Refer From: How we made a ceramic and porcelain product?
- Step 1. The raw material selection
- Step 2. Keading mud
- Step 3. Shape the porcelain
- Step 4. Dry in the shade
- Step 5. Trim the porcelain
- Step 6. Biscuiting
- Step 7. Hand painting under the glaze
- Step 8. Glazing
- Step 9. Loading the kiln
- Step 10. Glazed firing
- Step 11. Out of the kiln
- Step 12. Painting on the glaze
- Step 13. Decoration firing
- Step 14. Finished work
Step 1. The raw material selection
The raw materials for firing porcelain are mixed by china clay and regular clay. Over one thousand years ago, handicraft men traveled thousands of miles to look for the right material for firing porcelains. After countless failures to find the right portion of china clay and regular clay for perfect porcelain firing, eventually the final portion was able to go through high temperature firing over 1200-1380C (2190-2520F). The skill of high fire porcelain has been practiced carefully up to now.
Step 2. Keading mud
Knead mud to keep the water well proportioned in order to keep each part not too soft and not too hard. Push the air out of the clay to prevent from crack during the firing.
Step 3. Shape the porcelain
Put the mud on the special wheel and use the centrifugal force generated by the wheel to shape the porcelain body.
Step 4. Dry in the shade
Dry the porcelain in the shade to squeeze out the water inside before entering the kiln.
Step 5. Trim the porcelain
Trim the porcelain after drying in the shade. There might be marks left on the porcelain after drying process. Trimming the surface of the porcelain to make sure it's smooth and clean and ready for glazing and firing in kiln.
Step 6. Biscuiting
Biscuiting refers to any pottery that has been fired in a kiln without a ceramic glaze. This can be a final product such as biscuit porcelain or unglazed earthware.
Step 7. Hand painting under the glaze
Paint the patterns on the porcelain after biscuiting. Use transparent glaze to cover the hand painting. Fire the porcelain under high temperature between 1200-1400C(around 2000F)The finished porcelain present with beautiful patterns under the shiny glaze. The glaze is good to reserve the painting for a long time.
Step 8. Glazing
Brush glazing: it's a method fit for small area of glazing. The effect is better with using traditional sheep hair calligraphy brush.
Step 9. Loading the kiln
Carefully control the distance between each porcelain to prevent from sticking to each other. Those irregular shaped porcelains need extra attention especially. Each piece of finely handmade work needs to stay 2mm from the others.
Step 10. Glazed firing
Glazed firing is a process after biscuiting. High temperature is set at 1200-1380C (2190-2520F). During the process, handicraftman needs to constantly check with the fire to make sure the effect. It largely depend on the experience of the specific person.
Step 11. Out of the kiln
After the high temperature firing, the kiln starts to cool down. We can take the plug off from the kiln to accelerate the temperature falling. Once the temperature hit blow 100C(...F) , we can open the door of the kiln to take out the porcelains.
Step 12. Painting on the glaze
It's one of the important skills for making porcelains. The skill first started in Song Dynasty and matured in Ming Dynasty. Paint beautiful patterns on the clean and glazed white porcelains.
Step 13. Decoration firing
Porcelains with decoration firing need to be send back to kiln for a second time. Using low temperature firing between 600-900C (1110-1650F) to solidify the patterns on the appearance. Due to different color requires different temperature, multiple firing process is necessary.
Step 14. Finished work
After careful check from the experience handicraftmen, the quality must satisfy the certain standard to present.