Friends!
Those who deal with wood, process it and use it in any way are forced to deal with the problem of drying it. Drying wood is always relevant and pays off, because “wet” wood is much cheaper, and dry, ready-made wood is very expensive. It is necessary to remove excess moisture from the wood so that the process of uneven evaporation of water and juices does not occur, which is associated with the heterogeneity of the wood structure along the longitudinal and transverse fibers. But damp wood is unsuitable for serious processing, much less for construction, otherwise it will deform, crack, warp, and “lead.” How can you make a wood dryer with your own hands?

How to make a wood dryer with your own hands at home or in the country

If space permits, then it roughly looks like this:

1. First, we free up space in the kitchen near the stove or electric stove, fireplace, etc. You need to carefully calculate and measure how everything will function and look.
2. Partitions are installed from old doors and window frames, other available materials, for tightness everything needs to be adjusted and sealed. The size can be, for example, 2x2 or 3x3, depending on capabilities and needs.
3. Of course you have to leave it entrance doors and vents, and during drying keep them tightly closed so that there are no unnecessary drafts or simply excess air movement. Otherwise, this may lead to a less predictable drying process, loss of control over the process and loss of quality of the output wood.
4. The fenced-off area must be covered with insulation, all cracks must be sealed, plugged, caulked, etc. That is, to seal the space of the future dryer as much as possible to enclose the space and improve the quality of drying.
5. Since there is a high temperature near the stove or heating electrical appliance, then, if necessary, it is better to cover it with bricks that will accumulate heat and release it into the closed room. If the air does not circulate actively enough, a fan should be installed.
6. If you plan to dry a lot of wood or already finished products from it, you need to build strong metal shelves. It is better to secure it with anchors so that it can be loaded with serious weight.
7. To prevent the workpieces from bending, you need to fasten the edges of the material with pins. If the length of the wood is large, then several pairs of pins (3-4) are used. Of course, it is better to use wood of the same species, thickness, size and weight, otherwise drying will be very uneven. Be sure to lay out the material for drying with thin slats, bars, or gaskets for better ventilation. You need to carefully monitor the uniformity of temperature and air flow, then drying will proceed more smoothly and the quality of the output material will be higher. Moreover, it is more profitable to build several small dryers than one large one.

Do-it-yourself wood dryer, as a separate structure

1. First, a frame is constructed from an aluminum profile; it will not rust, is lightweight and durable.
2. Then it also needs to be sheathed with aluminum sheets, and thermal insulation 10-15 cm thick must be fixed on top. This insulation must be fire-resistant, strong and flexible. Roofing felt should be laid on the floor and sawdust should be poured on top.
3. Next, you need to ensure the tightness of the building and seal everything possible ways outlet of heated air. The tightness of the structure is of great importance for high-quality drying.
4. The boards intended for drying should be laid out in narrow (1-1.5 m) stacks and spacers made of bars should be placed between the rows and boards. And the height of the stack can correspond to the height of the room.
5. Drying can be done using, for example, fan heaters, which should be installed across the air movement. Or choose another drying tool suitable for individual needs and opportunities.

A simple effective way of tubeless infrared drying of wood from 1 board

If you don’t want to build a dryer yourself or you don’t have the opportunity to do this, then you can use a ready-made solution.

There is a relatively recently used method of drying wood using infrared radiation. The process itself is as follows: the wood is heated with infrared rays using a tubeless cassette dryer. What is the design of such a dryer? It consists of several thermoactive cassettes 1.5 mm thick. The cassettes are stacked in a stack of wood prepared for drying, alternating with spacer bars. That is, the coolant is already among the lumber intended for drying. Therefore, there is no need for a separate heat source, ventilation, maintaining precise parameters, or complex electronics and automation. The drying is controlled by a thermostat, which sets the required temperature for individual layers of the stack. For more optimal performance drying design, the stack is covered with a material with a reflective layer so that the condensate drains outside the stack. It is important that the process can take place both outdoors (preferably under a canopy to avoid possible precipitation) and indoors.

The advantages of this type of drying are

• ease of maintenance,
• equipment mobility,
• high rates (8% humidity can be achieved).
• high quality of the final material (no warping or internal stress),
• speed (from 3 to 7 days),
• variability, i.e. You can dry individual boards, or even just one, or entire large stacks.

You can watch a video about this technology here:

Drying wood from scrap materials. FlexiHIT.

Drying lumber in a tubeless cassette dryer

So, if you have a constant need for dry wood, then you can build a dryer, it’s not that difficult. Or buy a ready-made one and enjoy the finished dry lumber, which can be used to make various useful and interesting products.

If you have a large volume of unprepared wood that needs to be dried soon, you need to get a special dryer to carry out the initial processing of the material. This is a mandatory procedure during construction and finishing works, since if the material is damp, then problems will arise with its installation, and in the future other defects in the construction will appear. You will learn how to make a board dryer with your own hands from this article.

A little theory

Before you start making such a structure, you need to find out why you need to dry the wood. From the name it is clear that the design is designed to get rid of excess moisture from wood, however, you need to dwell on some theoretical points.

Wood moisture content

Wood moisture is divided into two groups:

1. Free, that is, located in cell cavities and intercellular space. The content of this moisture group is determined by the conditions in which a particular tree grew, as well as by how the cut pieces were stored. During drying, such moisture evaporates quite quickly.
2. Bound or structural moisture is the name given to the liquid that is part of the cell walls of a tree. The amount of structural moisture depends on the type of wood - this means that the length of drying can vary: trees, depending on the type, can get rid of bound liquid for several months or several years.

Important! Typically, wood is saturated with moisture by no more than 30%. Rocks with a high moisture content are called “gray” and are usually not used in construction.

Why is drying needed?

Before you make a wood drying chamber with your own hands, you need to decide what it is needed for. Let's do a little analysis and answer this question:

• When moisture is removed naturally, the configuration of the wood fibers changes, which is why the dimensions of the board are reduced.
• At the same time, the board loses excess moisture unevenly, which is why deformation occurs on completely different planes and at different speeds.
• Due to uneven “drying” inside the workpiece, so-called stress lines are formed, giving rise to cracks.

Important! Usually the board cracks along the grain, starting from the end. This happens because in these places the connections between the longitudinal fibers are somewhat weaker.

• Another problem is transverse deformation boards - the part takes on a completely unusual shape, arching like an arc or a “propeller”. This is due to the fact that the fibers dry unevenly and at different times, therefore their length decreases, also differing from each other.

Important! From the above facts it is clear that wood with a high moisture content may become unusable during poor drying. You can avoid this problem by preparing the raw materials and drying them on a homemade wood dryer.

Three drying modes

When you use drying chambers, you significantly save the time required to prepare the material for work. Moreover, you can control the drying modes by controlling the performance properties of the wood. On at the moment Over time, there are three modes of wood dehydration:

1. Soft. A special feature of this mode is the gradual increase in temperature in the chamber - due to this property, not only the pristine quality of the wood is preserved, but also its natural color. This drying method takes the longest.
2. Standard. IN this mode the wood retains its original strength, but the shade of the material changes slightly.
3. Forced. This mode is used if you need to dehydrate raw materials as quickly as possible, however, the quality of the lumber is significantly reduced. It is also worth noting that after applying this regime, the wood may darken and acquire a characteristic odor.

We make a drying chamber

So, we figured out what this structure is for. Now you can start making a wood dryer with your own hands.

Selection of premises

The first step is to wisely choose the room where the lumber will be dried. To do this, you need to follow these tips:

• The area of ​​the room should be based on the dimensions of the boards that require processing.
• The ceiling height should be 2-2.5 meters.
• The width of the room is selected by the user, however, it is worth considering that you need to leave room for a person to pass through.
• The windows in the room must be covered with bricks.
• The doors must be such that raw materials can be loaded into them without any problems.
• There should be a window or a small vent for ventilation.

Important! If you choose a large room, it is better to make a partition for thermal insulation.

Construction of a dryer

Usually a garage or barn is chosen as a place for a dryer, but sometimes it’s not even possible to use them. For this reason, it is important to know how to make a wood dryer with your own hands, using the drawings:

• Lay the foundation for the entire structure. Since the mass of the structure will be low, the foundation does not have to be deep.
• After the concrete has dried, you need to assemble a frame from a galvanized steel profile (you can replace it with an aluminum frame). Connect the frame parts using bolts and special brackets.

Important! Aluminum frame differs in its high price from steel, however, it has many advantages. For example, it is much more stable and is not afraid of corrosion.

• Sheathe the walls and roof with steel sheets fixed to the frame using special screws. To make the effect as effective as possible, you need to perform double cladding, placing a layer between two sheets mineral wool insulation, having a thickness of approximately 150 mm.
• Lay the waterproofing membrane on the floor, then cover it with sawdust.
• Install doors. They should close as tightly as possible.
• Build ventilation ducts or vents so that air can circulate freely.
• When the work is completed, check the tightness of the room. If necessary, correct any errors made.
• Equip an infrared wood dryer with your own hands. This point should be given due attention.

Equipment

Construction equipment instructions may vary. This is due to the fact that the camera equipment and material budget are different for each user.

Let's consider general scheme room equipment:

1. Make a support on which the stack of boards will be placed in the future. To do this you need to secure it to the floor. wooden structures, which allow you to raise the material approximately 20 cm above the ground. This is necessary for the circulation of air flow from below.
2. Can be used as supports for wall racks. To do this, you need to fix metal brackets on the load-bearing surfaces, which are designed for stacking stacks along the walls of the chamber.
3. Install the heating device. Its role can be played by a stove, heat fan, fireplace, heat gun and other structures - the choice depends on your desires and preferences. First of all, you need to pay attention to the power of the device - it is calculated from the volume of loaded lumber.
4. Install drying fans for boards yourself. The devices will provide movement of thermal air. Of course, you can get by with a regular hood, but then the drying time of the raw materials increases several times, which means energy costs will increase.
5. Arrange fans and air heaters so that the heated air passes across the air flow. This will reduce the aerodynamic system drag, which will make the dryer work more efficiently.

Important! Since you will need a lot of electricity, it is recommended to install a separate power cable for the structure. In addition, all the materials you use must be connected to the distribution panel via an RCD with the required power parameters. This is necessary in order to protect yourself from a possible fire.

If possible, you can install an automatic system that controls the temperature and ventilation of the dryer. This system provides high-quality drying of wood, so its high cost is justified.

Using the design

• You just need to stack the boards, placing bars approximately 20 mm thick between the rows, then load the stack into the room.

After this, you can change the temperature, gradually raising it.

Important! There are a huge variety of schemes, following which you can perform competent drying, but inexperienced users are better off using the low temperature mode first. This is due to the fact that its use is accompanied by a minimum number of defective boards.

Consider the classic process of drying wood:

• The temperature must be raised to 50 degrees, with a rate of increase of 6 degrees per hour.
• This temperature must be maintained for 5 hours.
• During drying, the moisture content in the wood must be reduced from 30 to 7-8%; to do this, it is necessary to maintain a temperature of 60 degrees for about two days. In this case, both supply and exhaust ventilation must be kept at half power.
• To condition the room, you need to keep the boards at a temperature of 60 degrees using actively working ventilation.

From this article you learned that making a wood dryer with your own hands is not so difficult, but for this you need to spend quite a lot of material resources and time. It is worth noting that all these costs are justified by their results, because in the end you get much more dried boards than if you bought ready-made lumber from the manufacturer.

All photos from the article

A do-it-yourself board dryer is made if there is a need to process a large volume of unprepared wood. Of course, you can immediately purchase blanks with optimal humidity, but in this case the costs of purchasing the material will be very high. So the construction special device may turn out to be quite effective from an economic point of view.

In our article we will tell you. How to dry wood, and we will give recommendations on how to independently arrange a drying chamber.

Theoretical aspects

Moisture in wood

Before we start designing a dryer, we need to understand why it is needed. As the name suggests, such devices are designed to remove excess liquid from wood, and here it is worth paying attention to the theory.

All moisture in wood is divided into two groups:

• free - found in cell cavities and intercellular spaces. The free moisture content is primarily determined by the conditions in which the tree grew, as well as the storage conditions of the sawn pieces. When drying, free moisture leaves the wood quite quickly;
• bound (structural) – a liquid that is part of the cell walls. Each type of wood normally has its own level of moisture content in the structure. In this case, the removal of bound liquid occurs very slowly, therefore, under natural conditions, drying can take from several months to several years.

As a rule, the limit of wood saturation with moisture is at the level of 30%. Wood with higher humidity is considered damp and is almost never used for work.

Humidity indicators for different materials differ:

Why is drying necessary?

So, we’ve dealt with moisture itself, now let’s analyze why we need to reduce it.

1. When moisture is removed, the configuration of the wood fibers naturally changes, resulting in a reduction in the size of the board - it “dries out.”
2. In this case, the workpiece loses moisture unevenly, so deformation can also occur in different planes at different rates.
3. Due to this, stress lines are formed inside the wood, which subsequently give rise to cracks.

Pay attention!
As a rule, the board cracks along the grain, starting from the end.
This is due to the least strong bonds between the longitudinal fibers.

1. In addition to cracking, transverse deformation of the board is also possible: the part either bends in an arc, or a so-called “propeller” is formed due to uneven raising of the edges. This behavior is explained simply: not all fibers dry at the same time, which means their length also decreases in different ways.

As you can see, if used to build structures or craft various designs wood with a high moisture content, over time, individual parts may become unusable. There is one way to avoid this - before starting work, prepare the raw materials by drying them in one way or another.

Drying modes

The use of drying chambers can significantly reduce the time required to prepare lumber for work. At the same time, by controlling the dehydration regime, we can control the performance properties of the resulting material.
Today, experts distinguish three drying modes:

Mode	Peculiarities
Soft	The temperature in the chamber rises gradually, due to which not only the natural strength of the wood is preserved, but also its color. At the same time, the rate of dehydration of raw materials is slightly reduced.
Standard	It is used to bring the material to its final moisture content while maintaining almost complete strength. In this case, a slight change in shade is possible.
Forced	Forced drying is used to prepare lumber for work as quickly as possible. After high-temperature treatment, the flexural, compressive and tensile strength is maintained, but the splitting strength may be slightly reduced. It is also possible that the wood may darken and a characteristic odor may appear.

Creating a drying chamber

Ready premises

1. We lay a tape or columnar foundation. Since the mass of the structure will be small, we make the base shallow.
2. After the foundation concrete has dried, we assemble a frame from an aluminum or galvanized steel profile. We connect the frame parts using bolts and special brackets.

Pay attention!
Price aluminum structures significantly higher, but at the same time they are significantly more resistant to corrosion in warm and humid environments.
So the use of more expensive load-bearing elements quite justified.

1. We cover the walls and roof with steel sheets, which we fix to the frame with metal screws (with a drill). For maximum efficiency We perform double cladding, laying a layer of mineral wool insulation with a thickness of 100 - 150 mm between the metal sheets.

1. We lay a dense waterproofing membrane on the floor, which we cover with a layer of sawdust.
2. We install doors that should close as tightly as possible. Can be reinforced for additional sealing door frame bars with rubber sheets attached.
3. As in the case of using a ready-made room, be sure to install ventilation ducts for air circulation.

After completing the work, we check the tightness of the room, if necessary, eliminating defects in the cladding. Now we just need to equip our drying chamber.

Pay attention!
A closed dryer should not have any gaps allowing uncontrolled air flow.
This is due to the fact that the presence of the slightest draft can provoke uneven processing of the boards, causing them to crack or deform.

Equipment

Instructions for arranging a dryer can be very different, because the equipment of the chamber largely depends on both our requests and financial capabilities.

And yet it is quite possible to formulate a general scheme:

1. First, we make supports on which the stack of boards will be installed. We fix it on the floor, allowing the material to be dried to be raised approximately 10-15 cm above the floor level to ensure circulation in the lower layer of air.

1. Instead of supports you can use wall racks. At the same time, we attach metal brackets to the load-bearing surfaces, intended for laying stacks along the walls of the drying chamber.

Pay attention!
This option is most often used when temporarily converting part of an outbuilding into a dryer.

1. Next, install the heating device. This could be a stove, fireplace, heat gun, fan heater, etc. – it all depends on your preferences. The key parameter will be the power of the device, which is calculated based on the volume of loaded wood: to dry 1 m3 of boards, at least 3 kW of thermal energy is required, respectively, the more raw materials we need, the more powerful the device we will need.
2. Together with heating devices, we install fans that will ensure air movement. Of course, you can save money on your purchase ventilation system and make do with natural exhaust, but in this case the time to prepare the boards for work will increase significantly, which means that the cost of heating the chamber will also increase.

1. We place fans and heating devices in such a way that warm air flows across the air flow. This installation can significantly reduce the aerodynamic resistance of the system, so that the dryer will work more efficiently.

Since for our camera to function we will need large number electricity, it is advisable to connect a separate power cable to it. In this case, we connect all used units to switchboard through an RCD with the corresponding power partners. Such a precaution will not be superfluous, since wood, even if not completely dried, can catch fire from the slightest spark that appears during a short circuit.

Advice!
It is also advisable to install an automatic temperature and ventilation control system.
It is quite expensive, but its use allows you to control the parameters of the internal environment of the dryer, thereby ensuring maximum quality of wood processing.

Using the dryer

If the drying chamber was assembled according to all the rules, then using it will be quite simple. To do this, we stack the boards, placing bars up to 20 mm thick between the rows, and load the stack into the dryer.

After this, we begin to change the temperature, gradually increasing the heat.

There are many drying schemes, but novice craftsmen should use a low-temperature mode, as it ensures maximum quality with minimal risk of defects:

1. Heating - raise the temperature to 45 - 50 0C at a speed of 5 - 70 C per hour.
2. Exposure – keep at 50 0C for 5 hours.
3. Drying – reduce the humidity of the wood from 30 to 8%, gradually increasing the temperature to 60 0C. This stage takes about 48 hours. Supply and exhaust ventilation turns on at half power.
4. Air conditioning – maintain the temperature at 600C for another 12 hours. Ventilation must work actively.
5. Cooling down to temperature environment with heating and ventilation turned off.

As a result, we should get boards suitable for most types of carpentry and joinery work.

Conclusion

As you can see, making a board dryer with your own hands is quite simple (but I must admit, with certain financial costs). Moreover, the use of this device allows you to obtain a large amount construction raw materials, which would be much more expensive if purchased from the manufacturer.

To learn more about the technology chamber drying We advise everyone who is interested in this topic to study the video in this article.

Any lumber is obtained by longitudinal sawing of a log. The result is bars, slats, and boards of various thicknesses necessary for construction and repair. Only dry lumber is used in construction. They have higher quality indicators. To dry wood at home, you can equip a special do-it-yourself lumber dryer. The construction process of this structure will take a lot of time. But as a result home handyman will always be provided quality material to perform various jobs.

The quality of the timber depends on how dry the wood is. The moisture content of the timber should be 12%.

Construction of a dryer

Construction simplest dryer for drying small volumes of wood with your own hands in natural conditions consists of several stages:

1. It is necessary to select and prepare an area to place the building. You can build a dryer on the adjacent building plot of land. For the construction of a dryer small size will do flat roof. The floor can be made from several layers of roofing felt, sprinkled with sawdust.
2. Wood to be dried is placed in a stack no more than 120 cm wide. Optimal size its width is 80 cm. The stacking height is 50-70 cm. Separate layers of boards or beams are laid with slats at least 2 cm thick. It is recommended to lay the stack across the air flow in this area.
3. Provides protection from rain and snow. Dry ones are placed on the top row of the stack. wooden beams cross section approximately 50x50 mm. Iron is placed on them, which is pressed against the same beams.

In such a dryer, the material is blown with air, the moisture gradually evaporates, and the humidity level decreases.

Drying chamber

The most efficient way to dry wood is in a special drying chamber. It can be installed automatic systems, which control the entire drying process of wood of specific species. At the output, the lumber will have a predetermined moisture level. You can also build such a camera yourself. But this building will cost a lot of money. For construction you will need:

• aluminum profile;
• sheet metal;
• thermal insulation material;
• waterproofing film;
• sawdust;
• heat construction gun.

Construction is carried out in the following order:

1. You should start with the construction of a foundation of any type. It can be piled or strip. For its construction you can use brick, concrete, metal pipes and other materials. It all depends on the size of the camera.
2. A frame is built on the foundation. The best way to do this is to use aluminum profile. It is assembled using bolts and nuts. Other methods of connecting frame elements are possible.
3. The finished frame is sheathed with aluminum or steel sheets. They are fastened using self-tapping screws, bolts, and welding. The walls can be made of brick, concrete, or other materials.
4. Thermal insulation is installed from mineral wool 10-15 cm thick.
5. The floor is covered with waterproofing film and sawdust.
6. To lay stacks of lumber, supports are prepared from bars in the form of a kind of well. This is done in order to raise the bottom row of the stack above the floor level.
7. Lumber prepared for drying is stacked through wooden spacers. Air should flow freely between the rows of boards. The height of the stack is limited only by the height of the ceiling.
8. For forced circulation of heated air, fan heaters or other heating devices are installed. The air flow should be directed across the location of the boards in the stack. This promotes a more efficient drying process.

Dryer inside the house

A small number of boards can be dried inside the house or cottage. The dryer is arranged like this:

1. You need to choose a room that has a fireplace or stove. Electric fireplaces and stoves can be used.
2. The room is separated from the rest of the house by partitions. Tightly closing doors are installed. A window may be needed for ventilation. All cracks must be sealed, since extraneous air flows and drafts negatively affect the quality of the dried material. It is also recommended to insulate the walls. On top of the insulation, they can be lined with brick, which well maintains heat from the stove and from electric heating devices. For forced circulation warm air install fans.
3. Raw lumber is stacked on specially made durable metal shelves.

Before drying, you need to check the moisture level of the material. This is done using a moisture meter. High humidity causes early wear and tear of buildings, the appearance of mold and mildew. Overdried wood becomes deformed due to moisture absorption and swelling. Wood is usually dried to a moisture level of about 8-12%. To prevent it from cracking, experts recommend treating the ends of the boards with a mixture of drying oil and sifted chalk. The consistency of the mixture resembles thick sour cream.

Lumber can be dried either with or without bark. You just need to remember that birch, aspen, poplar and beech in the bark can be affected by rot. In general, the drying process can last up to 2 weeks. During this time, temperature changes in the dryer should not be allowed. There should be a fire extinguisher in the dryer room. This is required by safety regulations.

Operating modes of the drying chamber

The camera should not be immediately heated to high temperature. In normal mode it works like this:

1. Within 15-20 hours, the air in the chamber is heated to approximately 45°C. The ventilation system is not working yet. Moisture should appear on the walls of the chamber.
2. When the temperature reaches 45°C, the supply air should be opened by a third and exhaust system ventilation. In about 2 days the temperature rises to 50°C.
3. The dampers must be fully opened and the temperature must be brought to 55°C. This is usually sufficient for a normal drying process. As soon as the humidity reaches approximately 8%, all dampers must be completely closed and the heat supply must be turned off. The fans continue to run for another day. Once the temperature drops to 40°C, dry lumber should be ready for use.

Additional equipment

As additional equipment You can install automatic equipment in the drying chamber. Its properties:

• the system is capable of working with cameras different sizes and with different sources heat;
• is relatively cheap;
• does not require special knowledge to maintain it;
• is easy to install;
• measures temperature and humidity in the chamber;
• provides fully automatic or semi-automatic operation of the drying chamber;
• automatically controls the operation of valves, dampers and fans.

To operate the system, it is enough to set the thickness and type of lumber and the desired final moisture content. The system helps dry various types of wood: pine, spruce, oak, birch, beech, linden, ash, maple, alder, hornbeam, poplar, aspen, sycamore. Every 2 hours, the automation takes readings of humidity and temperature and makes the necessary adjustments to the operation of all air heating and ventilation systems. Approximate cost Such a system ranges from $400-450.

Building a dryer with your own hands is quite troublesome and expensive.

But the result covers all costs. This is especially important for those who manufacture wooden products like furniture and wood carvings. Dry wood costs several times more than raw wood. In addition, in your own dryer you can achieve a certain moisture content of the workpieces. Everything can be done independently if you have a strong desire and the availability of a suitable place.

The drying process is the initial point in the entire preparation of the semi-finished product (wood) before processing.

Drying chamber for lumber and wood – great solution task, you can do it yourself. In order to avoid deformation of the logs, drying is carried out in specialized conditions, which are carried out exclusively in a drying apparatus.

Why is drying needed?

For a long time, when making any wood crafts, they used timber that had been cut down several years earlier. Products made from damp or under-dried boards will warp or develop numerous cracks.

When the tree dries out, it shrinks, the raw wood material will “sink” over time, and huge wide cracks will form in the log house. Under-dried semi-finished products are likely to develop fungus. But it is not advisable to overdry the tree, because it will begin to absorb water, which will lead to swelling.

What are the modes of drying chambers?

There is a whole list of drying modes for wood materials. In built with my own hands In machines, the mode from lowest to highest changes gradually, removing all excess water from the semi-finished product. The drying process is carried out based on the following material characteristics:

• wood species;
• overall dimensions of the semi-finished product;
• finishing and entry level humidity;
• specifics of the unit;
• quality indicators of lumber.

The drying process can be characterized by high temperature or low temperature. The second case is noteworthy in that the primary drying is carried out in a mode that does not reach 100ºC.

Low temperature conditions may be as follows:

• soft - after drying is completed, semi-finished products have their original properties without changing strength or color;
• moderate - the color changes slightly, the strength characteristics are slightly reduced;
• accelerated - during subsequent processing (breaking, sawing, cutting), increased fragility is possible, the color fades.

Change temperature regime Low-temperature processing is carried out in three stages.

High temperature processing is carried out in two stages. The second stage begins when the moisture level of the semi-finished product decreases to 15%. Such process used when further construction of secondary structures is necessary.

Main types of drying chambers

Drying of semi-finished wood products in industrial volumes is carried out in specialized drying machines. Moisture is removed from the wood by heated air, which subsequently escapes into the atmosphere. The device ensures a full drying cycle for lumber. The machine body can be:

• solid/prefabricated metal;
• made using building materials.

The latter are mounted directly in carpentry workshops in the form of a structure, or as free-standing ones. The walls are made using reinforcement and concrete mortar. As an alternative, you can use brick. Large factories make a system of cameras, combining them into entire modules with centralized control and communications. Air moves inside the dryer in a horizontal plane or vertically transversely.

Heat sources in the dryer:

• radiant source from specialized units;
• hot shelves;
• electric current that passes through raw semi-finished products;
• high frequency electromagnetic field.

The cameras are equipped with basic and auxiliary equipment. Basic systems:

• supply and exhaust equipment;
• heat sources;
• humidifiers.

Based on the principle of operation, drying machines are divided into:

• convective equipment;
• condensation equipment.

In convection machines, semi-finished products are “battered” with hot air waves, the heat is directed by the convection method. Travel time full cycle varies from 5 to 13 hours. Similar units are installed in large-scale sawmills.

Chamber-type dryers are more compact; a constant temperature and environment as a whole are maintained throughout the entire volume. This type of dryer will allow you to dry any type of wood material to the required condition, which is why many entrepreneurs who need to dry lumber choose chamber drying machines.

Based on the technology of the drying process, the moisture that is released from the wood settles on the cooling elements, is directed into containers and then drained. The efficiency of such a unit is quite impressive, but it is time-consuming and leads to large heat losses. The pricing policy of machines and the profitability of condensation drying are lower than convective drying.

Drawing

Drying chamber for lumber: step-by-step instructions

To build a drying apparatus with your own hands, you do not need to use technical documentation. You just need to provide:

• the area where the camera will be installed;
• insulation materials;
• source and communications for creating high temperature;
• blowing

The area of ​​a car built personally is usually no more than 10 square meters. A square-section room is more suitable for ensuring the movement of warm air flows. It is preferable that at least one of the walls of the equipment be concrete, the others can be made of wood. Inside the camera mandatory can be insulated. An excellent insulation material is wood shavings. If you don’t have foil on hand, you can replace it with penofol.

A separate extension for the dryer can be constructed from aluminum sheets; such a design will serve very well. long time. The base is made on the basis of profiles, it is covered with sheets of metal, which is then insulated. The thickness of the insulation must be at least 150 mm. The floor is covered with roofing felt material, a thick layer of shavings is poured on top, which will be excellent for heat conservation.

The heat source can be supplied as a heating pipe system. The liquid temperature in the pipes should be 60...90ºС. For an oversized chamber, having a two-burner stove would be quite acceptable. If the source is located directly in the room, it must be lined with bricks. Brick is capable of perfectly collecting heat and directing it to a machine for drying lumber.

Continuous circulation of liquid is important, which is provided by a compressor or an entire station. The room must be equipped with wet and dry thermometers.

For more convenient loading of semi-finished products into the chamber cavity, you can use a rail cart.

Video: DIY lumber drying chamber.