Features of storage of self-solidifying clays. Rules for storing polymer clay What is the difference between Fimo Soft, Classic and Effect plastic

Many girls who want to diversify their gray everyday life and find a hobby for themselves - a way to relax and escape from everyday problems, choose modeling, but do not think about what is the composition of polymer clay. However, over time, everyone comes to this question.

Compound

Mostly the material consists of a specially made plasticizer that makes the clay so pliable. In addition, the product contains ordinary PVC, which, like edible gelatin, can absorb a large amount of a substance during the heating process.

When these two elements - PVC and a plasticizer are heated, the process of thickening is carried out: the plasticizers in the clay absorb small particles of powder, then gradually move closer to each other, and, having visually indefinite and irregular shapes with dents and, conversely, tubercles, adhere tightly to each other. It should be remembered that the more plasticizer was originally in the original composition of the clay, the more plastic and softer the final product will be.
The substance, which was obtained in the final result in the heating process, is referred to as "plasticized PVC". On the industrial enterprises this material is used to make household items, various medical instruments, as well as PVC windows.
Also, a variety of pigments that differ in quality and color can be included in the composition of polymer clay. Well, as fillers in the composition of plastic can include substances such as, for example, chalk. Stabilizers may also be present in the clay, which prevent the plastic from gelatinizing during normal storage at room temperature. Plastic hardens already at sixty degrees, however, the stabilizers included in its composition significantly slow down this process.

Thanks to which polymer clay is easily molded

As mentioned earlier, the plasticity of polymer clay is achieved by adding a certain amount of plasticizers to it, which are included in the finished material. That is why soft and not very polymer clay can be purchased at your choice, and everyone can acquire their own type of material for making earrings, dolls, sculptures and so on.

Does polymer clay have a shelf life

Manufacturers who make polymer clay claim that it has no shelf life when stored properly. The only thing that can happen to your plastic is its hardening. That is why many leading manufacturers of polymer clay produce special softeners that help to bring the material into the desired form.
However, on some packages with Russian translation, you can find a specific expiration date. What could this mean and where is the catch? The thing is that some Russian suppliers they incorrectly translate the information, or are illiterate in this matter, and so the expiration date of the hygienic conclusion appears on the package.
A slightly different story with the Russian polymer clay Sonnet. It has a shelf life, but this does not mean that the material of this manufacturer is of poor quality.

Is polymer clay harmful to health?

Despite the fact that polymer clay is practically not harmful to health, it is still necessary to adhere to safety rules when working with it. This rule is especially important for children's creativity.
The composition of polymer clay for children's creativity has been allowed from the age of 3 and must be thoroughly tested.

Polymer clay manufacturers

Currently there is great amount polymer material for sculpting, and here are just a few of them.

FIMO- one of the most common plastics in stores until 2010. Back in the distant thirties, a master from Germany developed this amazing material, and in 1964 he sold his patent to another company. Fimo plastic was the most popular polymer clay on the world market until 2010, when it was renamed and it was released under the STAEDTLER brand. The manufacturer produces different kinds clays with different weight categories and color palettes.

CERNIT Is another leading manufacturer of polymer clay. The brand also had German roots, but relatively recently it was bought by a Belgian company called DARWI. Plastic is famous for its unusual properties - it seems to be very hard to the touch, but as soon as it feels the warmth of human hands, it, like an affectionate kitten, instantly becomes soft and pliable.

SONNET. Separately, it is worth highlighting and Russian manufacturer polymer clay, since we are talking about domestic production.
This is Russian plastic, which is produced in St. Petersburg by a special plant, mainly engaged in the production of paints for artists. Currently, the color range of this manufacturer includes more than 20 classic colors, 15 colors with mother-of-pearl, as well as 5 colors glowing in the dark. The material itself is quite hard and requires some effort in order to soften the plastic. Clay makes good products, in addition, it does not get your hands dirty.

We are often asked the question of how to properly store polymer clay? In this article we will try to answer it in as much detail as possible.

First, let's decide on the type of plastic: baked or air-dried.

Temperature

To store polymer clay, no special conditions are required - room temperature is quite enough, it can be stored in a cool place. Wherein baked clay easily tolerates negative temperatures (it is even recommended to store ready-made kane in the cold), while drying out When exposed to air, plastic contains water and freezing can adversely affect the plasticity and uniformity of the clay.

Where to store

Choose a storage location that is not exposed to direct sunlight - this plastic can become fragile and fade slightly. It is also necessary that this place be away from radiators and heating devices. Excessive heat can harden clay and become unusable.

What to store

Unopened original packaging can be stored as is for a long time. Opened packs of baked and self-hardening plastics are stored differently.

Baked the clay is not harmful to being in the open air, but still it is not worth keeping it that way for a long time. Firstly, the clay can become dusty, small villi cannot stick to it, which, as a result, will simply ruin appearance products. Secondly, the plasticizer does evaporate. Very, very slow. Therefore, it is better to store by wrapping the clay with foil, cling film or wax paper.

Why is it so? The plasticizer in the baked clay can react with some polymeric substances (polystyrene, plastic, some polyethylenes). For this reason, do not allow wet clay to come into contact with plastic surfaces. For the same reason, baked and unbaked plastic should not come into contact - the plasticizer will react with the finished product.

Also, don't wrap raw polymer clay in paper. It absorbs the plasticizer well and from this plastic it becomes more rigid, it can begin to crumble if it remains in this state for a long time. An exception is waxed paper, as it is already soaked and cannot absorb any more.

Self-hardening clay, unlike baked clay, is afraid of contact with air, since the water contained in it evaporates quickly enough. Therefore, it is imperative to exclude the access of air to the plastic. To do this, you can tightly wrap a piece with cling film, squeezing out all the air bubbles. Some also recommend putting the resulting briquette in a zip bag or tightly closing container along with a damp cloth. This container will retain moisture to prevent drying.

Where to begin?

Let's start with the definition.

What is polymer clay?

Polymer clay there are two types: baked and air-hardening (self-hardening).
In this article, we'll take a look at baked polymer clay.

Polymer clay or, as it is often called, plastic, modeling mass is a synthetic material that hardens when baked in a kitchen oven at a relatively low temperature (110 ° C or 130 ° C, depending on the brand of polymer clay).

What happens to polymer clay?

Baked polymer clay is a non-toxic, fairly soft material that does not harden in air and remains plastic before baking. During baking, the plasticizer burns out (evaporates), which leads to the hardening of the material, which in its properties will be identical to plastic (plastic). After firing (baking), polymer clay does not lose its shape and can be further processed: polished, painted acrylic paints, varnished, etc.

What can be done?

Polymer clay is ideal for making jewelry, dolls, miniatures, sculptures, ornaments, small parts for modeling ... It is suitable for artists, craftsmen, teachers, schoolchildren, children and their parents, for all ages and all skill levels.

What security measures need to be followed?

1. The first thing to remember when working with polymer clay is hygiene. Hands should be washed thoroughly after using polymer clay.

2. Children under eight years old are prohibited from working with polymer clay without parental supervision. This safety measure should not be used to protect the child from the use of such "dangerous material". Polymer clay is safe for humans. Its composition was brought to safety standards many years ago, and every year it is improving with the addition of natural ingredients. Here we are talking only about the safe use of polymer clay. Parents should not allow children to put clay fragments in their mouths, nose and other mucous membranes. Parents must observe safety precautions when firing clay. Don't let the kids do it on their own.
Also, do not allow children to gnaw or swallow ready-made (baked) polymer clay products. Do not use polymer clay to make kitchen utensils: plates, forks, and other items that come in contact with food. Polymer plastic can only be used to decorate items.

3. Firing of polymer clay must be carried out strictly at the temperature indicated on the packaging by the manufacturer. Remember that famous brands of polymer clay such as Sculpey and Fimo are baked at different temperatures - at 130 ° C, at 110 ° C. Always use to achieve the desired temperature.
It is also important to remember that the use of microwave ovens for firing is strictly prohibited, except for other polymer clays released directly for these purposes.
Be aware that microwaves do not create a temperature, they loosen the water molecule, which leads to heating of the product containing water. There is no water in baked polymer clay. Therefore, this will only lead to destruction of the structure of the plastic and / or possible damage to the microwave oven itself.
It is also important to observe the firing time. Usually, 30 minutes are allowed for complete baking of the product. For multiple firing (if you bake the parts separately), the initial baking time should be 10-15 minutes. The secondary is already calculated individually in order to total time baking was no more than 40 minutes. It is important to remember that the baking time also depends on the thickness of the product, the greater the thickness, the longer the baking time, but no more than 30-40 minutes.

If the temperature and time regime of firing is incorrect, the plastic itself may melt, which is characterized by a pungent odor. In this case, you need to immediately turn off the oven, open the window in the kitchen and only then open the oven door and immediately leave the kitchen until the room is completely ventilated.
If symptoms of poisoning appear: headache, dizziness, nausea, consult a doctor immediately.

Is polymer clay a hazardous toxic material?

Once again, I want to point out that polymer clay is completely safe when used correctly. As you already know, after baking, polymer clay turns into plastic. And plastic, in turn, tends to burn and emit combustion products hazardous to human health. What happens if you light a disposable plastic cup that is safe in everyday life (and if in your kitchen in the oven?)? The same thing happens when burning polymer clay.

Do I need to wash the oven after baking?

Yes, unfortunately, this is the only inconvenience when working with polymer clay. After firing, the plasticizer evaporated from the material is deposited on the walls of the oven. Therefore, if you are using the oven for cooking, it must be thoroughly washed with detergent beforehand.
Let me tell you one trick: some "lazy" craftsmen use the kitchen sleeve for baking. Polymer clay is baked in a sleeve, thereby preventing the plasticizer from settling on the walls of the oven. After such firing of polymer clay, it is enough to wipe the oven with a damp sponge. It's convenient and saves a lot of time.
You can also use a separate electric oven for polymer clay.

Does polymer clay need a work surface?

Since polymer clay is molded like plasticine, a work surface is a must. You can use any smooth surface: modeling board, ceramic tiles, glass, rug (which is specially designed for baking in the oven along with the product).
Do not use a table as a work surface. It can be damaged: scratched or covered with glue, varnish.
It is important to remember that if you are working with polymer clay, this work surface cannot be used for cooking. This also applies to tools such as (noodle cutter), etc.
Remember that particles of polymer clay can remain on any surface, even washed ones, and get into food.

Do I need special tools to work with polymer clay?

There are many different tools available. This is not to say that you need to purchase immediately. It all depends on what you are going to do or in what technique you will be working. So, first you need to decide on a creative direction: making jewelry, dolls, miniatures, etc.
Most of the craftsmen today are fond of jewelry. Therefore, in this article we will consider this direction.
What does a beginner need?
There are basic tools needed, such as a roller for rolling out plastic, a sculpting board (work surface),.
But again, it all depends on what you will do and in what technique. Usually, the tools are purchased by each craftsman individually. To get started, you can watch lessons on working with polymer clay and, based on a specific lesson, purchase the necessary tools.

How to work with polymer clay?

The first thing to do is to remove the packaging (cellophane) from the polymer clay bar. On each bar of polymer clay, the manufacturer makes grooves, there may be a different number of them depending on the brand and weight of the plastic. This is done for the convenience of work when calculating the amount of polymer clay for the details of the product. Most often, polymer clay is cut into equal parts along the grooves and, if necessary, each part is also cut into equal parts. It is so convenient to calculate how many equal pieces of polymer clay you need for a product. For example, you can adjust the size of the beads by adding or removing cut pieces of plastic.
Next, the polymer clay must be kneaded. Even the softest polymer clay needs to be kneaded. This is done in order to fully distribute the plasticizer and prepare the polymer clay for baking. Each part must be kneaded separately, it is better to start with a small piece (do not try to knead a whole bar of plastic in your palms at once, this is fraught with the appearance of corns and pain in the joints of the hands). After kneading the polymer clay in the palms, when it has already become soft and plastic (pliable), you can use special rolling tools: a roller or a pasta machine (noodle cutter).
It is important to remember that polymer clay is a very sticky material (dust and dirt particles remain on it) and is also easily soiled for hands, especially bright colors. Before and after working with each color of polymer clay, you should wipe your hands wet wipe.
It is also important to keep the polymer clay tools clean both before and after use. Remember that the pasta machine (noodle cutter) is not recommended to be washed with water (see. Maintenance do it yourself). It must be wiped with a damp cloth and dried. Pay particular attention to the use of an acrylic roller. After working with polymer clay, it must be thoroughly washed with warm soapy water, otherwise the roller may crack from interaction with the plasticizer contained in polymer clay.

How to get the perfect consistency (softness) of polymer clay?

Softness (ideal consistency) has no standards, it is selected individually for everyone.
In most cases, we knead the plastic so that it turns from hard to soft and pliable. But what if you find polymer clay too soft and uncomfortable to work with, especially when using various techniques?
In this case, you need to remove excess polymer (plasticizer):
Wrap the rolled polymer clay in parchment paper and press down with a load (book). Wait a few hours. Unfold the paper and remove the layer. You will see that there are oily stains on the paper - this is the excess plasticizer came out. Knead the plastic in your hands. If the polymer clay is still too soft for you, repeat the process.
Do not use newspaper or paper with a drawing, as the drawing may remain (transfer) on the plastic.
If the polymer clay remains too hard after kneading, you can use any plastic softener:,.

How to store it?

As we already know, baked polymer clay does not harden or air dry (there is no water in it). But at the same time, she is afraid of dust and dirt. Therefore, store polymer clay in plastic bag(in original packaging).
Many people think that plastic should be kept in the refrigerator. This is a misconception. Polymer clay is placed in the refrigerator to allow it to cool from the hands and take on a more solid form. But this is not necessary, polymer clay cools perfectly at room temperature.
Polymer clay is not afraid of cold. What about the heat?
Here comes the logic: since polymer clay hardens in the oven, then heat is contraindicated for it. Do not store polymer clay in the sun in summer. Some of the plasticizer can be burned off and become very hard.
So, to summarize: polymer clay should be stored in plastic wrap at room temperature.

What are the storage periods?

Polymer clay manufacturers indicate that baked polymer clay has no shelf life when stored properly. The only thing that can happen during long-term storage is the hardening of the plastic. That is why most of the well-known polymer clay manufacturers produce special softeners.
But on some packages of imported plastic, we often see a sticker with a Russian translation, where the expiration date is indicated. What does this mean?
This means that some suppliers of polymer clay to Russia are inattentive and indicate instead of the expiration date (and we remember that it is unlimited) the expiry date of the hygienic certificate for this product.
And why, then, is the expiration date also indicated on the domestic St. Petersburg plastic? The thing is that our manufacturer does not produce a softener, but using any imported softener for polymer clay, the shelf life for this plastic becomes irrelevant.

This article was written by Victoria Elsova and belongs to the site

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Polymer clay is "unfinished" plastic, namely unfinished polyvinyl chloride (PVC). Linoleum, plastic windows, electrical insulation, children's toys and many other useful things are also made from it. It is one of the most common plastics in the world.

PVC compositions used for various products also have a different composition. As a rule, they all contain PVC itself, a plasticizer (a substance that facilitates PVC melting), a filler, coloring pigments and various additives that facilitate production or give the finished products different beneficial features(light and heat resistance, frost resistance, etc.).

How is polymer clay different from ordinary plastic?

The factory makes a plastic toy from start to finish: they prepare the initial mass, give it the shape of a toy, and heat it to harden. And polymer clay is only mixed at the plant. And to sculpt from it, to bake it is a personal, creative business, and by no means a factory one. And when you sculpt and bake your masterpiece, you complete the process of making a PVC product, which we started at the Artefact plant.

Unlike the mass used in factories for the manufacture of toys, window frames and everything else, polymer clay should be easy to mold. It also needs to keep well, remaining suitable for sculpting for at least several years. The composition of polymer clay was selected by us so that during storage it does not harden, during molding it does not crumble or get dirty, and after baking it does not break.

An important difference is the non-toxicity of the components used in the composition of polymer clay. All the substances included in its composition are approved for use in children's products, and the polymer clay itself is regularly checked for compliance with the established hygiene requirements.

How to store polymer clay?

The main thing when storing polymer clay is to prevent it from heating. It is known from physics that thermodynamic processes continue at any temperature except absolute zero (0 ° C, or minus 273.15 ° C). The hardening of polymer clay is also a thermodynamic process, and it obeys a general law. This means that polymer clay hardens constantly, and the faster the higher the temperature.

If at 20 ° C it will take several years for it to turn into plastic, then already at 50 ° C 10 days will be enough, and at 120 ° C a few minutes are enough. Therefore, if you want to keep polymer clay longer, keep it in a cool place, away from the sun and heating appliances. You can even in the refrigerator if you really want to. Freezing does not harm polymer clay. Of course, before work, it must be kept at room temperature until it is returned to working condition.

The second rule is not to wrap polymer clay in paper or other absorbent substances. In this case, part of the plasticizer contained in the polymer clay will be absorbed into the packaging material, and the clay will lose its plasticity.

It is also undesirable to store polymer clay in an open package. Of course, plasticizers are not volatile, but they still evaporate. And it will be difficult to get rid of the settled dust.

It is best to leave it in its original packaging or wrap it in plastic wrap.

How to soften or harden polymer clay?

After reading how to store polymer clay, you have already understood that its gradual hardening is a natural and inevitable process, albeit a slow one. What if you need a softer material to complete the craft? Polymer clay can be softened by adding a special softener to it, and in its absence, any oil can be used (albeit with less success). Oils (vegetable and machine oils) dissolve in the plasticizer, which is part of the polymer clay, thereby, as it were, increasing the amount of the plasticizer. Don't get carried away! Remember that the original composition is balanced, and any additives (including a special softener) will significantly reduce the strength of polymer clay. There is also a side effect - clay with an excess of softeners will be more flexible after baking, and less durable with oils.

Now it is clear how you can make polymer clay harder? Correct - remove some of the plasticizer. It's quite simple - place the thinly rolled clay on clean, loose paper, and roll it up tight - like a carpet. After a while, the paper will be impregnated with the plasticizer, and the surface layers of the clay will become a little harder. Unroll the "carpet", remove the paper, stir the clay to make it homogeneous and, if necessary, repeat the procedure until the desired hardness is obtained.

The second way is to keep the material warm for some time, at 40 ... 50 ° C. In this case, the pieces of material should not be large, and the temperature should not be high, otherwise the outer part will harden too much, and the inner part will not have time to warm up.

And the third way is to intensively crush a piece of material. In this case, particles of polymer clay rub against each other, and this significantly accelerates the dissolution of PVC.

A tougher polymer clay is less plastic, it molds worse, but the craft keeps its shape better before baking. The harder polymer clay is also better for making small parts.

Why and how does it harden, and can it be softened again?

Contrary to popular belief, no chemical reactions during normal processing (as well as during production, by the way) polymer clay does not occur. Purely physical processes take place - dissolution, melting, solidification.

The fact is that before baking, polymer clay is a suspension of porous PVC grains (paste) partially dissolved in the plasticizer with the addition of an inert filler. Due to the absence of rigid bonds between the particles of the mass, it can be easily deformed (sculpted). When polymer clay is baked, high temperature PVC starts to melt. The presence of a plasticizer dramatically lowers the melting point of PVC grains. As a result, individual grains begin to fuse with each other already at 100 ° C, enveloping the filler particles, and forming a solid body, which is still fragile when hot, and even retains some flexibility.

When the product cools down after baking, the melted PVC hardens, just like melted glass hardens. PVC hardened under such conditions actually becomes the so-called solid solution of the polymer in the plasticizer. Due to the fact that previously solid particles passed into the solution, baked polymer clay is much harder than unbaked, and most importantly, there is no free plasticizer left in it, which previously served as a lubricant and facilitated modeling.

Most of the plasticizer that is part of the polymer clay is bound by polyvinyl chloride, but some of it evaporates, which is the reason for the appearance of a specific odor during baking.

Now, in order to return the polymer clay to its original state, it will be necessary to separate the plasticizer from the polymer, and even separate the grains that have fused together, return them to their original porous structure, and mix again with the plasticizer. You yourself understand that this is no easier to do than turning a well-done cutlet back into a piece of meat.

Why does the color change when baked?

The composition of polymer clay, as a rule, includes dyes - pigments or dyes. They are evenly distributed in the mass and paint it in the chosen color. But the color is determined not only by the pigment, it is also influenced by the structure of the material.

Remember, ice is transparent, and snow is quite the opposite, but both are just solid water. It's all about the structure - ice is most often homogeneous, and snow consists of snowflakes, each face of which reflects and refracts light in its own way.

Likewise, polymer clay, while not heated, consists of the smallest, light-scattering grains, which partially reflect the white light incident on them. After baking, the clay becomes solid, the light-reflecting edges disappear, and the incident light is reflected only by the pigment particles, and only rays of a certain color are reflected. That is why, when baked, the colors of polymer clay most often become darker, deeper, more saturated.

This is not at all a defect or a sign of poor material quality, as is sometimes thought. but the manifestation of the laws of light scattering and the mechanism of color perception of the human eye.

Of course, in violation temperature regime baking, the colors also change, and the polymer clay itself is irreversibly deteriorated, but this is a completely different story.

Why does polymer clay turn yellow when baked?

If polymer clay is baked at the recommended temperature (120 ... 130 ° C), it does not turn yellow and, moreover, does not turn black. If during baking polymer clay has acquired a yellowish or brownish tint, then you have significantly exceeded the permissible firing temperature.

Thanks to special additives, Artefact polymer clay can easily withstand temperatures of 135 ° C, and for a short time up to 140 ° C. However, we do not recommend that you abuse it. The fact is that, despite the absence of visible signs, when polyvinyl chloride is overheated, its decomposition begins with the release of hydrochloric acid (HCl) vapor. It is they who cause the yellowing of the material.

Further heating to a temperature of 150 ... 170 ° C will lead to the fact that the polyvinyl chloride will begin to decompose, and the products of its decomposition will burn. Like any combustion products, they will not add to your health.

Please, carefully monitor the observance of the temperature regime and ventilate the room!

What is the difference between transparent and classic colors?

Color change during baking is especially characteristic of translucent and transparent polymer clays. Unlike classic colors, transparent ones use a special filler, and air microbubbles that scatter light are removed. Therefore, when baked, such materials can change color in completely unexpected ways - for example, pale pink clay can turn into ruby, and pale green become dark emerald.

It should be noted that when working with transparent and translucent colors, in order to maintain transparency, it is recommended to avoid the formation of air bubbles when stirring and kneading the clay.

Classic colors, as a rule, have an opaque filler, or contain a significant amount of pigments. Therefore, despite the fusion of PVC particles, the transparency of the mass changes little in classic colors - the light continues to scatter almost in the same way as before baking, and the colors change to a much lesser extent.

Transparent and classic colors can be mixed, but this will saturate the material with light-scattering particles from the classic color, and transparency will be largely lost.

Why does polymer clay crack when baked and how to deal with it?

As a rule, all polymeric materials decrease in size during hardening - this is called shrinkage. It is caused, most often, by a change in the structure of the polymer material during melting and other processes. Shrinkage can be reduced by adding a filler to the material that does not change its structure during heat treatment. In this case, unfortunately, some parameters of the material may deteriorate. Shrinkage values ​​differ for polymer clays of different manufacturers and different collections of the same manufacturer.

Another reason for the appearance of cracks is the presence of inhomogeneities in the fired product - air bubbles, foreign inclusions (frame, additional dyes and fillers). Possible reasons- the use of materials from different collections and manufacturers in one craft, and internal boundaries section, for example when incomplete mixing of two pieces of material.

The third reason is uneven cooling. If you cool a massive craft immediately after baking, its outer layer hardens and shrinks, while the inner ones are still hot and take up a large volume. This is how an overripe watermelon breaks its rind.

The fourth reason is the laws of geometry. Even ideally homogeneous and uniformly heated material increases in volume in proportion to the third power (cube) of the radius, and along the surface - in proportion to the second (square). For this reason, sausages always burst along, and not across, during cooking. And in our case, when heated (especially fast!), A slightly caked and shrunken surface splits under the pressure of the inner heating layers. The second variant of the same trouble is that due to the fact that the volumetric shrinkage is greater than the surface shrinkage, multiple compressive stresses arise in the surface, generating microcracks, the so-called "scales".

All manufacturers are trying to reduce shrinkage, or somehow compensate for it, for example, by giving the material additional elasticity. However, it is helpful to follow some simple guidelines.

Do not heat or cool your products sharply, do it gradually, preferably in conjunction with the oven in which you bake them. Do not make massive, especially spherical products. If you need to blind, for example, a head, use as a base rolled from aluminum foil ball. Long and flat products are less prone to shrinkage cracking. When kneading and rolling plastic, try to avoid getting air between its layers.

More flexible types of polymer clays are less susceptible to cracking, and polymer clays containing a higher percentage of filler, such as the classic Artifact colors, shrink less than transparent and translucent ones containing a higher percentage of PVC.

How to bake properly?

The success of baking is largely determined by the quality of the oven used. Best results are obtained in a modern electric or gas oven with forced convection (built-in fan) with the grill turned off (or not). In such a furnace, due to the constant mixing of air, the temperature is the same throughout the entire volume, and there is no risk of burning one side and not baking the other. This is especially important for large items. All modern ovens automatically maintain the set temperature and are equipped with an electronic digital thermometer.

If you have to bake crafts in less perfect conditions, you must first make sure that the temperature is not exceeded. The easiest way to do this is to put a plate of white polymer clay in the cabinet for 20 ... 30 minutes. If, after removing it from the oven and cooling it down, it does not turn yellow and become strong at the same time, you can bake the crafts. Yellowing indicates a noticeable, up to 145 ... 150 ° C, temperature rise. And if the sample turns brown or even black, then the furnace is overheated to 160 ... 170 ° С. Reduce heat, cool oven, and retest. If the sample has not turned yellow, but has not gained strength either, then the oven is too cold.

It is risky to use small, inexpensive ovens - they often use open heating elements and primitive regulators that allow significant temperature fluctuations, especially during initial heating. Infrared (thermal) radiation of an open element is similar to the sun's rays - it strongly heats the side of the object facing it, but does not fall on the reverse side. As a result, one side of the craft will heat up much more than the other, and may simply burn out, while the shadow side will remain almost cold. This effect is especially strong on grills, never use the grill to bake polymer clay!

Polymer clay, like most non-metallic materials, does not conduct heat well. Therefore, baking a large product should be carried out with a gradual, slow increase in temperature so that the inner layers have time to warm up. Upon reaching the desired temperature, it is necessary to withstand the product the longer, the more massive it is, and then cool it down just as slowly, preferably together with the oven.

When determining the baking mode, one should proceed not from the mass of the craft, but from its maximum thickness - thin large products will warm up quickly, but spherical, even not too heavy, are more difficult to warm up.

The strength of baked polymer clay strongly depends on the baking temperature, gradually increasing to about 140 ° C. It must be remembered that there are no perfect ovens and thermometers, there are errors, and it is better not to heat up to the limit, you can accidentally exceed the temperature and ruin the craft. From a safety point of view, it is better to increase the baking time rather than the temperature to increase strength.

Do not use a microwave oven to bake polymer clay!

Why do thin plates bend and thick ones break?

This is explained by the fact that when we bend a solid plate, its upper layers tend to stretch, and the lower ones, on the contrary, contract.

In the body of the plate, especially near the upper and lower surfaces, forces arise that compress and stretch the material. The resistance of the material to these forces creates mechanical stresses. The material withstands these stresses up to a certain limit, and then begins to collapse - microcracks are formed. At this moment, a light line appears on the polymer clay plate - we see light scattered and reflected by the walls of the cracks. Further mockery of the material will lead to an increase in the size and number of cracks, and then to its destruction - the plate will break.

The thinner the plate, the less mechanical stress, it bends more easily, it can be bent to a greater angle without breaking, and it can withstand more bends. Therefore, it is better to make the petals and leaves of flowers made of polymer clay thinner, they will break less. Thick plates are much more difficult to bend, but when bent, they will break earlier, since mechanical stresses in them grow faster.

And mechanical stresses depend on the properties of the material - elastic (like rubber) materials do not break at all when bent, since they are easily compressed and stretched. From this point of view, the Chiffon collection is better suited for petals and other delicate elements. A thin leaf from "Chiffon" can be twisted into a tube with impunity, and a thin sausage in general can be tied in a knot.

What and how much can you add to polymer clay?

A variety of liquid and solid substances can be added to polymer clay, but this is almost always accompanied by a deterioration in its properties. However, a competent and creative introduction to the composition of additional, including completely alien components in reasonable quantities, sometimes allows you to achieve impressive effects.

Slight additions of water or alcohol-based contrast inks allow you to get an imitation of veins in the stone. The addition of shredded foil creates a play of light similar to some rocks.

The addition of a special softener or oil makes the polymer clay softer and increases the elasticity of the baked clay, and the addition of dry filler (talc, kaolin, tooth powder) makes it harder (and also reduces the strength of the baked one).

Additives of colored powder fillers are colored in the appropriate color. Surface rubbing of aluminum, copper, bronze and graphite powders allows you to simulate almost any metal and alloy.

But an attempt to turn a classic polymer clay into "metallic" by adding metallic pigments (powders) to the mass is futile. Metallics require a transparent base, while classic colors have too much opaque filler and pigments.

Methods and artistic techniques of use various additives very well designed by polymer clay craftsmen.

Plastic, also known as polymer clay, is an excellent material for the creativity of adults and children. The material is affordable and opens up a truly unlimited scope for self-expression. Novice craftsmen quickly face the problem of winding the mass and losing its original properties. You can avoid this, but you will need to follow certain rules for storing plastic. Since baked and self-hardening materials differ in composition and characteristics, they should be stored in different ways.

Temperature regime

Create some special conditions no need, any type of polymer clay can be kept at room temperature. The baked mass can be stored in the refrigerator or frozen - sometimes it is even recommended for storing finished products before heat treatment. But self-solidifying plastic contains water, which crystallizes in the cold, so storage in a refrigerator or freezer can greatly affect its characteristics.

Storage

Proposed at the link http://www.tairtd.ru/shop/polimerna-glina-i-massy-dlya-lepki/ polymer clay High Quality can resist negative influences for a long time environment, but it's better to transfer the whole experiment to the area of ​​creativity. Keep the material away from straight lines. sun rays, heaters and other hot items. Otherwise, the mass may fade, become brittle or even completely harden.

Storage container

Unopened packages can be left as they are for quite a long time - this will not harm the material. But after opening the pack, it is important to comply with several conditions. The baked clay does not set in the air, but this does not mean that it should be left like this: the adhesion of villi, dust, fine debris can ruin the appearance of the products, as well as worsen the adhesion of parts to each other. In addition, the synthetic plasticizer will gradually evaporate. It is advisable to wrap the raw material in wax paper, plastic wrap or cling foil. Do not allow the unbaked mass to come into contact with other polymers, finished products, foam, polyethylene. Do not wrap plastic in plain paper.

Self-hardening masses should be protected from contact with air by tightly wrapping with foil or placing in a sealed bag with a fastener. You can also use a plastic container with a damp cloth inside to help create a favorable climate for the leftover material.