Table of contents:
- Self-lining ovens
- How to choose clay for lining ovens
- How to prepare a clay solution
- Furnace tiles
Video: Self-lining Ovens
- Self-lining ovens
- How to choose clay for lining ovens
- How to prepare a clay solution
- Selection and preparation of tiles for cladding work
- How to cut a tile
- Facing stoves and fireplaces with tiles
The design of country houses, as a rule, includes the creation of stoves or fireplaces - a live fire in them is a tribute to our ancestors, a kind of connecting link between generations. As for the facing of stoves and fireplaces, this operation includes both decorative and functional tasks. Thanks to the finished lining, the furnace completely excludes the leakage of combustion products through the masonry joints and accidental cracks, and its heat transfer increases. And, importantly, it is easy to remove dust deposits from the lined surfaces - an operation that is important not only from the point of view of hygiene, but also from the point of view of household health, because when the oven heats up, the dust deposited on it actively releases toxins into the air.
The only thing is that stoves and fireplaces are difficult to cover, since most finishing materials and cement mortars will not work for this. Furnaces can only be lined with tiles or ceramic tiles, using a clay solution as a binding material. How to do this - see this article.
How to choose clay for lining ovens
First of all, clay samples must be tested for "fat content" and "dryness". This is done like this: place a clay sample in a container of water and stir it slightly - if the clay sticks to the spatula, it is too oily; if the blade is stained with only a thin layer, this clay sample is too dry. In the first case, to obtain a high-quality clay solution, you need to add fine sand, in the second - combine dry clay with more oily clay. High-quality clay, when placed in water and stirred, will stick to the spatula only in some places (i.e., fragmentarily) - it is ideal for facing work.
The second method of testing clay for suitability for facing work is to form bundles from it, about 200 mm long and 10 mm thick, by rolling them out on a board, like dough. Having prepared such a tourniquet, stretch it: oily clay will stretch like rubber and not crack when bending; dry clay will practically not stretch and will immediately burst, and when bent, a large number of cracks will immediately appear. High-quality clay will behave as follows - it will stretch a little, and show a mesh of cracks at the bend site.
How to prepare a clay solution
To do this, the clay must be placed in a metal or wooden trough and filled with water, leaving it in this state for three days. After the soaking period, you will need to thoroughly rinse the clay using your feet - put on your boots, climb into a container with soaked clay and rinse it until not a single lump remains. To reduce the fat content of the clay (if it is greasy), add portions of sand while working with feet - the result should be a creamy clay solution. I will warn you right away - this work will take considerable time and the quality of the clay solution largely depends on it.
It is a classic furnace cladding material, which is a decorative clay tile fired in a high-temperature furnace. The front side of the tile is decorated with a pattern and covered with glaze, the back side is made in the form of an open box - a rump.
Tiles are subdivided into cornice, corner and flat, their front side can be embossed or smooth, glazed (majolica) and unglazed (terracotta). The reverse side of the tile, made in the form of a box, is intended for attaching it to the surface of the furnace using steel pins and flexible furnace wire. Facing with tiles should be assumed even at the stage of creating fireplaces and stoves, sealing the ends of pins and wire fasteners into the masonry.
Selection and preparation of tiles for cladding work
As for the drawing, everything is individual here, the main thing is that it matches the general design and purpose of the room. When choosing tiles, it must be borne in mind that they all differ in color, some deviations in size, purpose and shape (depending on the place of installation - corner, cornice, etc.). Those. the concept of "marriage" in relation to this finishing material is applied quite flexibly - this feature of the tiles is associated with the technology of their production, which requires a significant share of manual labor.
Tiles purchased for cladding a stove or fireplace need to be sorted by size deviations, then you will need to give each group one size determined for it as a reference.
How to make the tiles the size you want? To do this, you need a sharp knife, with the help of which rectilinear tile shapes are formed. Curved lines are created using a sharp-edged curved steel plate. Moreover, the blows should be applied not with a hammer, but with a piece of pipe adapted for this - by tapping along the entire length of the cutting plate.
After removing the excess fragments of tiles, it is required to grind them on an abrasive stone with fine grain, giving the tile a light trapezoidal shape (the shorter side is the front). This operation requires special attention and accuracy, since there is a great threat of damage to the glazed front surface.
How to cut a tile
Sawing with a conventional tool, such as a notched knife, saw or grinder in the case of tiled tiles is unacceptable, since damage to its front side with such a tool is inevitable. The only way is this: along the line of the future cut, a light cut is made (up to 4 mm wide) using a sharpened cutter and a metal ruler, then a thin steel wire, about 1000 mm long, is used.
It is fixed from one end around any rigidly fixed object (usually a metal post), and the other end is wrapped around a wooden stick (just a wooden one!). The wire used to cut the tile should be of a smaller diameter than the width of the groove made on the tile with a cutter. A wooden stick with a wire fixed to it is placed on a stool, you need to sit on it and pull the wire string, moving the stool a sufficient distance. After that, proceed to the sawing operation: holding the tile with two hands and placing it in a groove on the wire, you need to move "towards yourself" along the wire string, slightly pressing the tile to the wire until the tile is sawn. Any attempt to reduce the amount of sawing work by incomplete sawing and hitting the cut will inevitably damage the glaze layer - so don't try to speed it up! Next is the line of grinding.
Facing stoves and fireplaces with tiles
The first thing to consider when deciding on tiling your stove with tiles is that this work, unlike facing with ceramic tiles, must closely follow the construction of the stove. The answer to the question “why” is because the wire fasteners for the tiles must be embedded in the oven masonry at the stage of the oven construction, otherwise they cannot be installed. If your stove has already been completed, and the tiles have not been tiled, then ceramic tiles will be the only facing option.
Facing the stove with tiles, view from the back of the tiles. a - tile details: 1 - plate, 2 - front side, 3 - holes for pins, 4 - rump. b - fastening tiles: 1 - brick, 2 - tiles, 3 - rump, 4 - pins, 5 - staples, 6 - wire knitting, 7 - loop.
The tiles have already been sorted and adjusted, and we are starting to install them. First of all, each tile must be moistened in water before installation in order to achieve better adhesion to the stove surface. The process of facing the stove begins with fixing the corner tiles in the bottom row - their edges should be thinly coated with clay solution, and a thick layer should be placed under the tiller. The entire lining of the stove depends on how much the vertical / horizontal position of the corner tiles will be verified - make sure in the most careful way in the ideal position of these tiles, using both horizontal and vertical building levels.
After installing corner tiles, lay a row of tiles dry between them, try them on in their place, sand some of them for the best fit to each other - this operation must be performed with each new row! After making sure that each tile is in the best position in the row, disassemble the row laid out dry and lay it out again, but this time on a clay solution, place only an open box of tiles (rumpa) - filling it completely, without voids.
Each next row of tiles should be separated from the previous one by a horizontal seam no more than 3 mm thick - this measure will allow the brickwork to which they are attached to settle down with them.
Each new row of tiles is carefully checked for horizontal / verticality, not allowing any deviations. When facing the stoves, the tiles should be completely adjacent to each other vertically - the vertical seams are not filled with mortar, since there should be no gaps in them. Horizontal seams must be filled with clay mortar.
The installation of intermediate tiles should be done as follows: we put the tile close to the corner tile and, holding it with one hand, fill the cavities between the trowels with clay mortar, pressing pieces of oven bricks into it (not heat-resistant, but oven bricks!) So that they adjoin each other as tightly as possible, without gaps. Any gaps or cracks will turn into air pockets and prevent the oven liner from heating up. As a result of this installation, a roller of mortar is created between each pair of tiles, fixing them in their places.
After laying two tiles on a clay mortar, it is necessary to thread steel wire pins into the existing holes of the tiller (wire thickness 4-5 mm, length 30 mm longer than the tiller height). To prevent the pins from sliding down, they must be bent from above with a hook, which will rest on the tiller. To completely eliminate the gaps between the tiles, you need to wrap the protruding ends of two pins of adjacent tiles with oven wire three times, insert a nail between the wire bundle and use it to twist, pulling the tiles together.
On the sides and bottom, you need to install staples on the trommel - they are made of furnace steel (thickness 2mm, width 15mm, length 100mm). It is important that the steel from which the staples will be cut is hard and springy - this is the only way to get staples of sufficient reliability. When installing the staples on the tines, it is necessary to make some effort to spread their ends to the sides - if the staples do not spring, then the whole point of their installation is completely lost.
Now you need to fix the tiles in the brickwork. To do this, fasten on each pin pieces of oven wire (two or three on each pin) so that they form loops. These hinges must be brought to the level of the brickwork so that they are clamped by the brick rows laid on top. Place the protruding ends of the hinges behind the brickwork. The lower cavities of the tiller should be filled with clay solution, pressing pieces of oven bricks into it, moistening them in water - there should be no voids in the trough cavity.
When laying stoves, it is tedious to lay the first row close to the tiled row, filling all the voids with a clay solution. After that, you need to attach the loops to the pins passed through the holes of the rump, put them on the laid out brick row and clamp the next row of bricks. Wire loops should fasten the tiles with each new row of bricks along the height of the tile. Since the hinges pre-installed on the tiles will significantly interfere with the work, put them in the course of masonry work.
After finishing the cladding, wipe its surface with a rag, removing dirt and clay stains. Prepare gypsum dough that is thin in consistency and spread it over the entire lining, paying special attention to the seams. Watch the plaster as soon as it sets - remove it and adhering dirt with a clean rag, leaving the plaster only along the seams of the cladding. For better cleaning of the tile surface, use soft paper - it will remove all particles of gypsum that are invisible to the eye. Gypsum in the seams between the tiles will highlight them in white.
Tips at last: the first row of tiles should be darker than the subsequent ones - this will achieve a smooth transition of the tiles from darker to lighter. Upon completion of the laying and lining of the oven, it is necessary to set aside two to three weeks for drying the oven - you cannot light a fire in it before the drying period expires.
Only a few types of tiles are suitable for this task - terracotta, majolica, clinker and porcelain stoneware. Terracotta is a tile with a colored base, created by pressing. It is highly durable and has a highly porous base. Majolica is produced in the same way as terracotta - the difference is that a layer of glaze is applied to this tile. Clinker tiles are made from a mixture of several types of clays, with the addition of chamotte and dyes. Its main characteristics are large thickness, high mechanical strength, low porosity and high temperature resistance. Porcelain stoneware, which has a monolithic and non-porous structure, has similar properties.
First of all, it will be necessary to prepare the surface of the stove and masonry joints for facing: in the first case, thorough cleaning of dirt and dust is carried out, in the second case, partial jointing of masonry joints to a depth of 10 mm is carried out. If the surface of the oven has been painted, you will need to completely remove the paint using a metal bristle brush or cover the surface over the paint layer with a wire mesh (mesh no more than 150x150 mm).
To attach the wire mesh, use 100mm nails by placing wide metal washers on them and hammering into the seams between the rows of brickwork. You can use the fastening on self-tapping screws by drilling holes for them in the brick (Drill D 4-5 mm). Before laying the tiles, a layer of cement-clay mortar should be applied to the surface of the furnace covered with a mesh (composition: cement: sand: clay, as 1: 0.2: 3 - use cement with a grade of at least 400).
Wait until the layer is completely dry and proceed with fitting and gluing the ceramic tiles. Before gluing each new row, adjust and trim the tiles (trimming is done with a glass cutter or a special ceramic tile cutter). For complete confidence in the horizontal position of the laid out tiles, mark the surface of the stove with a horizontal cord, the tension of which is provided by the load at its end.
The first row of tiles is laid out at the bottom of the oven. The application of the cement-clay mortar to the back of the tile is done with a spatula with rectangular teeth. The tile with the applied solution must be pressed to the surface of the oven with your hands, tapped, if necessary, with a rubber mallet. First of all, the whole ceramic tile is laid out, and the last one is cut.
To align the gaps, install the same plastic crosses between the tiles (sets of them are sold in any building materials store) - two on the vertical and horizontal sides of each of the glued tiles. When gluing, make sure that the seams are not completely filled - about half. This is necessary to give the cladding a better decorative effect.
Carefully monitor the position of the tiles, level it, if there are distortions - use building levels, and to check the planar position of the tiles - an even rail. When finished laying the tiles, wipe the surface of the cladding with a clean, dry cloth, removing mortar spills and dirt.
After 3 days have passed since the end of the ceramic tile lining of the furnace, the tile joints must be repaired. To do this, prepare a cement mortar that resembles plasticine in consistency, apply it to a rubber spatula and coat the seams. After another day, the oven lining is completely finished and the oven is ready for use.