With your own hands, first of all, you need to take care of the quality of the materials used, because it depends on how long the construction will last. If you select low-quality materials, when heated, your stove can release carbon monoxide into the room, which will cause irreparable harm to the health of all family members.
For fireplaces and stoves, it is necessary to use a solution mixed on the basis of clay and sand, since this material can withstand the constant heat loads.
Solution composition
Clay cleaning
In order for the brickwork to be of high quality, the clay for the mortar must be cleaned of large lumps and debris. They do this in two ways: with alluvial and with a sieve. The sieve should be with cells no more than 3x3 mm, because it is precisely this thickness that the perfect seam has. The washing method is much more complicated, but the clay purified with the help of water is obtained better. Clay is poured into an oblong container (you can take a baby trough), set at an angle of 5-7 degrees, but so that it fills only the upper part, and water is poured into the lower part so that it does not come into contact with the clay. With the help of a scoop, water is pushed onto the clay until they are completely mixed. Then the solution is filtered, the operation is repeated until the required amount of building material is obtained.
Fig. 1 a - clay adheres strongly to the funky, too oily; fig. 1 b - separate clots remain on the jail - normal clay; fig. 1 c - the fungus is covered with a thin layer - skinny clay; fig. 2 a - a ball squeezed 1/5 of the diameter from lean clay gave cracks; fig. 2 b - a ball compressed by 1/2 diameter from oily clay cracked; fig. 3 a - flagella smoothly extended, sharp points at the points of rupture, no cracks when bent - too greasy; fig. 3 b - flagella smoothly extended, at the points of rupture a thickening of 20% of the initial thickness - normal clay; fig. 3 c - the flagella are slightly stretched, when bent there are many cracks - skinny clay.
Sand Selection and Processing
To make the process of passing clay through a sieve faster and easier, you just need to add more water to the bucket with clay.
Sand can also be bought in a store, or you can get it yourself on the slopes of ravines or on the banks of the sea or river. Typically, in stores this material is sold refined and ready to be added to the mortar for laying the furnace. But if you use non-purchased material, you will have to sift it in a sieve with a mesh width of 1.5x1.5 mm and rinse in the following way:
- Pull the burlap on the frame so that the sides are 50-100 mm high.
- Pour sand into it.
- Pour sand from the hose with water until the jet is relatively clean.
Solution preparation
After you have experimentally determined the amount of materials necessary for the solution and cleaned it, you can start mixing. By combining sand and clay, the solution must be filtered through a large sieve to get rid of lumps and clots. The finished mixture should slide well from the shovel, and not spread over it!In order for the mortar to be the most durable for laying the stove or fireplace, you can add cement or table salt to it. 3/4 liter of cement per bucket of mixture or 150-250 g of salt will be enough. Solutions with the addition of these ingredients are the strongest.
To find out how much mortar is needed, you need to know the rule: for 100 bricks, 2 buckets are needed. In the case of the laying of the Russian stove, this volume increases by 20%. The ideal solution will provide your fireplace a long service life.
- Types of masonry mortars
- Masonry mortar
- Mortar for laying the foundation and the outer part of the chimney
- Mortar for plastering
- Mortar for tiles
Not only the durability of the structure, but also its characteristics such as profitability and safety depend on how high-quality the solution for laying the fireplace turned out. If the solution spills up in the joints of brick or masonry without facing, carbon monoxide and other combustion products can enter the room and cause poisoning of people present in it. The reverse process (suction through the air from the room) is also undesirable, since it is accompanied by an increase in fuel consumption and a deterioration in the performance of the fireplace.
Types of masonry mortars
In the process of laying stoves and fireplaces, not one, but several types of mortar are used. They differ from each other in properties and purpose:
- The solution for the device of the stove or fireplace (main masonry) must withstand temperatures up to 1000 ° C.
- The solution for the construction of the foundation and the outer (street) part of the chimney must remain strong under conditions of high humidity.
- Finishing (plastering) mixture for facing the structure needs increased strength.
- The mixture for fixing ceramic tiles must have sufficient adhesive properties.
It is necessary to consider the composition, characteristics and method of application of each type of solution in more detail.
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Masonry mortar
Cement mortar familiar to all builders, on which almost all stone structures are built, cannot be used at high temperatures. Therefore, when building the main part of stoves and fireplaces, a clay-based solution is used.
Clay can be purchased at any hardware store. In this case, you will get a pure product, the composition and characteristics of which are reliably known. Clay can be obtained in another way, free, but troublesome: dig it in the wild. Layers of clay lie at a depth of only 0.5 m. It is most convenient to collect it on the slopes of ravines or along river banks. The inhabitant of the city blocks is enough to find a place for earthworks: there, most likely, he will be able to collect clay in the required volume.
Clays are divided into three varieties:
- skinny
- normal
- greasy.
The solution, prepared on the basis of lean clay, after drying becomes brittle and crumbly, it is absolutely unstable and does not provide adhesion to masonry. Fatty clay must be added to such a solution.
A mixture based on only oily clay after drying gives significant shrinkage and may crack. To normalize the fatty solution, sand must be added to it.
How to determine exactly what clay you got and how much sand you need to add to it? All this can be determined experimentally. Clay taken in a volume of 1 liter is cleaned of large impurities and divided into five parts. The first part is left in its pure form. Sand is added to the second, the volume of which is 4 times less than a portion of clay. Then sand is added in the following proportions: to the third part - half the volume of clay; to the fourth part - the whole volume; to the fifth part - one and a half volumes of clay. Then water is added to each container, and their contents are thoroughly mixed. The finished mixture should be uniform and flexible, but should not adhere to the skin. This solution is called "cool dough."
From each portion of the solution it is necessary to make a ball that fits between several polished boards. Press one of the boards until cracks appear on the ball. If the clearance between the planks was reduced by 50%, the solution turned out to be oily. If within one fifth, you are dealing with lean clay or excess sand. A normal solution, suitable for laying stoves and fireplaces, will begin to crack when the boards approach one third of the original distance.
Clay is filtered through a sieve with a 3 mm cell. This cell size is due to the thickness of the seam in the masonry, which is 3-5 mm. Thus, it is advisable to filter out precisely those particles whose sizes exceed 3 mm, otherwise they will interfere with the construction of a normal joint in thickness.
More effective is the alluvial clay cleaning method. For its implementation, you will need a long container like a trough or a baby bath. Having established a container with a certain slope (within 7 °), a small amount of water is poured into it, and a portion of clay is poured into the upper part. The volumes of water and clay are selected so that they do not come into contact with each other. Now, using a spatula or other flat tool (such as a construction trowel), water should be pumped onto the clay, which will be washed and deposited in the lower part of the container. After this, the clay will only drain.
For a clay solution, fine-grained sand with a grain size of no more than 1 mm is needed. The most suitable is mountain sand, the deposits of which lie on land. Unlike sea or river sand, which has a smooth, water-polished surface, mountain sand is rough, which makes the solution more durable.
Before preparing the solution, the sand should also be washed. It is convenient to do this with a homemade tool resembling a sieve: a square box is knocked out of four boards with a width of 50-100 mm, the bottom of which forms a stretched burlap. Having poured a portion of sand into such a "sieve" mounted on a support, they begin to pour it from the hose with water, which, along with dirt, flows through the burlap. The washing quality is evaluated visually by the purity of the water flowing out.
How much clay and sand should be prepared? On average, a solution for laying stoves or fireplaces occupies a volume that is 8 times less than the volume of a brick or 10-13 times less than the volume of the entire structure, calculated according to the external dimensions. Thus, a masonry of 100 bricks of a standard size will need about 25 liters of mortar.
To prepare the solution, the purified clay should be soaked. This should be done in a container or on a specially constructed wooden platform with an area of 1.5 x 1.5 m. Clay is poured in layers, pouring water on each layer. The thickness of one layer is from 100 to 200 mm. After the clay is saturated with water and becomes soft (it may take about a day), it is mixed with a bayonet shovel, if necessary, again filled with water and left for another day.
If in 10 l of clay solution add 100-150 g of ordinary table salt, it will become more durable. For the same purpose, 0.5-1 kg of Portland cement, which can be either in dry form or in the form of a solution, is added to this amount of the mixture. Clay mortar with the addition of Portland cement should be prepared in small portions, because after an hour from the time of mixing it becomes unsuitable for work.
The working conditions of the solution located in the foundation or in the outer part of the chimney differ sharply from those in which the solution of the main masonry has to work. There are no high temperatures, but there is increased humidity. In such an environment, lime or lime-cement mortar has the best characteristics. The composition of this mixture includes lime dough, cement, sand and water. The lime dough must be filtered through a sieve with a mesh size of 3x3 mm, it can also be used to sift sand. On average, 2-3 parts of sand are added to one part of the lime dough.
The calcareous composition, like clay, can be lean, normal and greasy. Check it with a wooden spatula. After 3 minutes stirring, you need to see if the solution sticks to the scapula. If not, the solution is skinny. If a layer 2-3 mm thick is formed on the blade or the solution sticks in the form of clots, then it is normal. A greasy solution will cling to the instrument with a thick layer. Lead skinny solution to normal plasticity can be by adding lime test. Sand should be added to greasy.
Ready lime mortar remains suitable for construction work for several days.
Everyone who is familiar with construction work will be able to lay down a stove or fireplace of a simple design with their own hands, if he has at his disposal a detailed description and layout of the rows - order. But laying a fireplace with your own hands is impossible without knowing what materials can be used, how to choose or cook them.
Even a person who is far from furnace business will say that a brick and mortar are needed to build a fireplace. But what kind of brick, and what should be the right solution? This is a matter of paramount importance, to neglect which is to waste your energy, time and money in futile work. We will figure out how to choose materials and how to lay down a fireplace.
Brick
Types of bricks for laying fireplaces
Do-it-yourself masonry of the fireplace using solid red clay bricks. It is used to build the outer part of the fireplace, and for the facade you should choose smooth bricks of the correct shape without chips and cracks.
For that part of the stove or fireplace that is in direct contact with open fire, a special refractory fireclay or quartz brick is selected.
A hollow facing brick can also be used, but only for laying the pipe head above the roof or for facing a finished fireplace.
Brick Quality Requirements
Before you fold the fireplace yourself, you should make sure that the material is selected correctly.
When choosing a brick, the following requirements must be observed:
- Give preference to brand bricks not lower M 200. Products of this brand look better in appearance than brick of lower grades, and, most importantly, they have high strength, withstanding the permissible load 200 kg / cm².
- Buy immediately the required amount of brick, so that it is all from one batch and has the same characteristics.
- Assess the external state of the brick: the absence of cracks, chips, the presence of battle in the pallet.
Solution
Solution composition
Conventional cement mortar is completely unsuitable for the construction of structures experiencing high thermal loads. The mixture for laying the fireplace is made on the basis of clay and sand, and their percentage depends on the clay content.
Cement may also be present in such a solution, but in a very small amount.
- The solution must be homogeneous, without lumps, and have normal ductility. Only in this case, he will firmly bind the brickwork, does not crack upon drying and will give a little shrinkage.
- Too plastic mortar based on greasy clay is perfectly leveled on brick, allowing you to make the seam beautiful and thin, but it is not suitable for furnace work, since during operation gives great shrinkage.
- A low-plastic solution based on skinny clay practically does not shrink, but does not provide good masonry strength, cracks and spills out of the joints when dry.
Sand and clay quality requirements for mortar
The sand should be clean and shallow. It is best to use mountain or river sand sifted through a fine sieve to clean it of large inclusions and vegetation. This procedure will create a high-quality homogeneous solution and get a thin and even masonry seam.
Only experienced stove-makers are able to determine the quality of clay by touch. But there are many ways, both folk and laboratory, to check whether the clay is suitable for the preparation of a stove solution, and to determine the optimal ratio of clay and sand. Here are some of the easiest ways:
How to prepare a solution?
Having determined experimentally the ratio of sand and clay, measure the required amount of materials and sift them. Sand - in the usual way, and the clay is pre-soaked with water, mixed thoroughly and filtered through a sieve with small cells.
After mixing clay and sand, the solution is filtered again through a larger sieve to make it homogeneous, without clots. The finished mixture should not spread on the shovel, but slide well with it. From such a solution, ideal seams are thick 3-5 mm.
To increase the strength of the mortar, cement ( ¾ liter per bucket of solution) or table salt ( 150–250 g) Cement is diluted with water before adding to the consistency of sour cream, the salt is also dissolved in water.
How much mortar is needed for laying fireplaces?
To lay 100 bricks flat, stitching along 5 mm, you will need two buckets of mortar. When laying the Russian stove, this amount increases by 20%.
Attention! It is very important to prepare a solution of the desired plasticity and density! Only such a solution will fill in all the bumps, ensure the density and gas tightness of the joints and the strong adhesion of the bricks.
How to fold a fireplace with your own hands?
Having prepared the necessary materials, you need to solve the main question, how to lay down the fireplace.
To lay down a stove or a fireplace (see Brickwork for masonry fireplaces), you will need to make a solid base and prepare masonry schemes called ordering.
Foundation preparation
If the floors in the house are made of reinforced concrete slabs, laying a fireplace with your own hands does not require the construction of a foundation. In all other cases, it is necessary to do it in order to ensure stability of the fireplace and to avoid its destruction.
Important! The base for the stove or fireplace should not be connected with the foundation of the house!
Orderings
Ordering is a very detailed diagram that shows the position of each brick. Note that the ordering is done separately for each row of masonry.
Only an experienced craftsman can lay down a fireplace without ordering, but a novice will not be able to correctly perform work without it. Therefore, the order should be prepared independently, and it is even better to order a scheme for your fireplace for a good stove-maker.
Work technology
On the base of the fireplace, under the first row of masonry, it is necessary to lay two layers of waterproofing. The basement row is usually laid “on the edge” so that it is higher than the level of a clean floor. In all subsequent rows, the brick is laid flat.
Before laying, the bricks are soaked for 2-3 minutes in water to ensure a more tight contact with the solution.
The bottom of the fireplace insert should be located at the height of two or three rows of masonry from the floor.
If you decide that you can do the laying of fireplaces with your own hands, you must consider the following: red and refractory bricks have different linear expansion parameters when heated.
Therefore, there are some features of their simultaneous use in a single design. Since the fireplace insert is made of refractory brick, which gives a greater linear increase, during operation it can cause the destruction of the fireplace body, made of red brick.
To prevent this from happening, it is necessary to use “dry joints”, that is, lay out the fireproof insert of the fireplace without dressing with the external walls, departing from it at least by 2-3 mm.
In this case, the furnace is provided with freedom for expansion, and the space between the masonry creates thermal resistance, not allowing the fireplace body to become very hot.
Particular attention should be paid to laying masonry over the furnace opening. It is undesirable to use metal or reinforced concrete lintels, which can deform strongly when heated.
Lay out a brick in the form of an arch or even horizontal overlap, and with a certain ledge, using a special formwork.
There are several options for laying floors:
- bladed
- arched
- onions.
In any case, before starting work on the laying of the floor, it is necessary to make the formwork, which must exactly match the lower contour of the firebox arch. The formwork is designed so that after hardening the mortar it can be lowered and removed without effort without damaging the masonry. To do this, it is supported by bars in the upper part.
Arched and beam bridges are laid out on the formwork flat, and for the device of wedge-shaped floors, the brick is turned on the edge. The thickness of the joints between the bricks at the bottom is about 3 mmand at the top - 25 mm and more.
The bridge is laid on both sides and ends with the installation of a central brick, which is placed strictly in the middle of the arch vertically. Of course, the brick for the masonry of this part of the structure must be selected especially carefully.
Fireplace trim
About what materials will be used for decorative decoration of the fireplace, you need to think in advance (see. Decoration of the fireplace). If you want to leave the fireplace unclad, you should lay the brick very carefully, without bringing the mortar to the front of the masonry by half a centimeter. Subsequently, the seams can be embroidered.
If the masonry was not very beautiful, then the fireplace can be completely plastered or faced with natural or artificial stone, ceramic tiles, tiles. Finishing will hide all your flaws and defects of the brick, allowing you to do without rework.
Clay, lime, mixed mortars, as well as heat-resistant concrete mixtures for laying stoves and fireplaces.
Solution - a mixture of binders, aggregate and water. According to the density in the dry state, they are divided into heavy (1500 kg / cubic meter or more) and light (less than 1500 kg / cubic meter). According to the purpose, the solutions are masonry (for laying brick, stone and blocks of furnaces), finishing (for finishing furnaces) and special.
The aggregate together with the binder and water creates a solid foundation and a monolithic body of the furnace and chimney. It reduces the shrinkage of the solution (for example, slag aggregate). According to the type of cementitious materials, solutions are divided into cement, lime, gypsum and mixed (cement-lime, lime-slag, etc.).
Simple solutions consist of one type of binder and aggregate, complex or mixed, of two or more binders (cement and clay, cement and lime) and aggregates. For example, a cement-lime mortar with a ratio of 1: 3: 15 consists of one part of cement, three parts of lime paste and 15 parts of sand.
In complex solutions, the volume of the main binder material is conventionally taken as a unit, the remaining components (binders and fillers) are expressed by numbers showing how many volume parts they take on one part of the main binder. The main substance has stronger astringent properties, so the name of complex solutions begins with the name of the main binder. For example, a lime-clay mortar in its composition has two binders - lime and clay.
Clay solution collapses under the influence of moisture, it is not suitable for laying foundations and chimneys over the roof. These parts of the furnace are performed on lime, cement or lime-cement mortar.
Clay mortar for laying stoves is used only in a dry place, while the seam should be 3-5 mm. The solution from a thick seam quickly crumbles, air is sucked into it, which impairs the operation of the furnace and causes excessive fuel consumption. Thin seams can be obtained only from good clay and a thoroughly mixed solution, filtered through a sieve with 3x3 mm cells. Sand for mortar should be fine, grain size - not more than 1 mm.
Skinny solutions do not have the necessary plasticity and strength, fatty - plastic, but form cracks when dried. Most suitable for masonry are solutions of medium ductility, or normal, in which the binder and aggregate are in the optimal ratio. They are durable, do not crack upon drying and give minimal shrinkage.
Lime, cement and complex solutions are applied to the masonry only with tools.
Before preparing the clay solution, the clay must be checked: in 0.5 kg it is added a little water and knead thoroughly with your hands until it has completely absorbed the water and sticks to your hands. Having prepared a cool dough, roll a ball with a diameter of 40-50 mm, make a cake with a diameter of 100 mm from the same ball and dry them for 2-3 days. If cracks appeared on a ball or a cake during this time, the clay is oily and requires the addition of sand. If after drying on the ball and the cake there are no cracks, and the ball, falling from a height of 1 m, does not crumble, then clay is suitable for preparing a solution. Skinny clays do not crack, but do not have strength, more fatty clays must be added to them. Sand or clay is added in several stages, each time checking the quality of the solution.
Another way to check the quality of clay: take 2-3 kg of material, visit the dishes, pour water, knead the lumps and mix. If the clay strongly sticks to the shoulder (completely envelops it), it means that it is oily, it is necessary to add sand to it. If individual bunches remain on the blade, the clay is considered normal, and a solution is prepared from it without the addition of sand. If the blade is covered with a thin layer of clay, it means that it is skinny and requires the addition of greasy clay.
You can check the quality of the clay like this: 0.5 kg are kneaded to a stiff dough and carefully kneaded with your hands. A ball of 40-50 mm diameter is rolled out of clay dough, it is visited between two smooth plates and gently press the top one, gradually squeezing the ball until cracks form on it. The applied force and the amount of flattening of the ball, as well as the nature of the cracks formed, indicate the fat content of the clay. A ball made of lean clay (loam), with a slight pressure splits into pieces. The ball of clay is more fat, loam, when compressed by 1 / 5-1 / 4 of its diameter gives cracks. A ball of normal clay cracks when compressed by 1/3 of the diameter. The ball of oily clay gives fine cracks in compression by 1/2 of the diameter.
From such clay dough as a ball, flagella is rolled by hand with a thickness of 10–15 mm, a length of 150–200 mm, and stretch or bend in the shape of a ring around a round and smooth wooden rolling pin with a diameter of 40–50 mm. Oily clay flagellum smoothly, gradually thinning, forming sharp ends at the point of rupture, and no cracks are formed when bent. The flagellum from normal clay is pulled out smoothly and breaks off when its thickness at the point of rupture becomes less than the thickness of the flagellum by 15-20%, and when bent, small cracks are formed. Flagella from thin clay does not stretch a little, gives an uneven rupture, and when bent, many cracks and ruptures are formed.
Clay mortar for furnace masonry requires from 1/10 to 1/13 of the furnace volume, counting by its outer size, or up to 1/8 of the volume of the brick being laid - an average of 25 liters (2.5 buckets) per 100 pcs. brick. Clay mortar should not differ from the composition of bricks and tolerate heating up to 800-1000 degrees, without losing strength or emitting harmful fumes. The less clay in the kiln, the higher its quality. The best solution is clay, from which brick is made. For the preparation of the solution, you can use the raw brick. The solution must be plastic. The greasy solution dries out, decreases in volume and cracks, the lean does not provide sufficient strength, binds the brick poorly and easily crumbles out of the seams.
The strength of the clay solution is increased if 100-150 g of salt is added to one bucket. The fine salt is mixed with the solution, and the coarse is dissolved in water beforehand. Sometimes a solution of 0.5-1 kg of portland cement is added to the bucket, mixing it in a dry form or previously shut off with water. Apply this solution no later than one hour after preparation.
To prepare the solution using different clay, mixing it in a dry form, then shut it with water. 0.5-5 parts by volume of sand are added to the thick clay. It is sifted through a frequent sieve with 1.5 × 1.5 mm cells. Very thin clay is soaked - washed in water, removing excess sand from them.
If clay fluid is normal, no sand is required. For the preparation of a clay solution, a wooden plank with a size of 1.5 x 1.5 m is made, on which layers of clay are poured and moistened with water. When the clay softens, it is shoveled several times and raked in a pile in the form of a narrow bed 300-350 mm high. Then thin plates are cut off from her with the edge of a wooden shovel, and the lumps are broken and crumpled. Stones and impurities are removed. Then the mass is shoveled, raked into the garden bed and again crushed with a shovel 3-5 times, until all the clumps are broken.
If in the process of working it is required to add sand to the clay, then pour it in the form of a wide bed, make hollows in it, then pour the clay in layers, moisten it with water and cover it with sand. Stand up time until the clay softens, then repeatedly shovel with sand, collected in a bed and crumpled with a shovel until it is completely mixed with sand and becomes homogeneous. A well-mixed solution with the right amount of sand and water should slide off the iron spade, but not spread over it, to the touch it is a slippery mass with uniform filling with sand without clay or sandy clots. In such a solution, large particles often remain that do not allow thin seams to be performed, therefore, during its operation, it is necessary to feel all the time with hands, removing foreign particles, which slows down the work. Such a solution is advisable to strain through a sieve.
The optimal ratio of clay and sand in a clay solution is 1: 1 or 1: 2. The amount of water is 1/4 of the volume of clay.
Clay of normal fat content, which does not require the addition of sand, is poured into a box or barrel in layers and moistened with water, where it is soaked for several hours. Then it is thoroughly mixed and filtered through a sieve with 3x3 mm cells. Water is added to the workplace, reaching the required thickness of the solution.
If sand needs to be added to clay, it is measured at the required dose and sieved on a sieve. After disintegration of clay, it is filtered, sand is added, mixed and filtered again.
Mortar Prepared from lime dough, sand and water. It is used for laying the foundations of furnaces, as well as pipes above the roof. To give strength to the solution, cement is added to it, and for quick setting - gypsum (in plastering works).
To prepare the solution, the lime paste is filtered through a sieve with 3x3 mm holes, and sand is sifted through it. If the dough is too thick, it must be stirred with the addition of water. Sand is added and the whole mass is thoroughly mixed until homogeneous. The amount of sand depends on the quality of lime: from 0.5 to 5 parts by volume of sand (usually 2-3 parts) are added to one volume part of the lime paste.
To determine the quality of lime mortar it is mixed with a wooden oar for 2-3 minutes, if the solution does not stick to the oar, it means that it is thin; if it sticks in places in the form of individual bunches or covers the paddle with a layer of 2-3 mm - normal, if the solution sticks with a thick layer, it means that it is greasy. It is necessary to add calcareous dough to a thin solution, to fatty sand. Lime solutions can be stored for several days.
The better the lime paste, the higher the quality of the solution, and vice versa. Therefore, a lump of boiling lime is quenched by filling it with water and keeping it in creative boxes until it is completely extinguished. From this operation depends on the quality of lime and the maximum yield of lime test. Slaked lime can be poured into any dish, but better into a creative pit dug in the ground, lined with planks, where it can be stored for a long time, if it is covered with earth above the layer not thinner than 50 cm. The longer it is stored, the higher the quality, but without access of air. Drain lime through a sieve with cells of at least 5x5 mm.
In order to cook the quick-burning lime, water is poured into a quenching box at half its height. Then it is filled with lime in several stages, evenly distributing it. When steam appears, it is stirred vigorously, breaking up the individual pieces and adding water until the vapor evolution ceases. Water is added to the slaked lime in order to obtain a homogeneous milk of lime, and left for some time to extinguish the remaining pieces. Then the whole mass is mixed and filtered through a sieve.
To extinguish the lime that has been quenching, pour lime into the quenching box — the kettle is a quarter of its height and filled with water to half a layer. When steam appears, they start mixing up the lime while breaking up the pieces. Water is added in small portions to prevent lime from drying and burning out. After cessation of steam release, water is added, all is thoroughly mixed, and the milk of lime is drained after some time through a sieve into a dish or a sprinkling well.
Slow-burning lime is poured into a quenching box for a quarter of its height, moistened with a small amount of water and kept until cracks and other signs of extinction appear. After that, it is watered in small portions and mixed. After slaking, the lime is diluted with water to the thickness of milk of lime, kept for some time and poured through a sieve for storage. In the cold season, slow-burning lime to speed up the quenching is poured with hot water.
Leftover lime remains are piled up separately and filled with water, leaving for some time. Part of it can be extinguished. Slaked lime is recommended to endure to use for at least a month: its quality is improved, the more lime paste is maintained.
Cement mortar - the most durable, it hardens in air and in water. Prepared from cement, sand and water. It is used for laying foundations in wet places or soils saturated with water, as well as pipes above the roof. The cement mortar quickly sets (the start of setting is 45 minutes, the end is no later than 12 hours). It is applied no later than an hour from the moment of preparation, with longer periods it reduces its strength. Brand, or the strength of the solution in compression, is different and depends on the number of constituent materials, as well as the brand of cement. The composition of the solution is from 1: 1 to 1: 6.
To prepare the solution, cement and sand are sifted through a sieve with 3X3 mm holes, measuring them in bulk doses. The right amount of sand is poured with a thin layer and sprinkled with cement on top, stirred until complete homogeneity, sometimes additionally sieved through a sieve. In the dry mixture pour water to the desired thickness.
Difficult solution Prepared from two binders and one aggregate: cement, lime and sand. Used for laying foundations in damp soil and pipes above the roof. One to three parts of lime dough and from six to fifteen parts of sand are taken for one part of cement.
The solution is prepared in two ways. A dry mix is made from cement and sand, then lime dough is diluted with water until thick cream. These materials are pre-measured in exact volume doses. In the diluted lime paste add cooked portion of the cement mixture, mix everything thoroughly. To obtain a solution of the desired density, add water and mix again.
Another way: a solution is prepared from a measured amount of sand and lime dough, a portion of cement is poured into it and everything is thoroughly mixed. Cement can be pre-mixed with water to a creamy state. Such a solution is more plastic than cement, but it is lower in strength. It must be stored in such quantity to use in the case for an hour from the moment of preparation.
Heat-resistant concrete mixes used for the manufacture of monolithic foci of open fire or blocks for laying stoves and fireboxes. Technology of preparation - as well as cement-sand mortar. The use of concrete, as a rule, requires the construction of the formwork and keeping it up to 28 days in the wet mode. Freshly laid concrete (in formwork) is covered with matting or chips and moistened abundantly with water, especially during the first three to five days. Good results are obtained by using a polyethylene film for this purpose (vapor effect).
The compositions of heat-resistant (fire-resistant) concrete in bulk parts:
For open fires
For the firebox