Everyone who had to work with wood, whether it was a wooden floor device, carpentry or wood crafts, is well aware of its most unpleasant property. No matter how high-quality the raw wood is, when dried, it will necessarily warp or take deep cracks

This is because a living tree is filled with juices, like a sponge. Under the influence of air temperature, the top layer of the wood dries much faster than the inside. And the higher the air temperature, the greater this difference will be. But how to dry a tree so that it does not come cracks and it was possible to work with it further without fear of warping?

Wood Drying Requirements

Methods of drying wood: a - natural, b - in a low-temperature chamber, c - under high-frequency currents, g - in a condensation chamber.

Drying consists of 2 processes that occur in a tree at the same time. Moisture evaporates from the surface of the tree, and the one that was originally inside the trunk moves from the center to its surface. The larger the workpiece, the longer it takes for the moisture to evaporate. For wood that will be used outdoors, the residual moisture should be between 12-18%. But if it is supposed to use wood or wood products in a heated room, then it will have to be additionally dried at room temperature. The residual moisture in it should not exceed 8-10%.

In industrial conditions, when drying wood, a special device is used to determine its moisture content - an electric moisture meter. But at home, there is no need to purchase such a device for a pair of blanks. The moisture content of wood can quite accurately be determined by touch. To do this, just squeeze a few wooden shavings in your hand. If the tree is dry, then the chips in the hand will break, and if not, they will be compressed.

If you have to deal with wood harvesting, remember: the tree has the least moisture since it completely dropped the leaves, and until the buds begin to swell on it. If you decide to prepare wood for further processing yourself, then it is better to do it precisely during this period.

Let us consider in more detail the different methods of drying wood.

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Vine drying

The most reliable is drying in the vine. It can be carried out from spring to the end of summer. Later, qualitatively drying the tree on the vine will be problematic, since at that time it distills moisture along the trunk less, preparing for hibernation.

On a tree trunk at a distance of 0.3-0.5 m from the ground, a ring of bark is removed. The width of the ring can be taken arbitrarily, but most often it is made from 1 to 1.5 m. If you remove the bark less, the drying time will increase, and remove more - it’s inconvenient for many because of their growth.

This method is good in that it allows you to dry the tree quickly. The removed bark does not allow moisture to enter the crown of the tree, at the same time, the foliage continues to intensively consume the remaining moisture in the trunk, dehydrating it. When the foliage on the tree dries, it can be cut and cut. The wood in it will be dry, and it can safely be used for its intended purpose.

This method is good when you need to quickly dry single trees. But in the forest, you can perform this process in a different way. The tree needs to be cut; from the saw cut, leave a 0.7-1 m ring of bark around the trunk. And then 2/3 of the trunk can be robbed without touching the crown. The remaining foliage will continue to do its work for some time, having dried the trunk of the tree in a week, as in normal conditions it would not have dried in a month.

After 2-3 weeks of such drying, the trunk is cut into pieces you need.

But immediately put them into business is not worth it, the wood must still be dried.

They do this under a canopy, laying 0.25-0.5 m high flooring under the wood to prevent even the slightest contact with the ground.

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Wood drying in atmospheric conditions

The workpiece is boiled in water for several hours. After digestion, it is dried away from sunlight.

For this purpose, an even, dry area is selected on the site. Place should be on a raised platform to avoid flooding. It is built on the flooring of poles, on which billets are stacked.

The top row of the stack, whether it’s round logs or boards, is laid, making a slight bias, and covered to protect it from rain and from the sun. If a roundwood of coniferous wood is used for drying, then it is better not to remove the bark from it, otherwise, even covered, it will crack. To protect the ends of the round timber from decay, they are treated with lime, liquid glue or a solution of sodium chloride.

This method allows you to take away from wood about 75% of the moisture originally in it. However, with its help it is impossible to dry the tree quickly - the average drying speed can be taken as 1 cm per year. But this value depends on numerous factors: the type of wood, the thickness and type of wood, and weather conditions. Therefore, it is better to assume that softwood and softwood dry for 1-1.5 years, and hardwood for 2 years or more.

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Drying wood with newspapers and straw

These methods are used when you need to dry small wooden workpieces. When using newspapers, the wooden blank is wrapped with dry newspapers and then put in a plastic bag. The package is tightly wrapped and put in a warm place - the warmer the better. When the newspaper in the bag becomes wet, the bag is opened, the wet newspaper is removed from the workpiece and changed to dry.

Depending on the initial moisture content of the wood, this process can take 3-4 weeks. Over time, the intervals between newspaper shifts will increase, as moisture in the workpiece will become less. Moreover, to accelerate the drying process, you can increase the thickness of the newspaper layer, but it should be remembered that too rapid loss of moisture will lead to cracks.

Drying wood with dry straw uses the same principle as newspaper drying. Only in this case, wooden billets are not dried in a warm place, but under a canopy, covered with a thick layer of dry straw. Straw, like newspapers, takes moisture from a tree, but, unlike newspapers, there is no need to change it every day, it dries itself. If there is no straw at hand, dry shavings or sawdust can replace it with equal success.

The problem of maintaining optimal humidity in lumber is relevant both among builders and amateurs to make something in their own carpentry workshop. Drying wood at home can save a lot on its purchase, because dry raw materials always cost more than wet ones.

By the way, if you have absolutely no time for construction work, then you can dry the wood at home or in the country even under atmospheric conditions.

Some owners adapt for this purpose the ready-made premises of hayfields, sheds or other suitable buildings. Here is one way out of the situation found by one of our members of the forum.

Timakval member FORUMHOUSE

I used for drying the attic of the yard (the former hayed) the size of 10 * 5 m. I laid out, as it should, through the gaskets each row. Total 3.5 cubic meters of boards of different categories. The advantages of this drying place are always a shade, a finished roof and it is aired well. Last May I took different sizes of boards, bars and timber - a blank for small construction. The boards were unstoppable from moisture. During lying on the hayloft (1.5-2 months), they dried up in the fluff, they were not twisted or bent.

Drying under atmospheric conditions is a rather lengthy process, and since we decided to comprehensively approach this issue, then let's look at the sequence of building a home dryer with our own hands, which allows us to more effectively achieve the required humidity indicators. As a suitable room, we suggest you choose the building of the required size, and after that you can already start work. The room may have dimensions of 2 * 3 m or 4 * 3 m (possibly larger). It all depends on your needs and scope of activities. But, when choosing a building, it should be remembered that there should not be much free space in the dryer. After all, drafts and chaotic air movement adversely affect the quality of wood.

DIY wood dryer

The room chosen to equip a home-made dryer should be heated by a stove or a specially installed fireplace. It is good if the heater will be pre-mounted in the room. If there is none, then do not forget to leave a place for him.

Here's a project for making a home dryer offered by a participant in our forum.

Nikolay Valen FORUMHOUSE member

There is a major garage with water heating, as a boiler a stove is installed on wood and working out. There is a pipe with a diameter of 800 mm and a length of 2.2 meters (a former ventilation duct from an industrial enterprise). The idea is as follows: install sealed caps at both ends of the pipe, leave a fitting with a diameter of 150-200 mm for supplying and discharging hot air. Air heating is carried out by a radiator (it can be a car stove). Air supply - desktop fan. 0.3-0.5 cubic meters of lumber is loaded into the pipe, the furnace is melted (the temperature of the coolant reaches 90 degrees, I think that the supplied air can really be heated to 50-60 degrees).

If you choose a room that is too large, then the space planned to be used for a makeshift dryer should be isolated and sealed. For these purposes, wooden partitions are made, you can use insulation, brick and other materials to create your own microclimate in the dryer. Do not forget that the ventilation window and the front door must be left in the chamber. After all, we should not get a hut without windows and doors.

Fans installed in the room of the drying chamber will help to create a forced air flow and make the drying process more efficient.

mfcn member FORUMHOUSE,
  Moscow.

It is advisable to place the fans on the floor on the side of the stack so that it blows parallel to the gaskets. Remember that when drying wood, you need to evaporate about several hundred liters of water from each cubic meter of wood.

To place lumber in the dryer, special shelves or floorings should be installed. These products can be made metal - so that the structure can withstand relatively large loads. Dry wood should be up to indicators corresponding to 8-12% humidity. Its measurements are carried out using a special moisture meter.

It is necessary to dry the tree, observing certain rules. Otherwise, the material will be hopelessly damaged and cannot be used in construction. To do this, the wood must be stacked. And between each new layer should be placed gaskets from boards of the same thickness. Forest of any breed, laid in neat stacks, will never suffer from fungal infections, maintain its integrity and excellent consumer qualities.

Lao Czy member FORUMHOUSE

Gaskets need to be made higher so that air ventilation between the boards is better. They will dry out better. You can put on the edge your chopped whetstones 25 * 30 or 25 * 40. The reason for limiting the height of the stack is to prevent the boards from being driven by a "helicopter blade", fix the topmost layers of boards in the stack with self-tapping screws. For the third year, I have been storing my boards in this country house in the suburbs of Moscow in this way. They are in excellent condition!

Between the boards located in the same row, you should also leave spaces. This will ensure unhindered movement of air inside the stack and improve the quality of drying.

Wood Drying Chamber Project

Wood can be dried quickly and efficiently in well-equipped and freestanding drying chambers. The construction of such a camera on the scale of a summer residence or a suburban area is not always advisable. After all, such a type of construction will cost quite expensive, and its construction will take a lot of time.

The construction of such a premises can be called the implementation of a full-scale construction project. You can’t avoid the time-consuming operations associated with pouring the foundation, erecting walls and installing sophisticated equipment.

How to make drying for a tree can be understood from the diagram.

DIY chamber drying

Such a mini-dryer for wood requires the placement of not only the basic equipment (heating and ventilation), but also additional automatic control systems.

Operating modes of the drying chamber

A chamber dryer for does not imply strong heating during normal operation. And the full cycle of work related to the drying of one batch of wood can be divided into several stages.

The first stage lasts from 15 to 20 hours. During this period, the air in the chamber warms up to 45Co. The ventilation does not turn on, and condensation forms on the walls of the room.

The second stage lasts about 48 hours. It involves connecting ventilation and heating the air in a chamber dryer to 50 ° C.

The third stage lasts until the desired final moisture level in the internal structure of the wood is reached (8 ... 12%). At this time, the air temperature rises to 55 ° C, the exhaust flaps fully open, and the fans operate at full power.

After the humidity reaches the required values, the heat supply should be stopped. Fans should remain on for another 24 hours. As a result of this heat treatment, you will get dry wood that is completely ready for use during carpentry or construction work.

You can get acquainted with the practical practices of our members of the forum regarding the correct construction of the stack in the "" section. Those who wish to learn more about the technology of drying lumber can visit the "" section. Those who want to see a workshop on the technology of aging of wood, we recommend watching the corresponding video.

Once I experienced something similar. But now I know what needs to be done so as not to be in this position. Studying the subtleties of drying wood will protect you from future troubles, and will allow you to enjoy the process of using any available varieties of wood, and you will not be disappointed.

Wood is a wet sponge. It absorbs moisture and takes it from the environment. When a piece of wood is in balance in moisture content with ambient air, it is said that the wood has reached an equilibrium state of moisture content. Whether it was dried in an oven or simply on the street - this rule applies to all this.

Wood stored in a damp place becomes larger and wetter, and, conversely, dry air makes it drier and smaller. The trick is to ensure that your wood after construction is in balance with the interior dry air of the interior. Achieve this state should be before starting work.

The highest moisture content in wood - when the material leaves the sawmill, the percentage may exceed 30%. If you prefer air drying your material (my favorite way), you need to put it in a pack in a blown place, and do not forget to put gaskets between each layer of boards.

The shadow part of your plot is best. The garage most likely will not be ventilated enough for such work, as well as the basement. This is the first drying phase that will lower the moisture content of the wood to between 16 and 12%, depending on the climate in your area.

But be careful: after that, the wood will be ready to use afterwards, but this is not enough to avoid problems in the future. In most regions, wood should have from 7 to 9% water to avoid deformation and cracking during the winter season due to dry air from the stove, fireplace, and heating system. Thus, a second phase of drying the material is necessary, the passage of which will lead to these problems.

You can put lumber in a barn, an unheated garage or under a canopy and they still will not dry out for many years. To dry it you need a little warm air and time. And how much is determined by the thickness of the material, humidity after the first phase, temperature and moisture content in the air in your indoor environment.

Winter is the best time for drying wood, as The heated air in the house or in the warehouse is ideal for the second phase of drying. The process does not take much time if you follow the following rules. Allow the wood to dry after sawing it into separate boards and planing the edges. Treated surfaces require more thorough drying, this phase should be repeated after each series of carpentry work.

And, of course, use this time as efficiently as possible, leaving the surface of the material as open as possible. This can be done in an upright position or in a stack with gaskets. To speed up the process, place a home fan nearby. Additional air circulation will make drying twice as fast.

Once drying is complete, do not cut the material into smaller pieces immediately. It’s better to clean the room, and then, when the structure of the material has stabilized, you can plan it and so on. The next section shows how you can determine if your wood is sufficiently dried.

The ability to dry wood is not some kind of skill requiring great knowledge, but to avoid problems in the future, you can usefully apply all of the above.

Determination of moisture content in wood

The readings of the moisture content determinant are not an absolute criterion in assessing the quality of wood drying, but it can definitely help you. All models work on the same principle - the device induces a weak current through the surface of the tree and measures the electrical resistance.

The lower the resistance, the higher the moisture content. Indications are displayed on the analog or digital screen. Measure only freshly cut surfaces to evaluate precisely the performance inside the material. You can notice how quickly the wood dries, and guess the approximate end time of drying. I think such a device will be useful to you

When buying wood, we are usually interested in its moisture content. Nobody wants to buy raw lumber, because its use as a building or ornamental material is justified only in rare cases (for example, for pouring concrete).

Therefore, logging and processing enterprises usually sell wood that has already gone through the drying process.

What is wood moisture

During construction work and for the manufacture of wooden products, wood with a moisture content of not more than 23% is usually used.

• wet - humidity more than 23%;
• atmospheric dry - humidity 18 - 23%;
• air-dry (after artificial drying) - humidity 12 - 18%;
• room-dry - humidity 8 - 12%.

The lower, the less susceptible to the process of decay. In addition, after drying, there is an improvement in almost all the properties of wood that are important for use:

• its strength increases;
• deformability decreases;
•   grinding, gluing, staining;
• such indicators as electrical conductivity, heat capacity decrease, the heat of combustion increases;
• the density of wood is directly related to its moisture, the drier the tree, the lighter it is.

There is also the concept of equilibrium wood moisture. This means that at certain values \u200b\u200bof air humidity and its temperature, the humidity of the wood remains unchanged and tends to a certain value.

If these parameters change, the wood will either release moisture into the surrounding atmosphere or absorb it until the humidity reaches a new specific value.

Thus, in the process of drying wood, its moisture content is deliberately reduced to equilibrium values, depending on where and how lumber will be used.

Wood drying methods

All methods of excess moisture can be divided into the following types:

• natural drying;

The first way is known to all.   It consists in the fact that the lumber is stacked, where the rows are laid with gaskets, make a coating on top to protect from atmospheric precipitation and leave it to lie in the air. Due to the constant ventilation of the stack, the wood loses moisture and dries.

The second method consists in drying wood in special drying chamberswhere you can adjust the temperature and humidity. But this option is suitable for drying and is used mainly in woodworking enterprises.

What methods of drying wood can I use at home?

Even ancient masters knew how to perfectly dry wood to the desired condition. For this, many methods were used, some of which are relevant to this day.

Such an unpleasant property of wood is known as cracking upon drying. However, not all wood species are equally prone to cracking:

• alder, linden, birch, poplar and aspen - dry almost without cracks;
• larch, spruce, cedar, fir, pine - crack, but not too much;
• beech, hornbeam, maple, ash, oak - are subject to severe cracking.

This circumstance is the drying of each type of wood.

One of the famous folk drying methods is drying the tree directly on the vine. It is carried out as follows:

• At a distance of about half a meter from the ground, the bark is removed with a ring around the entire circumference of the chosen trunk. The width of the ring is approximately 1 - 1.5 m. A decrease in the width of the ring leads to an extension of the drying time.
• The removed bark stops the flow of moisture into the crown of the tree, while the foliage quickly consumes the remaining moisture in the trunk, thereby dehydrating it.
• The readiness of wood is determined by the degree of shrinkage of the leaves.
• When it is completely dry, the trunk can be cut off and used.

Drying the sawn trunk:

• The tree is cut down and, leaving a bark ring 0.7 - 1 m wide from the saw cut on the trunk, the rest of the trunk is left without bark. Cronus is not touched.
• The foliage left on the trunk quickly draws moisture out of it, effectively drying the wood.
• After 2 - 3 weeks, the trunk can be sawn and folded under a canopy for final drying.

Drying is carried out in the same way as in enterprises: on a flat, dry site, a floor is built, on which lumber is stacked. The upper row is laid with a slope and covered from precipitation.

To protect the ends of the material from decay, they are covered with lime, treated with a solution of sodium chloride or coated with liquid glue.

This method allows you to get rid of 75% of the moisture in the wood, but it is very slow:

• coniferous and soft hardwoods dry out within 1 - 1.5 years;
• hard rocks - more than 2 years.

Drying wood in a closed ventilated area.   To do this, you can use a spacious barn or a fairly high attic. Here is a stack of wood laid on laying than on the street. It is only necessary to ensure constant ventilation of the room.

Drying lumber on a cement floor.   This method is sometimes used to dry small volumes of lumber. It is laid out in a row on the cement floor and from time to time the boards are turned over. The method is based on the ability of cement to draw moisture from other materials upon contact.

Drying small wooden blanks and parts with newspapers:

• the blank is tightly wrapped in a dry newspaper and placed in a plastic bag, which is tightly wrapped.
• The bag with the workpiece is put in a warm place.
• When the newspaper becomes wet, it is changed to dry and the process is repeated until the workpiece reaches the necessary humidity.

This process usually lasts about 3 to 4 weeks. As the wood dries, newspapers have to change less and less. To speed up the process, the workpiece can be wrapped in a thicker layer of paper, but here - drying too fast can lead to cracks.

Drying blanks with sawdust or straw: blanks are covered with a thick layer of sawdust or dry straw and placed under a canopy. Sawdust and straw take moisture from the wood, but you do not need to change them, they quickly dry themselves.

Drying by steaming and boiling wood.

These are more complex methods, but they can be successfully applied at home.
  The steaming method is used to replace the moisture contained in the wood with vegetable oil. To do this, the workpiece is placed in a container with any vegetable oil and warmed over low heat for 6 -7 hours.

The steaming time depends on the size and thickness of the workpiece.   In earlier times, wood intended for the manufacture of wooden utensils was treated in this way. And the dishes turned out to be very durable, without cracks.

The method of digestion consists in prolonged curing of the workpiece in boiling saline (2 tablespoons of salt per 1 liter of water). Salt drives cell juice out of wood, replacing it. The saline solution itself is expelled from the wood much faster than water and without "serious consequences".

After boiling for 8 to 10 hours, the workpiece is removed, tied with a rag for 2 weeks, put in a dry place. When using digestion, you can simultaneously change the color of the wood. For this, coniferous sawdust is mixed in a saline solution. If the preform is large, then after drying in air, the digestion is repeated, then the preform is dried again. All this time, the harness is not removed from it.

If the products were made of wet wood, they can be dried using dry, clean river sand. To do this, the workpiece is placed in a container of suitable size, sprinkled with sand on all sides and put in the oven.

We examined the most drying wood at home. All of them require time and patience. So if you urgently need a dry blank or several boards, it will be more appropriate to purchase blanks of the desired moisture content.

If you are a home master craftsman and you have nowhere to rush, folk drying methods will be just right. After all, they almost 100% guarantee the correct drying of the wood, at which the risk of cracking is minimal.

Wood is a very popular building material, but it has one very unpleasant quality - shrinkage. Moreover, when dried, because the top layer dries faster than the inside, the wood can crack, bend. Therefore, you need to know how to dry the tree so that no unpleasant surprise occurs during or after work.

Process description

When drying in wood, two parallel processes take place. The greater the mass and volume, the longer the drying will take. First, the upper layers dry, while the inner layers dry, and moisture from the latter passes to the upper. If the material will continue to be used in a room with heating, then it should also dry out there.

You can check the moisture by compressing the chips in your hand. In a completely dry tree, they should immediately break. In production, humidity is determined using an electric moisture meter. The most suitable period for independent harvesting of wood will be the period from the moment of leaf dropping to the beginning of bud swelling.

The time required for drying up to 18-22% moisture content of lumber

Standing drying

Next, consider how to dry a tree on the vine. This must be done strictly from spring to the last month of summer. Having retreated from the ground 0.3-0.5 m, you need to remove the bark (1-1.5 m) around the entire circumference of the trunk. With this method, the tree dries quickly enough, and when the leaves fall, it can be cut down and sawn.

For trees in the forest, a different technique may be used. First you need to cut the tree, remove the bark by 2/3 of the trunk, stepping back a little from the saw cut. The foliage of the tree will consume all the remaining water from the bare trunk, and it will dry in 2-3 weeks. After cutting, such wood still needs to be held still for drying under a canopy, but in no case should it be stacked on bare ground.

Outdoor drying

It was discussed above how to dry a tree in the vine, then we will consider how to dry a tree in open space. To do this, you need to build a flooring at some level above the ground, covering it from rain and the sun. Felled trees are laid on it, and from the coniferous round timber it is not necessary to peel the bark, unnecessary cracks may appear. In the processing of the ends, lime, a salt solution, or liquid glue are used, this is necessary to protect against rot. With this method, of course, the tree will dry for a long time depending on the weather, humidity, thickness of logs or boards. Depending on the breeds, drying takes:

1. coniferous and soft deciduous - from 1 to 1.5 years;
2. solid - from 2 years.

Digestion and Steaming

In the old days, when there was only wooden dishes in use, they already knew how to dry a tree, and used such methods of drying wood as steaming and boiling. In short, we can say that the wooden blanks for dishes cooked. In the process of steaming - in vegetable (linseed) oil for 5-6 hours, the moisture should be shifted by the oil. And after that, the material should dry even under the sun's rays.

In the process of digestion, the preforms were boiled in water depending on the volume of water and the initial preform. And then you need to dry them inside a cool room. Each technology has its own subtleties and nuances.

Drying with newspapers and straw

For small pieces of wood, a method is suitable when they are wrapped in a dry newspaper and packaged in a plastic bag, then, as it gets wet, the newspaper changes to dry, and so on several times. This can last from 3 to 4 weeks, to accelerate, you can make the newspaper layer thicker, but the tree is characterized by the ability to crack when it dries too quickly. For accelerated drying, you can put the blanks in a newspaper in a warm place, for example, on batteries. Change newspapers every 2-3 hours, but here you need to make sure that no cracks appear. In this case, you can put it on the battery at night, and remove it during the day.

Straw drying is carried out according to the same principle, the only difference is that it must be carried out outdoors, having built a canopy to protect it from moisture. There is a big plus in that there is no need to change the straw every day, it dries itself. Sawdust or dry shavings can serve as an alternative to straw.

There are other ways to dry wood:

1. with a microwave, for small chunks;
2. drying in the sand;
3. under the influence of an electric field, placed between the electrodes;
4. by burying in grain closer to spring.

How to dry wood