Silicone molds for decorative tiles. Polyurethane forms. Purchase from the manufacturer

Artificial stone appeared on the market relatively recently, but immediately appealed to everyone involved in construction or renovation. This is a very attractive facing material. With its help, you can easily and quickly improve the facade of a building or a personal plot. Get it filled liquid solution in a special form. The hardened solution turns into tiles with a natural texture.

Description

In appearance, this material is very similar to natural rocks . The tiles obtained from a hardened special mortar have proven their practicality and durability.

Natural minerals, when external conditions, temperature, humidity change, change their properties and characteristics, which is reflected in their appearance. The weight of natural stones increases foundation load or walls.

Artificial stones are free from all these disadvantages. In addition, the significantly lower price, compared to natural wood, has finally won over buyers.

An increasing number of people want to surround themselves with natural materials, but at the same time take advantage of modern technologies: reliability, durability, and a constantly well-groomed appearance.

Various types of matrices

There are several common species molds for making artificial stone. The forms differ in appearance, material, properties, but they are united general principle creating the final product.

The inner surface of any matrix is ​​made in the form individual texture. It could be wood, stone structure, marble veining and so on.

The gypsum or cement mixture is poured into the mold. Upon completion of the process, when the solution has hardened, matrix texture reflected on the surface of the artificial stone. In essence, the technology is striking in its simplicity, but it has its own subtleties and nuances.

Molds for gypsum stone, depending on the material used, are divided into the following types:

• Wooden formwork.
• Plastic.
• Silicone matrices.
• Made from polyurethane.

Formworks for manufacturing must be very strong and wear-resistant. Matrices must be abrasion-resistant and insensitive to aggressive chemical elements that are present in binder solution.

Depending on the material, the matrices are designed for different numbers of pours and different depths of pouring.

The comparative characteristics of the matrices look like this:

• The silicone matrix can withstand up to two thousand fills with relief of any depth.
• Polyurethane is designed for up to three thousand fills. The depth of the relief is unlimited.
• A wooden pallet can withstand no more than twenty pours and is designed for a flat façade.

Description of silicone molds

Silicone is synthetic material with universal properties. It is produced by dissolving quartz powder in nitric acid. Silicone is, in principle, harmless and non-toxic. Does not interact with acids and alkalis. Silicone products are elastic, durable and have good strength.

The elasticity of silicone molds allows you to quickly and without damage remove the frozen product from the matrix. When producing silicone molds, they try to use silicone with maximum viscosity.

Silicone molds have a number of advantages:

• High elasticity.
• Ideal shape for gypsum mortar.
• Good tensile strength.
• Relatively cheap material if made independently.

In front of everyone positive qualities Silicone still has some disadvantages:

• Chemical resistance is not very good.
• When making the mold, air bubbles may appear. Because of this, defects on the surface of the matrix are possible.

Features of the polyurethane version

Polyurethane is a polymer material. It consists of an isocyanate and a polyol. If these components are mixed in different proportions, the resulting material may have different properties. It can be soft or hard, flexible or foam. Therefore, polyurethane is even more versatile than silicone.

For gypsum mortar a matrix will do made of soft polyurethane. In the case of cement mortar, a form that is rigid in structure is required. Compared to silicone, liquid polyurethane is more fluid. Based on the properties of polyurethane, it is considered the most successful and inexpensive option. With its help, they create durable and elastic forms.

The following advantages of a polyurethane matrix can be highlighted:

• Stability.
• Chemical resistance to acids and solvents.
• Durability and excellent retention of original shape.
• Good abrasion resistance.
• Low inertia.

Properties of wooden formworks

Creating a form for decorative stone made from wood with your own hands is considered not the most best idea. The wooden matrix is ​​assembled from planks and boards. This material creates some form on a wooden tabletop. Using slats between the walls of the frame make cells. The bottom of the mold is fibreboard or boards. The result is a primitive, rough form without fine texture or shaped geometry.

Texture in this form is created either by using a raised backing or by using a cracked board with imperfections on the bottom.

There are few advantages, but they are there:

• The cost is relatively low.
• Fast and easy production.

The disadvantage of wooden “matrices” is:

• Fragility.
• Weak tightness.
• Only simple geometric shapes.

A little about plastic

Plastic matrices can only be manufactured under production conditions. These forms cannot be made independently at home.

A distinctive feature of plastic matrices is their rigidity and fragility. Their use involves increased caution and accuracy. These molds are much cheaper than silicone or polyurethane models. The main area of ​​use of plastic molds is limited to paving slabs.

An interesting fact is that polyurethane is used in the manufacture of plastic. The production itself involves hot casting and pressing on special factory machines.

Making your own mold

The procedure for making artificial stone involves holding the liquid solution in the chosen form until it dries and hardens completely. First you need to create a form for the matrix. For silicone and polyurethane, an almost identical approach is used.

To make the matrix you will need:

1. Table. Flat and even, located in a closed, warm room. The size of the table must be at least 1×1 meter.
2. Box for filling. It houses the master model. The box is smooth plywood. It is best if it is laminated or varnished. Plywood size is future form plus the thickness of the plywood on each edge. Confirmats secure the sides to the bottom and to each other. The height of the sides is about 5 centimeters.
3. Suitable stones are master models. Smooth and even on one side.
4. Acrylic sealant.
5. Super glue. You can use a universal PVA type.
6. Construction hairdryer.

Stages of creating matrices

As an example of the production of artificial stone, a description of the independent production of a polyurethane mold is given.

The preliminary stage is the preparation of the master model. First of all, the sample is well cleaned of dirt and dust and dried. Moisture is not allowed. The model and the inner surface of the filling box are treated with a release agent. The lubricant is applied evenly and accurately. The lubricant should not be in a very thick layer, so as not to hide the texture and texture of the stones. After lubrication, the sample should dry for about ten minutes.

Then the model needs to be warmed up. The model is warmed up with a hair dryer. This is necessary so that the paraffin release agent melts a little and fills the micropores. The excess separator flows off, and a thin layer is formed on the stone, guaranteeing an exact copy of the texture.

The model is assembled by screwing the sides and leveling them. The mold must be sealed along the entire perimeter to avoid loss of molding material.

The components of the molding sand are weighed according to their proportions. Before weighing and mixing the ingredients, make sure they are at room temperature. If the material was stored outdoors in the cold or transported, it may take a day to reach room temperature.

It is believed that the room temperature when pouring should be 20-25 °C with a humidity of 40-50%. For mixing you will need dry buckets or glasses. They must be clean and of the same volume. Equal quantities by weight or volume of polyol and isocyanate are placed in buckets. Using a conventional drill at medium speed, mix the mixture for two to four minutes. The rotation of the blade or paddle should be counterclockwise. In this case, excess air bubbles will not be captured.

After thoroughly mixing the components, you have approximately ten to fifteen minutes to pour the liquid mass onto the master model. During this time, the compound will go from a liquid to a gel state.

Filling should be done carefully from one corner. Then the mixture will fill the entire space without gaps. The formwork, filled to the very edges, remains undisturbed until the liquid completely hardens.

At the final stage, the formwork is stripped and the finished product is removed from the molds. After the material has hardened, it is carefully removed. Stripping can be done after twenty to twenty-four hours. After extraction, excess sagging is cut off. It must be remembered that for a few more days the form will gain strength. Only after this the matrix can be used.

Artificial stone based on gypsum

One part of water is mixed with one and a half parts of gypsum and mixed thoroughly with a mixer.

To prevent the solution from immediately hardening, add lemon acid, diluted in warm water. The estimated proportion is 0.7 grams per 1 kilogram of dry gypsum. Then fine sand is gradually added to the mixture. The size of sand grains is up to one millimeter. Approximately one hundred grams of sand per kilogram of dry gypsum. After this, universal PVA glue is added. It takes on the role of a plasticizer.

The mixture is constantly stirred, and at this time dye is gradually added. Until the solution has acquired the required color and shade. After treating the inside of the matrix with a special lubricant, the solution fills the entire mold to the very edges. The form is shaken several times. Using a spatula, the mixture is compacted and distributed evenly.

After half an hour, the solution should begin to set. In this case, the matrix is ​​covered with plywood and turned over. After complete drying, the finished stones can be removed. To protect the product, it can be coated with colorless matte varnish. The first forms and final products are not always perfect. Everything comes with time. In order for the final product to be beautiful and effective, you need to be patient and gain a little experience.

But in the end, making your own facing tiles brings indescribable satisfaction and good mood from the results of labor. With significant cost savings.

Artificial stone made from casting molds is suitable for exterior cladding, interior elements, borders, tiles, and fences. Manufacturing stone for a specific purpose ensures that the created material will meet quality requirements and provide a consistent appearance. Polyurethane molds for the production of artificial stone allow you to reproduce almost any structure.

Polyurethane mold for artificial stone

Polyurethane molds are the basis of the production process for creating a stone structure. This is the most expensive piece of tooling and equipment. The high quality of the matrix allows you to turn the poured solution into a durable product.

There are three main types of molds.

Plastic molds are a cheap type of matrix. The material is extremely difficult to process. Short term service - about 50 casting cycles, which requires monthly updates.

Flexible forms - silicone compounds and resin elastic materials. The disadvantage is the increase in the number of bubbles scattered over the entire surface, and the difficulty in painting it due to the fat content of silicones, in contrast to polyurethane resins.

Polyurethane forms. Durability up to 40 cycles and high levels shrinkage.

Polyurethane molds are preferred for the stone casting process. When properly maintained, matrices can last for years and produce thousands of elements.

Tools and materials for preparation

For high-quality templates that can accurately convey the texture of natural materials, injection molded polyurethane is used. This unique material is resistant to wear, corrosion and flexibility, and can withstand high mechanical loads.

Polyurethane molds are made by cold polymerization, a solution to form two-component polyurethane compounds. Despite the simplicity of the technology, creating a reliable model requires a lot of experience.

To obtain a polyurethane mold with your own hands, you need:

• samples made of artificial or natural stone;
• two-component polyurethane compound;
• sanitary silicone;
• plywood, MDF or chipboard;
• self-tapping screws;
• liter bucket;
• putty knife.

To make frames, you need to prepare a smooth section of MDF or particle board according to the size and pattern of the side wall elements. A texture pattern is copied onto the surface of the plate by mounting plumbing silicone. The distance from the sample to the side walls must be at least one centimeter. Next, the assembled formwork is sealed with a silicone frame and filled with mortar.

Polyurethane compound

The main consideration when choosing a mold material for casting is the presence of fillers in the compound: to reduce cost, change strength, weight or appearance castings to make the matrix structure more workable before or after solidification. The "A" portion of the compound, of most two-part polyurethane resins, comes with a certain amount of filler already included.

A high quality line of two-component liquid rubbers is available commercially that can be poured, spread or sprayed during the template making process at room temperature.

Polyurethane compound is two solutions based on different polyurethanes. The mixture of combined components solidifies at room temperature.

The material is designed specifically for the manufacture of molds for casting artificial stone, since, thanks to its plasticity, it can easily repeat any complex pattern with maximum accuracy. Due to its liquid state, the raw material can be easily measured, mixed and prepared for casting.

The solution has a fast hardening time, which allows you to work with the matrix a few hours after production, but the time for complete stabilization is about 12 hours.

The presence of filler in the compound will result in exothermic heat buildup, which slows down the curing reaction and reduces the shrinkage rate. When working with cast polyurethane, it is recommended that when using a significant amount of filler, the percentage of added catalyst is increased from the usual 1% to 2% (even up to 4% when mixing small volumes).

Polyurethane mold making process

Creating an artificial stone begins with making the right template. A large number of castings can be made from one high-quality matrix. With a durable mold, you can reproduce almost any type of texture, and create uniform tiles or sections, which is important when installing large surfaces.

Two types of molding processes can be used: open and closed casting. Flexible molds can be produced by pouring. In this case, their lower surface will be smooth and flat, but due to the deformation of the side walls caused by the weight of the poured solution, the matrices must be significantly increased in thickness. This leads to significant consumption of the compound and costs for the manufacturing process of the casting structure.

Block mold production is the fastest and the easy way, but requires more molding material.

Production stages

The process consists of several stages:

1. Designing a model - a prototype made of stone or tile that needs to be recreated, where all the other sections will be located.
2. Creating a casting box - a frame with walls around the model; you can use plywood.
3. The molding compound is mixed according to the manufacturer's instructions.
4. Place the prototype in the die by pouring the material into the corner of the mold so that the solution flows gently through the prototype as this will reduce the formation of bubbles.

After the molding material has hardened, disassemble the matrix and carefully remove the resulting model from the prototype. Open casting is used mainly for flat objects with slight differences in relief. A simple molding method, especially suitable for beginners.

The sample is rigidly fixed in a sealed polyurethane form, with a distance between the patterns usually exceeding 2 cm. The finished mixture is applied with a soft brush for precise relief coating and removal of air microbubbles. The mixture is then poured to ensure a minimum mold thickness of 6 to 10 mm. The main advantages of open pouring are simplicity and the ability to visually control the air pocket when using transparent polyurethane grades.

Advantages of forms

The manufactured polyurethane molds have increased ductility and strength, and thanks to special fillers, they have high abrasion resistance. Such frames allow you to create stones from silicone, wax, concrete, gypsum, low-metal mortars, epoxy or polyester resins.

Advantages of polyurethane molded products:

• Products obtained from polyurethane molds are characterized by high degree imitation of natural surfaces.
• It is possible to use materials that perfectly reproduce the relief of a natural surface.
• Thanks to the inner surface of the mold, you can get a variety of product colors and create effects of spraying, blurring, and overlaying shades.
• The resulting decorative stone has a clearly defined geometry and low weight, which ensures the implementation of the design and easy installation.
• Molded elements do not require any additional finishing.

Designs for artificial stone made from injection molded polyurethane, compared to the strength of a plastic mold, are productive for 2 years, and have:

• Good operating characteristics.
• Light viscosity and fluidity.
• Low shrinkage.
• No deformation.
• High hardness.
• Heat resistance.
• Resistant to acids and alkalis.
• Aging resistance.

Polyurethane forms allow you to create a huge range of models: decorative wall from brickwork, lined stone or brick, modern 3D panels, large-format panels made of decorative stone, ultra-thin and flexible stone wallpaper, luxury paving slabs, as well as elements of architectural decor.

Just a few years ago, the concept of “artificial stone” was unknown to few people in Russia. But few people have heard about the use of finishing materials made using this technology.

But recently, artificial stone products are increasingly conquering our construction market. Thanks to the simplicity of manufacturing technology, low initial investment, high profitability and the ability to simulate various natural materials, its production is rapidly developing. Moreover, artificial stone has become widely used not only in the design of facades, but also in the creation of interiors.

In the production of artificial stone, the molds for its production are of great importance.

The quality of artificial stone is mainly determined by the material from which the molds for its production are made, which must meet the following requirements:

• Mechanical strength. The form must have good strength and extensibility, not break or tear when significant forces are applied to it, and quickly restore its geometric contours.
• Abrasion resistance. The form should convey the smallest relief details of the stone surface with maximum detail.
• Chemical resistance. The solution for making artificial stone contains alkaline materials, which can lead to the destruction of forms.

Currently there are several types forms used in the production of artificial stone:

• Hard(collapsible or solid). Made from metal or plastic. They have significant shortcomings, limiting their use:
  • blurred relief of finished products;
  • design complexity when casting volumetric products;
  • possibility of damage to finished products and molds.
• Semi-rigid(solid or collapsible). For their production, cheap plastic and polyurethane, hot-curing rubber are used. In addition to the disadvantages characteristic of rigid forms, they have additional flaws:
  • the presence of an additional rigid body;
  • high consumption of raw material for their production.
• Elastic(solid or collapsible). These are the most applicable types of molds and the following types of mold materials are used for their manufacture:
  • formoplasts;
  • plastic;
  • silicone;
  • polyurethane;
  • rubber.

Formoplast- the most primitive form material, used since the mid-20th century. It was widely used before the advent of quality elastomers, but its time has long passed. Used in the artisanal production of low-quality artificial stone.

From advantages one can note the low cost of equipment and raw materials, and shortcomings relate:

• significant shrinkage of the material during cooling, which leads to loss of geometric dimensions;
• softness of the mold, leading to deformation of the sides of the product in the form of “bubbling”;
• low abrasive resistance, which makes it impossible to use them when working with concrete;
• high labor intensity of processing raw materials;
• harmful to health;
• low durability, which requires monthly updating of forms.

Due to its disadvantages, plastic is rarely used for making molds:

• low durability;
• the inability to convey all the nuances of texture;
• the difficulty of making it yourself;
• inconvenience of operation (gypsum products often stick to forms, which leads to their damage when removed).

The advantages include its fairly moderate cost.

Silicone applies to enough large group elastomers for various purposes, differing significantly in their characteristics. It is popular with our mold manufacturers, which are easily made by hand. To do this, it is enough to prepare the base, silicone solution and one ready product as a template.

Their advantages:

• ideal for plaster casting;
• possibility of self-production.

High-quality silicone molds are produced only abroad and they are very expensive. Their main disadvantages:

• low chemical resistance to alkaline materials;
• the appearance of bubbles on the sides of decorative products;
• difficulty in painting finished products;
• significant price.

Polyurethane is the most common material for the manufacture of elastic injection molds, which are ideal for cement vibration casting. They are characterized by the following advantages:

• used when working with gypsum and concrete;
• high abrasive resistance;
• easily separated from the hardened surface of the product;
• accurately convey the surface topography;
• low price.

At the same time, polyurethane forms have a number of shortcomings:

• presence of air bubbles on the surface of the mold;
• the quality of the form largely depends on the quality of the source material;
• when using cheap polyurethane, concrete causes deformation of the forms;
• dependence on the human factor (failure to comply with technology in the manufacture of molds).

Rubber is increasingly used in the manufacture of molds using hot polymerization under pressure. The molds are made automatically using high-quality equipment, which ensures the stability of their quality. Their advantages include:

• high abrasive resistance;
• duration of operation;
• maintaining geometric dimensions throughout the entire service life;
• the rubber surface of the mold holds coloring pigments well on the surface, which makes it possible to use all methods of painting artificial stone;
• the absence of air bubbles inside and on the surface of the mold guarantees high quality products;
• almost perfect reproduction of the texture of natural stone;
• low cost.

TO shortcomings include the high cost of equipment for the production of molds and the need to train operating personnel.

Brief description and cost of forms

Formoplast. Such forms can withstand 450 - 1000 castings, the relief is repeated by 95%, are easily processed (8 - 10 times), and are used for filling with materials with temperatures up to 70 0 C. Their cost ranges from 550 to 1200 rubles / m 2.

Plastic. The most inexpensive material, used for the manufacture of tiles with a primitive imitation of stone, can withstand 300 - 850 castings with a material temperature of up to 70 0 C. Their cost ranges from 350 to 1300 rubles / m 2.

Silicone. The molds harden at room temperature, have average strength, and can withstand up to 2000 castings over a wide range of temperatures of the material being poured. Their cost ranges from 1650 to 4300 rubles/m2.

Polyurethane. They require strict adherence to the instructions for mixing the components, otherwise the strength and durability of the molds will sharply decrease. They harden at room temperature and last up to 4000 castings. Due to adhesion to poured materials require a lot of lubrication. Their cost ranges from 2850 to 5300 rubles/m2.

Rubber. The most common material for molds that accurately reproduce all surface details and can withstand up to 6,000 castings in compliance with the geometric dimensions of the products. They are used in a wide temperature range from -90 0 C to +300 0 C. Their cost ranges from 700 to 1600 rubles/m 2.

Price artificial stone on the construction market is quite high. A self-made mold can significantly reduce these costs.

For making simple shapes with even geometric sizes, you can use simple boards or plywood, fastening them together.

In order to make a beautiful artificial stone, it is best to make a mold from silicone. To do this, you need to carefully prepare several original templates. The natural stones on which the forms are created are thoroughly washed and dried. To prevent silicone from sticking, they are coated with wax or paraffin.

Cooking wood container of the required size and coat it with plasticine. A natural stone prepared as a template is laid on it.

Silicone It is made from a catalyst and a hardener, which are thoroughly mixed, observing the proportions specified in the instructions. After leaving for 30 minutes, the molding silicone is slowly poured over the template. It should spread well around it without forming air cavities.

Complete hardening forms are carried out within 1 - 2 days in a dark place, protected from moisture. Then the wooden container is carefully disassembled, the template (natural stone) is removed and that’s it - the form is ready for use.

Artificial stone manufacturing technology

Most widespread technology making artificial stone from cement, fine sand and water. To do this, cement and sand in a ratio of 3:1 are thoroughly mixed until a homogeneous mixture is obtained. The dye is added to the water, with the help of which the resulting cement-sand mixture is stirred until the consistency of sour cream.

The pre-made form is filled with the resulting solution. To compact the solution form within one minute necessary lightly tap and shake. After 12 hours, the resulting artificial stone is removed from the mold and left for two weeks to dry and gain the necessary strength.

After extraction The stone form is thoroughly washed with soapy water and becomes ready for pouring the next artificial stone.

Decorating walls with artificial stone is fashionable, prestigious and aesthetically pleasing. You can't argue with this statement. This material is too good to refuse to use it, but too expensive to choose it without hesitation.

You can make a batch of material for a home decorative panel with your own hands. Fortunately, our users are ready to share their work in this area completely free of charge. There are several technological solutions that can be used at home with equal success. And today we will look at one of them: one that is based on the use of homemade silicone molds.

From the article you will learn:

• What materials are needed to make silicone molds for decorative artificial stone.
• All about making silicone molds yourself.
• Everything about pouring technology and the composition of mixtures for making artificial stone.

Why silicone

In fact, the forms (matrices) intended for the manufacture of artificial stone at home are made from various materials, natural and synthetic (wood, rubber, silicone, polyurethane, etc.). Each material has its own advantages and disadvantages:

• rubber molds - products are durable and easy to handle, but they are very difficult to make at home;
• polyurethane forms are elastic (which is their undeniable advantage), but difficult to manufacture;
• Silicone molds are quite durable, elastic and easy to make.

dronduletus User FORUMHOUSE

I mainly made the molds from sealant (silicone). It is better: this form conveys the relief better, and it is easier to remove the finished casting from it. If you cast a stone from plaster, such a mold can withstand up to 200 castings.

Samples for making molds

The first thing you will need to make silicone molds is samples of stones that you plan to produce at home. It is recommended to use several samples of the same type (master forms) at once, which differ in relief and texture.

This greatly enhances the richness of shapes and textures. The number of initial samples depends on your wishes and the area of ​​the formwork that will be used to make the form. One form can be designed for one or ten different cells - it all depends on your needs and scope. You can start your “experiments” by making a mold for pouring one stone. To produce stones of the same type, it is better to make several identical shapes.

dronduletus

It is better to make 3-4 molds for 1 type of stone. This way it’s faster to pour stones, and the molds will last longer.

Initial samples are purchased on the construction market; they are widely represented in Moscow and other cities and regions.

Master molds for matrix production must have the highest quality surface possible. The surface of the samples should not be full of all kinds of shells, open pores concrete and other defects.

Formwork design for the mold

Having prepared several suitable stones as samples, you can begin to create the formwork. Considering that the chemical compounds that make up molding silicone (namely, it is best to cast a matrix for artificial stone from it) are quite strong reagents, it is very important to choose the right material for making formwork. To achieve our goals, sheet material with a smooth and chemically neutral surface is ideal: plywood, plastic, etc.

dronduletus

Silicone is a chemically active material. It easily corrodes some surfaces and quickly sticks to them. For formwork it is better to use PVC panels or some kind of plastic. Possibly plexiglass. Personally, I made the edge of the formwork from mayonnaise buckets.

To make formwork, we need a chemically neutral base and four smooth walls (made of wooden slats).

The height of the slats should be selected so that the layer of poured silicone is at least 1–2 cm above the top point of the master mold.

The thicker the bottom of the silicone mold, the longer it will last. But making molds that are too thick results in wasted silicone. Therefore, when deciding on this parameter, everyone is looking for a “golden mean” for themselves.

Formwork assembly

Before assembling the formwork, the prepared master forms should be glued to the surface of the base. The distance between adjacent samples, as well as between samples and the walls of the formwork, must be at least 1 cm.

Ideally, the molds should be glued to the base of the matrix with hot glue (using a special gun).

If such equipment is not available, you can use regular silicone sealant. The sealant is applied to the underside of the master mold along its entire perimeter, after which the original sample is glued to the surface of the base.

It is very important to apply sealant (adhesive) along the entire perimeter. This will help avoid the formation of gaps between the master molds and the base. If any gaps remain, silicone will easily fill them. As a result, the finished silicone mold cannot be removed from the formwork.

Excess glue that is squeezed out beyond the outer contour of the master mold should be removed with a regular breadboard tool.

Once again making sure that there are no gaps left between the stones and the base, you can install the formwork walls. The formwork is attached to the base with self-tapping screws (it is better to drill holes for the self-tapping screws in advance). It is advisable to glue sealant tape between the walls of the formwork and the base, as well as on the ends of the walls.

This will reliably protect the formwork from silicone leaks.

Applying a separator

A separator is a composition that is applied to the inner surface of the formwork, as well as to the samples used. The separator prevents the silicone from sticking to the surface, so the finished form can be easily removed from the formwork after hardening.

It is customary to use a soap solution as a separator. Laundry or toilet soap is diluted in a container until a thick foam is obtained (the consistency is approximately like shaving foam), after which paint brush carefully applied to the surface of stones and formwork.

Soap suds have proven to be quite effective separators. But anyone good remedy there is always a worthy alternative. If you don’t mind the additional costs, then you can purchase anti-adhesive aerosol lubricant on the construction market. Here's what one of our users recommends using.

dronduletus

Oils are absorbed and evaporated, so the silicone can stick. Conclusion: you need to separate with grease. Before coming to my results, I read a lot on the Internet and tried a bunch of options in practice.

Silicone filling

After the formwork has dried, you can begin pouring silicone. For work, it is recommended to use two-component liquid silicone, which is designed specifically for the manufacture of decorative forms.

Silicone (compound + hardener) is diluted in accordance with the manufacturer’s recommendations and poured into the formwork in a thin stream.

Before pouring, the formwork should be aligned exactly to the horizontal level.

After waiting the time required for the silicone to harden (the time is indicated by the solution manufacturer), you can remove the form from the formwork. If the separator was applied in a continuous layer, the silicone mold will easily move away from the surface of the formwork and decorative stone samples.

Silicone molds are durable: the finished matrix can withstand 200 pours of gypsum and 50 pours of concrete mixtures.

Making stone

In most cases, cement or gypsum mortar is used to make artificial stone. For finishing the façade, a stone based on sand and cement is best suited (such material is better protected from the harmful effects of atmospheric factors). Gypsum stone is most often used when it is necessary to decorate the interior. It is these principles that should be followed by those who do not yet have enough experience in the manufacture of artificial stone.

Dronduietus

Regarding gypsum: many do not recommend using gypsum stone for facade work. But it is mainly not recommended by those involved in the production of stone: it is more profitable, more expensive and easier to sell concrete; and plaster needs high-quality protection. Gypsum tiles need to be strengthened with various additives, so few people decide to experiment. Although there are people whose plaster sculptures and stucco moldings stand on the street for 10 years, and nothing happens to the material.

Pouring technology

When pouring artificial stone into silicone molds, one thing must be taken into account: important point: for the purpose of high-quality decoration of products, it is best to apply the outer layer of color (paint) not to the stone itself, but to the inner surface of the silicone mold. Therefore, the mold is filled in 3 stages.

Stage one– coloring the form. The inner surface of the mold is painted with diluted dye. When pouring concrete, a dye for cement mortars is used, when pouring gypsum, a dye for gypsum tiles. Coloring is carried out randomly (without a specific “artistic intent”), which allows you to obtain a completely natural texture on the front surface of the stone.

Painting should be done immediately before pouring the building mixture (so that the color does not have time to dry).

Stage two– pouring the starting mixture. A small amount of the mixture containing the dye is poured into the mold and spread over its internal surfaces with a spatula.

The composition of the cement mixture differs from conventional mortar in the ratio of components: one part cement (M400...M500) and three parts sand (a little less sand can be used). The dye is diluted at the rate of: 2...3% by weight of solid components (sand and cement).

The composition of the gypsum mixture: gypsum (grade G-5 and higher), food grade citric acid, which slows down the setting of gypsum (0.3% by weight of gypsum), dye (5...6% by weight of gypsum) and water.

The gypsum and cement mixture are diluted with water to a consistency that resembles liquid sour cream.

Stage three– pouring the base mixture. The base mixture contains all the components of the starting composition (with the exception of dyes).

The second and third stages can be combined by pouring the base mixture (with dye) in one go.

It is preferable to pour the base mixture on a vibrating table. Without vibration, the quality of the tile may suffer slightly, as air bubbles may remain in the internal structure of the stone.

The stones are removed from the mold after hardening. Cement stone can be removed after 12 hours, gypsum stone - after 20...30 minutes. After removing the stones, the mold should be washed thoroughly (this will extend its service life).

– this is a rather extensive topic that is discussed on the pages of our portal. From it you can glean information about additives, additives and plasticizers, as well as various filling technologies that our users successfully use in practice. We also suggest that you read an interesting article on how (that is, without using pouring forms). A video about decorating a wooden facade with natural stone will tell you about installation rules that apply to both natural and artificial decorative elements.

A mold for self-production of artificial stone can be purchased at a construction supermarket. But if you want a product with non-standard form, then you need to learn how to make forms.

It is impossible to make high-quality artificial stone without molds into which a solution of a certain composition must be poured.

By and large, this is the simplest question at the moment. Why? Yes, only for the reason that such products are sold in any construction supermarket. The only problem is that not everyone has such a supermarket nearby or it’s not always easy to get to it.

But, in in this case, the problem is also not solved, because to obtain materials for the production of the mold, if you want to make it yourself, you will also have to look for a similar supermarket.

That is, there is only one question - buy a mold or make it yourself. Let’s say right away that independent production is in no way cheaper, well, maybe by a penny, and then only if you make several products at once. Then why, as they say, bother?

This is a matter of honor for a summer resident who is ready for complete independence, or simply decided to make stones in the future of exactly the shape that is most interesting to him (after all, in the supermarket all the products are standard).

Self-production is in no way cheaper, well, maybe a penny, and then only if you make several forms at once

A finished model can give you at most a few views of the finished product during production. There are even dozens of forms you can make yourself, depending on your imagination and the initial materials for creating the layout.

Wooden forms

Wooden models are not the most successful example, but we should also point to it, because stone production takes place with their help. How does the production of a model for facing material take place?

Everything here is quite simple - to create a wooden model, several old boards are selected, preferably with as many defects as possible, as well as even slats. The bottom of the model is made from boards, and the side sides are made from slats. We take old and broken boards so that the upper, decorative part of the stone has a unique shape, with a unique pattern.

The sides must be even, as well as the additional partitions inside the form, so that we can maintain the same distance between the stones during laying. Although, if the stone is produced for a chaotic pattern, you can do everything according to your own requirements, the shape can even be non-standardly curved, the partitions can draw the most intricate patterns and shapes.

The model is knocked down with nails, well strengthened and compacted so that the future solution does not disappear from it. In terms of size, the decision is up to you, since we cannot decide for each summer resident what characteristics the material needs.

Then everything goes according to technology - preparing the solution, pigment, reinforcement, coating the mold or laying polyethylene, pouring with stirring or tamping, drying the solution and obtaining the finished material.

Claim practicality or high quality We simply cannot use such a model for stone production. No, of course, we have experience working with such structures, but not the best, and even more so, today there are more reliable technologies that provide decent results.

Silicone stone molds

Making such a design will take you some time, plus there will be the inconvenience of traveling to the supermarket to purchase consumables, as well as some costs. But as a result, you will get a truly exclusive stone that no one else has, if, of course, you can cope with the production process the first time.

The mold for artificial stone may not work out the first time, so be careful about the process

Selecting samples for making molds

Perhaps the simplest stage of the process is when you need to determine what type and size of material you want to receive subsequently. To select a sample, you can take a natural sample, its fragments, or do something yourself, breaking stones or cutting and grinding their edges.

Making a mold for casting the model

Here we will need experience in the production of wooden boxes and boxes, which is generally very simple. As a basis, you can take a piece of old furniture, a square or rectangular sheet of laminated chipboard, for example.

Next, you need to nail the sides to the sheet of the same height as the thickness you plan to make the model. Everything should be quite tight and secure; you can even coat all parts with glue, and only then twist it with screws or knock it down with nails.

Laying stone into shape

We carefully lay out the samples that we found at the dacha or made using a tool. Be sure to maintain a certain distance between them, a few centimeters. When laying the stone on the bottom of the box, coat the joints with plasticine so that liquid silicone does not flow under the samples.

When preparing the stone, you should understand that one side of it must be flat; this is necessary for convenient placement in the box, as well as in order to obtain as a result a high-quality material for work, one side of which will be able to adhere to the surface being finished.

Preparation of silicone for mold production

There is nothing complicated in preparing the material - you just need to work according to the instructions, add the hardener and catalyst in the required proportions, mix everything thoroughly using an electric mixer.

After preparing the silicone, let it sit for about half an hour and proceed to the next step.

Filling the form

The stones are checked for correct installation in the box, coated with grease or other lubricant, and the silicone is poured into the box with the stones. During this process, you should constantly tamp the silicone so that it lays down in an even layer. This will also prevent the formation of unnecessary voids in the future form. Pour silicone until it covers the tallest stone in the box by about 5 cm.

Now the molds with silicone must be placed in a dark and dry place and allowed to dry thoroughly. In some cases, the product is ready within 36-48 hours, but sometimes you have to wait a week. Everything here depends on the material and conditions of production and drying.

At the end of the drying period, the side sides of the box are removed, and finished form carefully separated from the sample stones. Now it is completely ready for use for the production of material. published

If you have any questions on this topic, ask them to the experts and readers of our project.