How Porcelain is Created

What does a porcelain cup start with? A crazy idea and thorough calculations. Porcelain is not a plastic material; it's incredibly difficult to mold. For sculptural molding, there are only two types of porcelain: Audry Blackman and paper porcelain. For everything else, there's slip-that is, liquid porcelain mass. That's what I use to cast my cups.

The first step is creating a clay model. I calculate the model's size so that after firing, the cup turns out to the desired volume. For this, the initial form must be 12-15% larger. The model also needs to be created taking into account that the porcelain item won't break when removed from the mold. So, I carefully calculate all the turns, angles, and plan in advance where the facets of the plaster mold will be located.

Once the clay model is complete, we move on to creating the plaster "permanent" model. For this, we cover our clay figurine with a special oil-soap composition, build a fairly sturdy structure from plexiglass, hot glue, and plasticine, and pour plaster into it. I do this in two or three iterations because my models are quite complex, so it's better to make the mold for the future plaster casting little by little. Once the plaster has set, I remove the clay model, cover the mold with the oil-soap composition, securely fix all the joints, and pour plaster inside. For the plaster model, the plaster needs to be of the hardest varieties, poorly absorbing water, so that the model doesn't break or come into contact with the plaster mold. After setting, the model is carefully sanded, adjusted, and coated with shellac.

Hooray, we can move on to the third step! Creating the plaster mold. The most responsible stage. So, very attentively and thoughtfully, we mark the plaster model, drawing the locations of the facets of the plaster mold. A half-millimeter error will cost the integrity of the item. So, we can't make a mistake. Along this marking, we'll build the facet part of the mold from special plasticine. It should easily come off the item but hold well when assembled. So, we check all the angles 10 times and only then build the formwork into which we'll pour the plaster. The plaster for the mold needs to be of a different grade. Softer, well-absorbing water. Working with such plaster is more difficult because it sets very quickly. So, after everything is again coated with the oil-soap solution, we quickly and precisely prepare the plaster. It needs to be mixed carefully, fast enough, without letting air in. And as soon as it thickens, pour it carefully into the formwork, checking for air bubbles or lumps. Once the plaster has set enough and become cold, we disassemble the formwork and carefully separate the facet of our future mold. It needs to be processed, removing sharp edges and making locks for connection with the next parts. Then, the other parts of the mold are created the same way. For my simplest works, I make molds from three parts, but most often from four or more. This first mold must be perfect! Because based on it, you can make subsequent ones and even restore the plaster model if something happens to it.

The finished molds are washed and sent to dry. For porcelain, they must be completely clean and dry. And we move on to the fourth step-preparing the porcelain slip.

In principle, you can buy ready-made slip. But some porcelains I need are sold only in block form. So, we take demineralized water, deflocculants (there are many different ones, but I prefer derivatives of carbonic acid), a block of porcelain, and a very clean bucket. We need to make the porcelain liquid while keeping the moisture level around 27-30%, so we calculate the amount of water relative to the humidity of our block. The porcelain is broken into small pieces and submerged in water for a day. Once it's sufficiently soaked, it needs to be stirred with a whisk, add the deflocculant, stir again to a homogeneous mass, filter through a fine sieve, and let it settle for another day. There should be no bubbles in the porcelain slip! So, all actions with it must be done carefully and slowly, with constant settling and tapping.

All preparations are complete; we can cast the cup. So, step number five! We assemble the plaster mold, securely fixing it, for example, with very tight rubber rings. We stir the porcelain, pour a small amount while straining it through a sieve, removing air bubbles. Now, carefully but quickly enough, pour the porcelain into the mold through the sieve. Remove the air bubbles that have again entered the porcelain. Wait a few minutes, carefully monitoring the thickness of the wall that will form at the edge of the plaster. Once the desired thickness is achieved, drain the porcelain slip and leave the mold in an inverted position so that the remaining porcelain doesn't accumulate at the bottom. When our item loses its wet shine, the mold can be turned to the normal position and the set porcelain mass trimmed along the shape of the upper edge. We need to wait until the plaster has absorbed enough water so that our item easily comes off its walls. Now, disassemble the mold, remove the cup, remove the seams that inevitably form at the mold joints, even it out, and set it to dry. For complete drying, the item needs about 24 hours at +22 degrees and about 60% humidity.

Step six. The dried item needs to be smoothed with water and a sponge without over-wetting it. Then, carefully polish it with fine sandpaper. Done!

Step seven-send the cup to firing at 1050 degrees. In about 32 hours, it will be ready.

The kiln has cooled; the item can be removed. We move on to the eighth step. First, the cup must be washed from dust and polished with sandpaper, then washed again. Then, cover with underglaze paints (if you want to add color) and glaze. I do this with a brush because I cover the item partially. This takes more time than the dipping method, but it allows preserving the texture of the porcelain. Remove bubbles and unevenness on the glaze surface and put it in the kiln for firing at 1220-1280 degrees. Before using the glaze, I ALWAYS conduct tests. Otherwise, we'll learn that the manufacturer slightly changed the formula from the shards... At this stage, there's often a lot of waste because porcelain is a fairly capricious material. But I'll tell you more about that in the article on firing.

After 36 hours, you can remove the item and move on to applying luster varnishes and noble metal preparations. Step nine. Wash the item again from combustion byproducts. Even if they're not visible, they're still there! Dry the item and apply gold, platinum, or luster. This needs to be done in a very well-ventilated room because they have a sharp, unpleasant smell. For a "marble" effect, I pre-cover the items with converters, then apply the varnishes. The dried items can be put back in the kiln at 800-820 degrees. This is the fastest firing; after 17-20 hours, you can open the kiln.

And the final, tenth step: thoroughly wash the items from luster dust. I do this in the dishwasher at the highest temperature.

All done-the cup is ready! Now you can brew coffee 🙂

From the moment of the idea to creating the finished product, it takes from two to four weeks. But it's worth it!