INSTRUCTIONS AND PROPHECIES OF THE Blessed MOTHER ALIPIA GOLOSEEVSKY, Kyiv...
If there is a need to make a curved wooden element, then at first glance it may seem that it is easier to cut 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 out, a large waste of material is obtained, which cannot be said about the method when a wooden blank is simply bent.
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 a 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 a dry tree can break, which is very undesirable.
Having studied the technology, how to bend a tree, as well as the basic physical properties wood, which allow you to change its shape and subsequently save it, it is quite possible to do wood bending at home.
Some features of working with wood
The bending of wood is accompanied by its deformation, as well as compression of the inner layers and stretching of the outer ones. It happens that tensile forces lead to rupture of the outer fibers. This can be prevented by preliminary hydrothermal treatment.
So, you can bend the blanks of a bar made of solid wood and glued wood. In addition, planed and peeled veneer is used for bending. Hardwoods are the most plastic. Among them are beech, ash, birch, hornbeam, maple, oak, poplar, linden and alder. Bent glued blanks are best made from birch veneer. It should be noted that birch veneer occupies approximately 60% of the total volume of bent-glued blanks.
When steaming the workpiece, the compressibility increases significantly, namely by a third, while the tensile ability increases by only a few percent. And, therefore, it is not worth a priori to think about whether it is possible to bend a tree thicker than 2 cm.
Heating in a steam box
First you need to prepare a steam box. It can be handmade. Its main task is to hold the tree that needs to be bent. It must have a hole designed to release steam pressure. Otherwise, it will explode.
The steam outlet should be at the bottom of the box. In addition, a removable lid should be provided in the box through which the bent tree can be pulled out after it has acquired the desired shape. Clamps should be used to hold the bent piece of wood in the desired shape. They can be made independently from wood or bought in a specialized store.
Round trimmings should be made from wood - a few pieces. Holes are drilled in them off-center. After that, 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, for this you should take care of the heat source and close the wood blank in the steam box. For every 2.5 cm of the thickness of the workpiece, it takes about an hour to steam the product. After the time has elapsed, the tree must be removed from the box and given to it. necessary form. The process must be very fast. The workpiece is bent neatly and gently.
Some types of wood bend more easily than others due to different elasticity. different ways require the application of a different amount of force.
Once the desired result is achieved, the bent tree must be fixed in that position. You can pin the tree as it is being formed. This makes it easier to control the process.
With chemical impregnation
To destroy the bonds of lignin between the fibers, you can act on the tree chemicals, and it is quite possible to implement this at home. Ammonia is ideal for this. The workpiece is soaked in a 25% aqueous solution of ammonia. After that, it becomes very obedient and elastic, which allows you to bend, twist it and squeeze relief forms into it under pressure.
Ammonia is dangerous! Therefore, when working with it, all safety regulations must be observed. Soaking the workpiece should be carried out in a tightly closed container located in a room that is well ventilated.
The longer the wood is in the ammonia solution, the more plastic it becomes. After soaking the workpiece and shaping it, you need to leave it in such a curved form. This is necessary to fix the shape, and, well, in order for the ammonia to evaporate. Again, bent wood should be left in a ventilated area. Interestingly, after the evaporation of ammonia, the wood fibers will regain their former strength, and this will allow the workpiece to hold its shape!
Lamination method
First you need to make a blank of wood, which will be bent. The boards should be slightly longer than the length finished part. This is because the bend will shorten the lamellae. Before you start cutting, you should draw a diagonal line with a pencil. You need to do this across the bottom side of the board. This will keep the sequence of slats after they are moved.
The boards are cut with a straight edge, in no case the front side. So, they can be added together with the least change. A cork layer is applied to the mold. This will help avoid irregularities in the shape of the saw, which will allow you to make a sharper bend. In addition, the cork will hold the delamination in shape. Now glue is applied to the top side of one of the wooden lamellas.
Glue is applied to the lamellas with a roller. It is best to use a 2-part urea-formaldehyde adhesive. He possesses high level adhesion, but takes a long time to dry. You can also use 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 in this situation is not welcome at all.
The bent wood blank should be placed in the mold as soon as possible. So, another one is laid on a lamella smeared with glue. The process is repeated until the bent workpiece acquires desired thickness. The boards are fastened together. After the glue is completely dry, shorten it to the desired length.
Drank like a method
The prepared wooden piece must be sawn through. Cuts are made at 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 distance between the kerfs as even as possible. Ideally 1.25 cm.
The cuts are made across the pattern of the wood. Next, you should squeeze the edges of the workpiece so as to connect the resulting gaps together. This shape will acquire a bend at the end of the work. Then the bend is corrected. Most often, the outer side is treated with veneer, in some cases with laminate. This action allows you to correct the bend and hide any defects made during the production process. The gaps between the bent tree are hidden in an elementary way - glue and sawdust are mixed for this, and after this mixture the gaps are filled.
Regardless of the bending method, after the tree is taken out of the mold, the bend will relax slightly. In view of this, it needs to be done a little more in order to subsequently compensate for this effect. The sawing method can be used when bending a part of a box or a metal corner.
If it becomes necessary 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 out, a large waste of material is obtained, which cannot be said about the method when a wooden blank is simply bent.
Wood is cellulose fibers bound together by a chemical called lignin. The flexibility of the tree depends on the arrangement of the fibers.
Note! Only well-dried wood will be a 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 a dry tree can break, which is very undesirable.
Having studied the technology of how to bend a tree, as well as the basic physical properties of wood that allow you to change its shape and subsequently save it, it is quite possible to do wood bending at home.
Some features of working with wood
The bending of wood is accompanied by its deformation, as well as compression of the inner layers and stretching of the outer ones. It happens that tensile forces lead to rupture of the outer fibers. This can be prevented by preliminary hydrothermal treatment.
So, you can bend the blanks of a bar made of solid wood and glued wood. In addition, planed and peeled veneer is used for bending. Hardwoods are the most plastic. Among them are beech, ash, birch, hornbeam, maple, oak, poplar, linden and alder. Bent glued blanks are best made from birch veneer. It should be noted that birch veneer occupies approximately 60% of the total volume of bent-glued blanks.
When steaming the workpiece, the compressibility increases significantly, namely by a third, while the tensile ability increases by only a few percent. And, therefore, it is not worth a priori to think about whether it is possible to bend a tree thicker than 2 cm.
Heating in a steam box
First you need to prepare a steam box. It can be handmade. Its main task is to hold the tree that needs to be bent. It must have a hole designed to release steam pressure. Otherwise, it will explode.
The steam outlet should be at the bottom of the box. In addition, a removable lid should be provided in the box through which the bent tree can be pulled out after it has acquired the desired shape. Clamps should be used to hold the bent piece of wood in the desired shape. They can be made independently from wood or bought in a specialized store.
Round trimmings should be made from wood - a few pieces. Holes are drilled in them off-center. After that, 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, for this you should take care of the heat source and close the wood blank in the steam box. For every 2.5 cm of the thickness of the workpiece, it takes about an hour to steam the product. After the time has passed, the tree must be removed from the box and given the necessary shape. The process must be very fast. The workpiece is bent neatly and gently.
Note! Some types of wood bend more easily than others due to different elasticity. Different methods require the application of a force of different magnitudes.
Once the desired result is achieved, the bent tree must be fixed in that position. You can pin the tree as it is being formed. This makes it easier to control the process.
With chemical impregnation
To destroy the bonds of lignin between the fibers, you can act on the tree with chemicals, and this is quite realistic to do at home. Ammonia is ideal for this. The workpiece is soaked in a 25% aqueous solution of ammonia. After that, it becomes very obedient and elastic, which allows you to bend, twist it and squeeze relief forms into it under pressure.
Note! Ammonia is dangerous! Therefore, when working with it, all safety regulations must be observed. Soaking the workpiece should be carried out in a tightly closed container located in a room that is well ventilated.
Water solution ammoniaAqueous ammonia solution
The longer the wood is in the ammonia solution, the more plastic it becomes. After soaking the workpiece and shaping it, you need to leave it in such a curved form. This is necessary to fix the shape, and, well, in order for the ammonia to evaporate. Again, bent wood should be left in a ventilated area. Interestingly, after the evaporation of ammonia, the wood fibers will regain their former strength, and this will allow the workpiece to hold its shape!
First you need to make a blank of wood, which will be bent. The boards should be slightly longer than the length of the finished piece. This is because the bend will shorten the lamellae. Before you start cutting, you should draw a diagonal line with a pencil. You need to do this across the bottom side of the board. This will keep the sequence of slats after they are moved.
The boards are cut with a straight edge, in no case the front side. So, they can be added together with the least change. A cork layer is applied to the mold. This will help avoid irregularities in the shape of the saw, which will allow you to make a sharper bend. In addition, the cork will hold the delamination in shape. Now glue is applied to the top side of one of the wooden lamellas.
Glue is applied to the lamellas with a roller. It is best to use a 2-part urea-formaldehyde adhesive. It has a high level of adhesion, but takes a long time to dry. You can also use 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 in this situation is not welcome at all.
Boards are bonded after gluing Boards are bonded after gluing
The bent wood blank should be placed in the mold as soon as possible. So, another one is laid on a lamella smeared with glue. The process is repeated until the bent blank acquires the desired thickness. The boards are fastened together. After the glue is completely dry, shorten it to the desired length.
Drank like a method
The prepared wooden piece must be sawn through. Cuts are made at 2/3 of the thickness of the workpiece. They should be on the inside of the bend. You should be extremely careful, because rough cuts can break the tree.
Note! The key to success when cutting kerfs is to keep the distance between the kerfs as even as possible. Ideally 1.25 cm.
Defects can be hidden with veneer Defects can be hidden with veneer
The cuts are made across the pattern of the wood. Next, you should squeeze the edges of the workpiece so as to connect the resulting gaps together. This shape will acquire a bend at the end of the work. Then the bend is corrected. Most often, the outer side is treated with veneer, in some cases with laminate. This action allows you to correct the bend and hide any defects made during the production process. The gaps between the bent tree are hidden in an elementary way - glue and sawdust are mixed for this, and after this mixture the gaps are filled.
Cuts are made across the wood pattern Cuts are made across the wood pattern
Regardless of the bending method, after the tree is taken out of the mold, the bend will relax slightly. In view of this, it needs to be done a little more in order to subsequently compensate for this effect. The sawing method can be used when bending a part of a box or a metal corner.
So, using these simple recommendations you can bend a tree with your own hands without much effort.
Despite all their strength and strength, wooden details can be easily and simply bent, if suddenly during the construction process some special and original part of an oval or round shape. A tree, with proper processing, can easily change its shape, and you can carry out this procedure with your own on their own without resorting to the help of professionals.
Types of work
There are two main ways to bend a tree to the desired shape, and one of them is cold, the other is hot. As the name implies, the methods differ only in the use of hot temperatures, in terms of efficiency, both of these methods are exactly the same, just hot way fixing the tree is much faster. For each method, you will need glue, pva or wallpaper, depending on what is at hand, you do not need to buy anything special. And with the help of metal parts, you can create a kind of press or frame that will hold the tree in the desired shape. In order to bend the beam, it is necessary to lubricate it with glue, strongly and carefully, without fear that the tree will become wet from this. In fact, under the influence of the adhesive solution, all excess moisture will leave the wood, and it will become even more durable and strong, 
which is extremely important. After the beam has been smeared with glue, it must be fixed with tools in the desired shape, and in the case of a cold work process, simply leave it fixed to dry. If you choose hot, then the timber should be covered with a regular film so that it dries faster and all moisture evaporates.
Durability
Whichever method is chosen, both are effective and work in the same way. The beam is completely fixed in its new form, and will no longer return to the old one. You can bend the wet beam from the glue as much as possible, without fear that it will break. And as a result, you will get an original and beautiful piece of furniture or a detail to create an even more attractive interior of the house or its facade. A beam bent with glue will not even need to be processed for durability, which is extremely convenient. Moisture will not soak through the adhesive solution, and insects will not encroach on such a tree in which there will be much more glue. That is why this method is the most optimal and practical, if you urgently need to bend a wooden beam.
It is difficult to make curved furniture frame designs, and the steep curves cut from straight sections of wood will require sophisticated manufacturing techniques to avoid short fiber weakness and large, uneconomical waste. However, complex curved shapes can be produced quite economically using dry or wet bending techniques, and since the fibers run along the bend rather than across it, the finished product will be stronger. Dry bending involves first dividing the wood into thin sections, but thicker parts can be bent by soaking or steaming.
Michael Toneti's curved café chairs and rocking chairs are classic examples of steam-curved furniture, and in the 1930s, glued laminated furniture became a high-fashion item with the invention of industrial methods for producing different grades of plywood. Both steam bending and layer bending can be done in the home workshop, and both methods continue to be used in the antique furniture industry and by skilled craftsmen.
steamed wood can bend with a relatively large bending steepness. The steam softens the wood fibers enough to bend them and mold them to the desired shape. It may take a lot of effort to bend, but this is quite achievable in a home workshop with basic equipment. You will need to make a template, a clamping collar and a steam chamber. Wood bending cannot be attributed to precise procedures. There are many options, and often trial and error is the only way. possible ways obtaining the required result.
Thin wooden blanks do not require prior preparation. The minimum radius to which it can be bent will depend on the thickness and natural properties of the wood species. Thin wood, in the absence of deformation limiters (and in the form, for example, of a template), will take the form of a ring when freely bent, if the ends of the workpiece are brought together. To obtain a greater bending steepness, the wood must be steamed and “hold” fixed on the template so that it, having taken the desired shape, stabilizes in this position due to internal residual deformation. When thick wood is bent, it is necessary to limit the stretching of the outer layers to prevent them from chipping or breaking. The method described here is for bending relatively thick pieces of wood.
Wood preparation
For bending, choose straight-grained wood without knots and cracks. Any defect or shortcoming is potentially a weak point, so certain failures are possible. There are dozens of woods that are successfully steam-bent, and many of them are hardwoods. In the table below you can find a short list of suitable materials for bending. It is possible to bend well-dried wood, but freshly cut wood lends itself to such processing more easily. Atmospheric wood bends better than kiln- or kiln-dried wood. If the wood is too dry and difficult to process, you can soak it for several hours before steaming.
Depending on the type of workpiece, you can pre-cut it to size or do it with a saw, plow or scraper after bending. The latter method is often used in the production of bent furniture such as Windsor chairs and armchairs. Wood with a flat and smooth surface finish is less prone to delamination and will final finishing the whole product is lighter. Raw wood shrinks more than seasoned wood, and when processed for lathe before bending, it tends to take an oval shape in cross section when dried. Regardless of the shape and size, make the length of the workpiece longer than the length finished product approximately 100 mm. Then, in case of delamination or splitting of the ends after bending, it will be possible to cut off the damaged areas.
To calculate the length, make a drawing of the shape of the bend on a scale of 1: 1. Measure the outside of the curved part to get the correct length. This will allow you not to unnecessarily stretch the outer fibers, which could lead to cracking under the influence of internal stresses. The softened inner fibers will be able to shrink enough to take the form of a smaller inward bend.
The key to making a tight bend is the use of a flexible clamping collar. Make a mild steel collar 2 mm thick and at least as wide as the workpiece that is not already bent. This will work for just about any job you might need to do. To avoid possible contamination of the surface of the part as a result of interaction reactions chemical elements wood, metal and environment, clamp make of of stainless steel or galvanized steel, or use a polyethylene gasket.
Install end stops or stops on the clamp to fix the ends of the workpiece, thereby preventing the fibers on the outside of the bent part from stretching and stratifying. These stops must be strong enough to withstand significant pressure on them, and be of sufficient size so that the end of the workpiece can abut against the stop with its entire surface. You can make them from a thick metal corner or from hard wood, which is usually easier to do.
To equip the clamp with reliable end stops, install on the ends of the metal tape wooden blocks approximately 225 mm long. On the center lines of each block, drill two holes with a diameter of 9 mm at a distance of about 150 mm from each other. Mark and drill the clamp strip for the end stop mounting bolts. The distance between the stops must be equal to the length of the workpiece, including the allowance. In order for the clamp to have a convenient lever action for work, attach sufficiently strong wooden blocks to the ends of the strip on the back side of it using long stop bolts.
Template making
The steamed wood bends in a pattern that defines the shape of the curve and provides support for the fibers of the interior of the curved piece. The template must be of great strength and have a width at least equal to the width of the part to be bent. It must provide certain possibilities for fixing the workpiece on it with the help of clamps or other clamps.
You can make a template out of thick wood by setting the mold out of it on a base made of artificial wood materials, or use sheets of plywood glued together. Because the bent wood tends to straighten out after the clamp is released, it is necessary to correct the shape of the template taking into account the straightening of the part. To do this, you will have to use the most reliable, although not always pleasant way - the trial and error method to determine the parameters of such a correction.
Types of wood for steam bending
- Ash
Fraxinus excelsior
Fraxinus amcricana - Beech
Fagus grandifolia
Fagus sylvatica - Birch
Betula pendula
Benda alleghaniensis - Elm
Ulmus americana
Ulmus procera
Ulmus liollandica
Ulmus thomasii - Hickory Cartja spp.
- Oak
Quercus rubra
Quercus petraea - Nut
Juglans nigra
Juglans regia - Yew
taxus baccara
Making a steam chamber
Make a steam chamber out of plywood for outdoor use, or use plastic or metal tubing. Plywood allows you to craft with glue and screws simple design exactly according to your specific requirements. This type of chamber is ideal if whole batches of wood are to be steamed. Camera made of plastic or metal pipe limits the size range, but is quite suitable for small workpieces.
Cut a piece of pipe of the required length in accordance with the dimensions of the workpiece. A length of 1 m is a convenient size that allows you to process entire workpieces or even parts of increased length, if you only need to bend its end part. Make removable plug-in end dampers out of plywood for outdoor use. Drill a hole in one of them for a steam pipe and with a planer cut off the lower part of the edge of the other damper to create a ventilation and drainage hole. Make special "open" shutters with a hole for long workpieces. Set inside corpses wooden poles so that the workpiece does not touch the bottom of the chamber. Insulate the chamber with styrofoam or wooden blocks, securing them to the chamber with wire. Install the camera on stands with a slight slope so that condensation can flow out. Provide a reservoir for escaping water.
Steam can be generated using a small electric vaporizer or a factory-made steam generator, or you can make your own vaporizer from a 20-25L metal tank with a removable cap or stopper. Connect one end of a short rubber hose to a branch pipe or valve (valve) soldered into the tank, and insert the other into the hole in the chamber damper. To heat water, you can use any heating device, such as an electric or gas stove. Fill the tank halfway with water and heat it up to 100°C. to ensure a constant supply of steam. Approximately the wood should be steamed for 1 hour for every 25 mm of thickness. Longer steaming will not necessarily improve the plasticity of the wood, but it can destroy its internal structure.
wood bending
You will only have a few minutes to fix the workpiece in the template before it starts to cool and stabilize. Prepare in advance workplace. Have a sufficient number of clamps available and, in the case of processing very thick wood, arrange with a friend for help.
Shut off the steam supply and turn off the steam generator. Remove the workpiece from the chamber and place it in a pre-fitted and heated collar. Install it all together on a template. Fix the center by placing a piece of wood between the clamp and the collar. With an interference fit, “wind” the workpiece onto the template and clamp it securely in place with several clamps. Allow the part to stabilize for at least 15 minutes before transferring it to an identically shaped drying mandrel or template. You can leave the blank on the first template. In any case, keeping the material should take from 1 to 7 days.
Security measures
When bending with steaming, observe the following rules:
- Do not overtighten the lid or plug of the steam generator.
- Ensure that the steam chamber is well ventilated.
- Do not let the steam generator run without water.
- Do not stand or lean over the steam generator and steam chamber when opening them.
- Wear thick gloves or mittens when handling heated workpiece and steaming equipment.
- The source of steam must be removed at a considerable distance from flammable objects to materials.
