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Perception was a wall piece. 28″ by 12″
I made the design in paper. I numbered each section and I transferred to a thick plastic to put on the clay. After I used the slab roller to make the tile. For this project I used a thick surface, laminate plywood 1.5 “, covered in plastic. When I put the clay on top I covered the borders too.
I tried to keep the borders in place using foam tape and plastic strips around the piece. I think next time I would like to use a ratchet tie down.
I fired cone 04
I glazed and fired cone 04
I used a little brown grout in the frame.
I tried to use different surfaces to make tiles flat. I tried wood, plywood and drywall covered with canvas. In the past when I was working with very thin wood surfaces I had problems with warping corners or deformed pieces. The wood surface absorbs humidity from the clay and starts warping, therefore the piece warps too. A rigid surface is the best choice. I had better results with 1″ Plywood or drywall.
I think everything depends on the scale of the piece that you are doing. Small pieces can be very flat and dry evenly when you place the piece on rigid metal store rack surface. Laura Reuter wrote a great article about it.
The pieces below were made using four different clay bodies including porcelain. I used a drywall surface but I set an other drywall board on top to apply weight.
1. Rigid surface. Plywood 1″ thick or drywall.
2. Score in the back.
3. Always put plastic on top and bottom.
4. Large scale pieces are better to make on a big table, and if possible only move it to put in the kiln.
5. For making a relieve piece, put little weights on the corners to prevent warping.
I collected all my panoramic pictures from the city of Saint Petersburg for a couple years. I love the architectural landscape, especially the view from the pier.
I made my own sketch of the city.
I divided the sketch of the city into four sections. With the slab roller I created the tiles. I left it to dry for a day. I put a board on top of each. I transferred the design to the tiles. I found the best stage to carve porcelain is leather hard. You have to work very fast to avoid cracks. I keep the four tiles together when I carve the city, continuing the buildings over the borders. Using the same surface thickness boards helps. Remember to cover the parts that you don’t work on with plastic.
“How wonderful it is that nobody need wait a single moment before starting to improve the world.”
“For the dead and the living we must bear wittiness.”
Everything is about respect, through art people can heal themselves and transmit powerful feelings. I sketched these pieces because they had a big impact on me.
I would highlight in particular the artist Alfred Tibor
I saw a beautiful exhibition in glass last Friday, Boyd Sugiki
and Lisa Zerkowitz’s at the Chihuly Collection Museum Saint Petersburg.
I love sculpture and Architecture. I’m very interested now in learning the simplification of forms. I was amazed at the sculptural designs, it is very important to understand the negative and positive space. The work of these two great artists Boyd Sugiki and Carlo Scarpa are perfect to understand.
I believe that most of the time when we don’t have a good result, it is not because we didn’t use the right product or formula it is because the piece was in a different stage of dryness. Below are some simple ways to understand the stage of the clay when you make a piece.
|Characteristic||Stage of the clay|
|wet, but not sticky||Leather Hard Soft|
|feels cool and stiff||Leather Hard Stiff|
|room temperature ready to fire||Bone Dry/Green ware|
The perfect stage of clay to fix a crack or join together is leather hard soft. To return from leather hard stiff to leather hard soft you have to cover the piece with a wet paper towel then cover with plastic , then wait a least 1 day.
But you have to remember if your piece is bone dry/greenware it is not easy, it will be require a lot of patience to return your piece to earlier stages. Sometimes when I try to wet the piece and cover it with wet paper and plastic for one day it is not enough, I have noticed the surface is wet but not the internal part, especially if it is thick. You have to repeat the process again until the piece is leather hard soft.
I tried many different recipes and products to join and repair pieces. My goal was to find what works for each stage. I struggled with commercial products. Most of my pieces are complex in structure and thickness I believe the products work, the pieces were attached, but I have problems later.
Stop the crack before you fix it
Something that I tried is to make perpendicular lines at the ends of the crack before I fix it. If you don’t do it the fissure tends to keeps going creating very thin hairlines at the ends. I saw that in porcelain because it is more unforgiving.
I tried slip, Paper clay, Bone dry clay with vinegar, Miracle water, Sodium Silicate, Commercial products. Below are the best results in each stage of the clay.
|Plastic (Stage of the clay)|
In the plastic stage it is easy to join. The same clay with out water can work too.
|Leather hard Soft (Stage of the clay)|
√ Paper clay
√ Bone dry clay with vinegar
√ Miracle water or mender
√ Miracle water Sodium Silicate
√ Commercial products
Leather hard Soft is perfect to repair and join, This is the process to attach two parts: 1. score both parts. 2. use your mender on both parts. 3. Put a coil of soft clay between both parts.
|Leather hard Stiff (Stage of the clay)|
|√ Paper clay
√ Bone dray clay with vinegar
√ Miracle water
√ Commercial Products
To repair and join at Leather hard Stiff , I wet the two pieces and cover with wet paper and plastic. Then wait until the two parts are in leather hard soft.
|Bone dry/ Green ware (Stage of the clay)|
|√ Miracle water
√ Miracle water Sodium Silicate
√ Commercial products
When I join and repair in Bone dry stage, I have to fix it more than once. In porcelain pieces sometimes repairing takes more than 4 times, it is time consuming. Apparently good results in the bisque fire, the pieces are attached and cracks are fixed, but in the second fire you see the glaze shivering, the glaze peels off showing the crack.
|After Bisque cone 04 (Stage of the clay)|
|√ Paper clay
√ Miracle water
√ Commercial Products
Most off my pieces that I fix after bisque and re-fire to cone 04 with or without candling the piece, the clear glaze on top starts shivering too.
Using only Sodium Silicate leaves orange color and you can still see the fissure.
I know I’m learning, this is not about restoring, my emphasis is about finding the way the save pieces that are difficult to make again. Using the right mender in the best time. Nevertheless I find the best of all for me was paper clay in leather hard soft stage. Less ingredients in your mender is better, there are less chances of altering the process of fire and glazing.
I tried to improve the results of my slips, using bone dry clay hammered into small pieces and less water. Blend in electric blender, wait one day.
Very good article about deflocculation slip
Magic Water Recipe
1 gallon water
3 table spoons of liquid sodium silicate
1 1/2 teaspoons of soda ash
Lana Wilson recipe
Good article about Paper clay
How to prevent cracks
Planning: Porcelain dries faster than other materials than I have used before like raku or phoenix and if you go thinner you need to be even more careful. I agree that you have to play with the material to know its proprieties first then you have to realize that everything is possible if you make a plan. Sometimes we concentrate on what we want to do, but we don’t have a plan on how we can do it. Is the piece going to involve carving? Does the piece need structure? What support material do you have to make, if the structure that you are going to use is like foam, does it let the clay dry is at the same time?
Work surface: If you choose drywall to use for your work surface, remember to put duct tape on all borders. The drywall has plaster inside like you see below in the picture , if these particles mix with the clay, they can be the cause of a blow up.
I made this frame for a mirror using porcelain a couple of years ago, it was my first piece using P10. In my head I had a vision of my piece, but I didn’t plan so well how I was going to make it.
Because I had the studio far away I had to transport the piece. I used a thick piece of wood for a work surface and I used a thick black plastic, in the center I used cardboard to cover the space for the mirror. I learned that using wood without plastic is not good because the wood absorbs humidity from the clay. Thick plastic is no good either because it doesn’t dry at the same rate as the top, the clay is much better to dry at the same rate; top and bottom to prevent cracking. Delicate pieces are much better to make on top of the kiln shell, that way you don’t have to lift it.
Time: I found out it is very import to estimate the time it takes you to make the piece not only because you would like to track the time also to choose the type of plastic to cover the piece.
I carved all the corner figures without covering the frame with plastic. All the borders started to crack and warp. I solved this by covering with wet paper towel for one day.
I found out if I don’t have too much time in the same week to work on the piece you can cover it with wet paper towels, (the best is Scott 55 , you can find it at Home Depot) then you can use plastic Press’n Seal from the kitchen, because it is sticky so you can seal all the corners.
Using the right tool:When you use the slab roller: be careful with all borders, all the cracks will try to continue, pressing all borders helps. To prevent bubbles you can use the pinch tool to open any bump.
Knives: Remember, a line made with the knife in porcelain will try to continue creating a crack. Rounding all the angles helps, you can use a wet makeup sponge rubbing very gently or use a very thin brush. Turning the knife before crossing the intersection of two lines helps to prevent cracks, the same movement that you use to turn the pencil when sketching or drawing.
Sharp tools: It is very efficient when your tools are sharp especially if you like to carve. Unfortunately you can leave a mark that creates cracks when you use a dull tool.
There are a lot of reasons why a piece cracks, I think I have experienced every single situation. Some cracks can be prevented before you make a piece, other are invisible in the bisque fire but can be visible after the second fire or can be visible months after you fire because the fit of the glaze.