangement of the fibers.
Only well-dried wood will be reliable and durable source material for the production of various products. However, changing the shape of a dry wooden blank is a complex process, because dry wood may break, which is very undesirable.
Having studied the technology of how to bend wood, as well as the basic physical properties wood, which allow you to change its shape and subsequently preserve it, it is quite possible to take up bending wood at home.
Some features of working with wood
Bending of wood is accompanied by its deformation, as well as compression inner layers and stretching of the external ones. It happens that tensile forces lead to rupture of the outer fibers. This can be prevented by carrying out preliminary hydrothermal treatment.
So, you can bend blanks of timber made from solid and laminated wood. In addition, planed and peeled veneer is used for bending. The most plastic are hardwoods. These include beech, ash, birch, hornbeam, maple, oak, poplar, linden and alder. Bent glued blanks are best made from birch veneer. It is worth noting that in the total volume of bent-glued blanks, birch veneer occupies approximately 60%.
When steaming the workpiece, the compressibility increases significantly, namely by a third, while the tensile ability increases by only a few percent. This means that it is not a priori worth thinking about whether it is possible to bend wood thicker than 2 cm.
Steam box heating
First you need to prepare the steam box. It can be made by yourself. Its main task is to hold the tree that needs to be bent. There should be a hole in it to allow the steam pressure to escape. Otherwise it will explode.
The steam outlet should be located in the bottom of the box. In addition, the box should have a removable lid through which you can pull out the bent wood after it has acquired the required form. To hold the wooden bent part in the desired shape, clamps should be used. You can make them yourself from wood or buy them at a specialty store.
Should be made from wood round trimmings- some. Off-center holes are drilled in them. After this, you need to push the bolts through them, and then drill another hole through the sides to push them in tightly. Such simple crafts can become excellent clips.
Now it’s time to steam the wood; to do this, you should take care of the heat source and close the wood piece in the steam box. For every 2.5 cm of thickness of the workpiece, the product needs to be steamed for about an hour. After time has passed, the tree must be removed from the box and given the required shape. The process must be completed very quickly. The workpiece bends neatly and softly.
Some types of wood bend more easily than others due to different elasticity. Different ways require the application of force of varying magnitude.
Once the desired result is achieved, the bent tree must be fixed in this position. You can secure the tree while shaping it. This makes it easier to control the process.
Using chemical impregnation
To destroy lignin bonds between fibers, you can act on wood chemicals, and it is quite possible to do this at home. Ammonia is ideal for this. The workpiece is soaked in a 25% aqueous ammonia solution. After which it becomes very obedient and elastic, which allows you to bend, twist it and squeeze out relief shapes in it under pressure.
Ammonia is dangerous! Therefore, when working with it, you should follow all safety rules. Soaking the workpiece should be carried out in a tightly closed container located in a well-ventilated room.
How longer wood is in an ammonia solution, the more plastic it becomes. After soaking the workpiece and giving it a shape, you need to leave it in this curved form. This is necessary to fix the shape, and also for the ammonia to evaporate. Again, bent wood should be left in a ventilated area. Interestingly, after the ammonia evaporates, the wood fibers will regain their former strength, and this will allow the workpiece to retain its shape!
Delamination method
First you need to make a piece of wood that will be bent. The boards should be slightly longer than the length finished part. This is because bending will shorten the slats. Before you start cutting, you should draw a diagonal line with a pencil. This needs to be done across bottom side boards. This will maintain the sequence of the slats after they have been moved.
The boards are cut with a straight-layer edge, in no case front side. So, they can be added together with the least change. A layer of cork is applied to the mold. This will help avoid any unevenness in the shape of the saw, allowing for a cleaner bend. In addition, the cork will keep the delamination in shape. Now glue is applied to the top side of one of the wooden slats.
The glue is applied to the lamellas with a roller. It is best to use urea-formaldehyde glue, consisting of 2 parts. It has a high level of adhesion but takes a long time to dry. Can also be used epoxy resin, but such a composition is very expensive, and not everyone can afford it. Standard wood glue cannot be used in this case. It dries quickly, but is very soft, which is not welcome in this situation.
Blank from bent wood should be placed in the mold as quickly as possible. So, another lamella is placed on top of the lamella coated with glue. The process is repeated until the bent workpiece acquires required thickness. The boards are fastened together. After the glue has completely dried, you should shorten it to the desired length.
I drank it as a method
The prepared piece of wood needs to be sawn through. The cuts are made 2/3 of the thickness of the workpiece. They must be with inside bending You should be extremely careful, because rough cuts can break the tree.
The key to success when cutting kerfs is to keep the spacing between cuts as even as possible. Ideally 1.25 cm.
The cuts are made across the grain of the wood. Next, you should squeeze the edges of the workpiece so as to connect the resulting gaps together. This is the shape the bend will take upon completion of the work. Then the bend is corrected. Most often, the outer side is treated with veneer, or in some cases with laminate. This action allows you to correct the bend and hide any defects made during the manufacturing process. The gaps between the bent wood are hidden simply by mixing glue and sawdust, and then filling the gaps with this mixture.
Regardless of the bending method, once the wood is removed from the mold, the bend will relax slightly. In view of this, it needs to be made a little more in order to subsequently compensate for this effect. The sawing method can be used when bending part of the box or metal corner.
If there is a need to develop a curved element made of wood, then most likely you will encounter a number of difficulties. At first glance, it will seem that it will be easier to cut out the required element in a curved form, but in this option, the wood fibers will be cut and weaken the reliability of the part. Plus, during execution there is a very large consumption of material.
Stages of work on bending boards at home:
Wood is cellulose fibers bound together by lignin. Placing the fibers in a straight line affects the flexibility of the wood material.
Tip: durable and reliable material Wood can be used to make all kinds of products only if the wood is perfectly dried. However, a change in the form of dry wood harvesting is sufficient labor-intensive process, since dry wood can break easily.
Having studied the technology of bending wood, including its basic physical properties of wood, which allow changing its shape, it is quite possible to bend wood material in artisanal conditions .
Specifics of working with wood
Bending of wood material is accompanied by its deformation, stretching of the outer layers and compression of the inner ones. It happens that the tensile force leads to rupture of the outer fibers. This can be prevented by carrying out preliminary hydrothermal finishing.
Can bend timber blanks made from laminated and solid wood. Plus, to give the desired shape, peeled and planed veneer is used. It is considered the most plastic hardwood. Which includes beech, birch, hornbeam, ash, maple, oak, linden, poplar and alder. Glued bent blanks are best made from birch veneer. It should be noted that in the total volume of such blanks, about 60% falls on birch veneer.
By production technology bent wood, when the workpiece is steamed, its ability to compress significantly increases, specifically by a third, while the ability to stretch increases by only a few percent. Thanks to this, you can’t even think about bend tree thicker than 2 cm.
How bend board in artisanal conditions: heating in steam box
First of all, you need to prepare a steam box, which can be made with my own hands. Its main task is to restrain the tree, which is required bend. There must be a hole in it that is designed for steam to escape. Otherwise, an explosion may occur under pressure.
This hole should be located in the bottom of the box. Plus, in the box you need to calculate a removable lid through which you can remove bent wood, as soon as it receives the required form. In order to hold the bent wood blank in the required shape, it is necessary to use special clamps. They can be done without outside help made of wood or purchased at a building materials store.
Several round scraps are made from wood. Holes are drilled in them, offset from the center. After this, you need to push the bolts through them, and then drill another through the sides to push them in firmly. Such simple crafts can perfectly serve as clamps.
Now you can start steaming the wood. To do this, you need to close the wood blank in a steam box and worry about the heat source. For every 2.5 cm of product thickness, the time spent on steaming will be approximately an hour. After its expiration, the tree should be removed from the box and given the required shape by bending it. The process should be performed quickly enough, and the bending itself should be done gently and carefully.
Tip: due to varying degrees of flexibility, some types of wood will bend more easily than others. Any method requires the application of varying amounts of force.
As soon as the result you want is achieved, the bent workpiece must be secured in this position. Fastening a tree is possible during the process of its development new form, making it easier to control the process.
How bend board in artisanal conditions using chemical impregnation
Since lignin is responsible for the stability of wood, its bonds with the fibers must be broken. This is achieved chemically, and it is quite possible to do this in artisanal conditions. Best suited for such purposes ammonia. The workpiece is soaked in a 25% aqueous solution of ammonia, which significantly increases its plasticity. Likewise, it will be possible bend, twist it or squeeze out some relief shapes under pressure.
Advice: you should look at the fact that ammonia is dangerous! Due to this, while working with it, it is necessary to strictly adhere to all safety regulations. Soaking of wood must be carried out in a tightly closed container, which is located in a well-ventilated area.
The longer the wood is soaked in an ammonia solution, the more plastic it will become later. After soaking the workpiece and developing its new shape, it is necessary to leave it in a similar curved form. This is necessary not only to fix the shape, but also to evaporate the ammonia. However, bent wood must be left in a ventilated area. It is noteworthy that when the ammonia has evaporated, the wood fibers will acquire the same reliability as before, which will enable the workpiece to retain its own shape!
How bend board in artisanal conditions: layering method
First you need to harvest wood, which will subsequently be prone to bending. It is very, very important that the boards are slightly longer than the length required part. This can be explained by the fact that the bending tames the lamellas. Before you start cutting, you will need to draw a straight line diagonally with a pencil. This must be done across the underside of the workpiece, which will make it possible to preserve their order after moving the lamellas.
The boards must be cut with a straight-layered edge, and not with the right side at all. Likewise, they can be put together with the least amount of change. A layer of cork is applied to the mold, which can help avoid any unevenness in the shape of the saw and will provide the opportunity to make a more even bend. Plus, the cork will prevent delamination in the mold. After that, glue is applied to the upper side of one of the lamellas with a roller.
It is best to use urea-formaldehyde glue, consisting of two parts. It has a high level of adhesion, but takes a long time to dry. You can also apply resin to epoxy based, but such a composition will cost a lot of money, and absolutely not everyone can afford it. The standard version of wood glue is not suitable for this type of application. Although it will dry quickly, it is considered too soft, which is not at all welcome in this option.
A bentwood product must be placed into the mold as quickly as possible. So, another one is placed on the lamella coated with glue. The process must be repeated until the bent workpiece receives required thickness. The boards are fixed together. After the glue has completely dried, it is necessary to shorten it to the required length.
How bend board in artisanal conditions: cut through
The prepared piece of wood needs to be sawn through. The cuts are calculated at 2/3 of the thickness of the workpiece. They must be located inside the bend. You need to be very careful, as rough cuts can easily deform the tree and even completely break it.
Tip: The key to cutting success is to keep the distance between cuts as even as possible. The best option 1.25 cm.
The cuts are made across the grain of the wood. Afterwards you need to compress the edges of the workpiece, which will make it possible to combine the resulting cracks into a single whole. This is the shape the bend takes upon completion of the work. After which he is corrected. In many cases, the outer side is finished with veneer, less often with laminate. This impact will give you the opportunity to correct the bend and hide almost any defects made during manufacturing. Gaps in bent tree they are hidden quite easily - for this, sawdust and glue are mixed, after which the gaps are filled with the mixture.
Regardless of the bend option, as soon as the workpiece is removed from the mold, the bend will relax a little. In view of this, it must be made a little larger in order to compensate for this effect later. The sawing method is used when bending a metal corner or part of a box.
So, using such tips you can big problems bend wood with your own hands.
How to bend a board, plywood, fiberboard, MDF with your own hands
Often during the process repair work There is a need to obtain curved surfaces of products made from wood. How to bend a board so that the bend is strong and does not crack during the bending process? Well, if you have already decided to do major renovation with your own hands, then you should not retreat in the face of such difficulties. In this article we will talk in detail about how to give wood material a curved shape.
How to bend a tree?
No, our task is not at all to bend an innocent plant. We are talking about wood building materials. How to bend a tree so that it bends and does not break? Bending method wooden products known since ancient times: to give wood a shape, only heat and moisture are needed, under the influence of which the plasticity of the material increases with all the ensuing consequences. How to bend a tree? Keep it in hot water ( the higher the temperature, the faster the processes occur) or steam ( a steam generator can be made from a kettle or use an iron). The higher the temperature, the faster the wood gives way and you can start bending it. Moistened and heated wood can be bent under the influence of a load (the ends of the board are placed on supports), and a load is placed in the place of the future bend. Dried wood perfectly retains the minimum radius of curvature that was achieved during the bending process. Now we know how to bend wood, we can dwell on this issue in more detail.
Wood reaction to external influences
The fact is that wood reacts differently to bending. The convex part is subject to tension, the concave part is subject to compression. Moreover, the material also reacts differently to steaming. For example, the ability to compress increases by as much as a third, but the ability to stretch - just a couple of percent. That’s why you shouldn’t think about how to bend a board more than two centimeters thick at home. It is also necessary to take into account that different types wood reacts differently to bending. For example, such species as oak, larch, and maple bend poorly, but beech, ash, and walnut bend well. So before you think about how to bend the board, decide on the type of wood from which it is made.
How to bend plywood, fiberboard, MDF
At home, plywood is bent by increasing its humidity, then ironing it (an iron is required), and fixing it in a template. Any frame element can serve as a template and its shape does not necessarily have to be curvilinear. The product is attached to the template using tape. Can be clamped bent plywood between two spacers, give it a bent shape using ropes, tying them around the product in several places along the radius of curvature. Plywood can only be used after it has dried. It seems that we have figured out how to bend plywood - let's move on.
How to bend fiberboard? The technique is the same as in the previous case! How to bend MDF? In this case, you can go two ways: either bend thin sheets(no more than 5 mm) and glue them together, or use flexible MDF. in which there are transverse slots on one side. The thickness of such sheets is usually 8 mm. When bending, they are placed on top of each other with their milled sides, and then glued together. That's all!
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If there is a need to create a curved wooden element, then most likely you will encounter a number of difficulties. It may seem easier to cut the required component in a curved form, but in this case the wood fibers will be cut and weaken the strength of the part. In addition, the execution results in a fairly large waste of material.
Stages of performing work on bending boards at home:
| Preparation. Choice suitable variety trees and familiarization with general principles work with him. | |
 |
Wood bending options. Heating in a steam box, chemical impregnation, delamination, cutting. |
Wood is cellulose fibers bound together by lignin. The straight arrangement of the fibers affects the flexibility of the wood material.
Tip: reliable and durable wood material to create various products can only be achieved if the wood is well dried. However, changing the shape of a dry piece of wood is a rather difficult process, since dry wood can easily break.
Having studied the technology of bending wood, including its main physical properties of wood, which allow you to change its shape, it is quite possible to perform bending wooden material at home.
Features of working with wood
Bending of a wooden material is accompanied by its deformation, stretching of the outer layers and compression of the inner ones. It happens that the tensile force leads to rupture of the outer fibers. This can be prevented by pre-hydrothermal treatment.
You can bend blanks of timber made of laminated wood and solid wood. In addition, peeled and sliced veneer is used to give the required shape. The most plastic is hardwood. Which includes beech, birch, hornbeam, ash, maple, oak, linden, poplar and alder. Glued bent blanks are best made from birch veneer. It should be noted that in the total volume of such blanks, about 60% falls on birch veneer.
According to the technology for manufacturing bent wood, when the workpiece is steamed, its ability to compress significantly increases, namely by a third, while the ability to stretch increases by only a few percent. Therefore, you cannot even think about bending wood thicker than 2 cm.
How to bend a board at home: heating in a steam box
First you need to prepare a steam box, which can be done by yourself. Its main task is to hold the tree that needs to be bent. It must have a hole for steam to escape. Otherwise, an explosion may occur under pressure.
This hole should be in the bottom of the box. In addition, the box must have a removable lid through which the bent wood can be removed after it has received the desired shape. In order to hold the bent wood workpiece in the required shape, it is necessary to use special clamps. You can make them yourself from wood or purchase them at a hardware store.
Several round scraps are made from wood. Holes are drilled in them, offset from the center. After that, you should push the bolts through them, and then drill another one through the sides in order to push them in tightly. Such simple crafts can perfectly serve as clamps.
Now you can start steaming the wood. To do this, you need to close the wooden piece in a steam box and take care of the heat source. For every 2.5 cm of product thickness, the time spent on steaming is about an hour. After its expiration, the tree should be removed from the box and given the required shape by bending it. The process should be carried out very quickly, and the bending itself should be gentle and careful.
Tip: due to different degrees of elasticity, some types of wood will bend more easily than others. Different methods require different amounts of force to be applied.
As soon as the desired result is achieved, the bent workpiece must be fixed in this position. Fastening the tree is possible during the process of forming its new shape, due to which it will become much easier to control the process.How to bend a board at home using chemical impregnation
Since lignin is responsible for the durability of wood, its bonds with the fibers must be broken. This can be achieved chemically, and it is quite possible to do this at home. Ammonia is best suited for such purposes. The workpiece is soaked in a 25% aqueous ammonia solution, which significantly increases its elasticity. This will make it possible to bend, twist it, or squeeze out any relief shapes under pressure.
Tip: Please note that ammonia is dangerous! Therefore, when working with it, you must strictly adhere to all safety regulations. Soaking of wood should be carried out in a tightly closed container, which is located in a well-ventilated area.
The longer the wood is soaked in an ammonia solution, the more plastic it will become later. After soaking the workpiece and forming its new shape, you should leave it in a similar curved form. This is necessary not only to fix the shape, but also to evaporate ammonia. However, bent wood should be left in a ventilated area. Interestingly, when the ammonia evaporates, the wood fibers will regain the same strength as before, allowing the workpiece to retain its shape!
How to bend a board at home: layering method
First, it is necessary to harvest wood, which will subsequently be subject to bending. It is extremely important that the boards are slightly longer than the length of the required part. This is explained by the fact that the bending tames the lamellas. Before you start cutting, you will need to draw a diagonal straight line with a pencil. This must be done across the bottom side of the workpiece, which will make it possible to maintain their sequence after moving the lamellas.
The boards need to be cut with a straight-layered edge, and not with the right side. This way they can be put together with the least amount of change. A layer of cork is applied to the mold, which will help avoid any unevenness in the shape of the saw and will make it possible to make a more even bend. In addition, the cork will keep the delamination in shape. After this, glue is applied to the upper side of one of the lamellas with a roller.
It is best to use urea-formaldehyde glue, consisting of two parts. He has high level clutch, but takes a long time to dry.
You can also use epoxy resin, but such a composition will be very expensive, and not everyone can afford it. Standard option Wood glue will not work in this case. Although it dries quickly, it is very soft, which in this case is not welcome.
The bentwood product must be placed into the mold as soon as possible. So, another one is placed on the lamella coated with glue. The process must be repeated until the bent workpiece reaches the desired thickness. The boards are fastened together. After the glue has completely dried, you should shorten it to the required length.
How to bend a board at home: cut
The prepared piece of wood must be sawn through. The cuts are calculated at 2/3 of the thickness of the workpiece. They should be located on the inside of the bend. You need to be extremely careful, as rough cuts can not only deform the tree, but even break it completely.
Tip: The key to success when cutting is to keep the distance between cuts as even as possible. Perfect option 1.25 cm.
The cuts are made across the grain of the wood. Then you need to compress the edges of the workpiece, which will allow you to connect the resulting gaps into one whole. This is the shape it gets bent at the end of the work. After that it is corrected.
In most cases outer side processed with veneer, less often with laminate. This action makes it possible to correct the bend and hide almost any defects made during the manufacturing process. Gaps in bent wood are hidden very simply - for this, sawdust and glue are mixed, after which the gaps are filled with the mixture.
Regardless of the bend option, after the workpiece is removed from the mold, the bend will relax a little. In view of this, it should be made a little larger in order to subsequently compensate for this effect. The sawing method is used when bending a metal corner or part of a box.
So, using these recommendations, you can bend a tree with your own hands without any problems.