The flower raft is a multi-stemmed vase that provides an opportunity for complex and exuberant flower arrangements. Dutch tulipieres and Chinese multi-stemmed vases from the Song dynasty have been important historical references. However, the flower raft
is a synthesis of other influences: the chimneys of grand English manors, the hull of the ironclad Monitor from the civil war, factory smoke stacks, and blast furnaces remembered from my childhood near Cleveland, Ohio. There is both challenge and
playfulness in creating these hybrid forms.
Throwing Segments
The flower rafts are created from several wheel-thrown and altered parts, and I also use handbuilding techniques to alter and assemble the parts in new ways. Using this process of building has added variety to the forms that I make. Improvisation and
invention allow new forms to evolve.
Begin by throwing the main body form of the flower raft on a plastic throwing bat with 3 pounds of clay. Throw the main body into a tapered cylinder that is widest at the bottom (figure 1). It’s important to throw this form without a bottom so that
it can be easily altered later. Next, shape the form with ribs and a sponge until it has two tapered segments. Finally, the top of the form is collared inward until it’s enclosed and sealed (figure 2).
Next, roll out a slab from 3½ pounds of clay that has the same thickness as the main body. This slab will form the base of the flower raft. The width of the slab should be at least as wide as the diameter of the bottom of the main body, and the
length of the slab should be at least twice the height of the main body. Let the thrown form and slab dry until they’re both soft leather hard—pliable, but firm enough to handle without distortion.
At this point, you can throw a number of bottomless stem shapes off a large hump of clay (figure 3). This method provides a quick way to throw many small forms. Throw more stems than you think you’ll need. Vary the size, shape, and texture of each
stem so you have a lot of options to choose from during the assembly process (figures 4 and 5). Dry these stems to a soft leather-hard state to match the dryness of the previously made pieces.
Altering the Form and Assembly
Now, you can begin to alter and assemble each form. First, use a sharp knife to split the main body form from top to bottom into two equal halves (figure 6). Rearrange the two halves so that the cut sides become the bottom and the original bottom edges
are joined together to create a new arch-like form that’s long and low. It’s important to secure this seam together on both the inside and outside to prevent cracking (figure 7). Place this new form on the clay slab and trace its outline.
Then pick up the form, score and apply slurry to its bottom edge, and to its outline on the slab. Place the form back on the slab and join all the seams together carefully. Trim the excess slab away, leaving about a ¼-inch foot projecting around
the whole form (figure 8). Use an altered rib as a template to create a consistent, rounded profile to the foot. My altered rib was made from an old plastic gift card with a ¼-inch, curved notch cut out of one corner (figures 9 and 10).
Next, add the stem parts on top of the newly constructed base form. Since the base has an arch-like form, it’s strong and can easily support multiple stems. Attach the stems with a method similar to adding a spout on a teapot. Carefully cut and
shape the bottom edge of each stem so it joins flush against the base form. Before joining the stem, trace the stem position, cut a hole into the main base form that is slightly smaller than the stem so that the stem has a ledge to stand on (figure
11). I generally put the main stem in the center position. This tall stem is made from two stacked parts (figure 12). Smaller, narrower stems are added on either side and lately, I’ve been using contrasting stems to break up the symmetry of
the form and create variation and interest (figure 13). Lastly, clean up the attachment joints with either a moist sponge or soft brush.
Dry the assembled forms very slowly to prevent the seams from cracking.
Glazing
In a soda kiln, pottery forms become individualized as the soda atmosphere changes the color and texture of the clay and glazes in subtle and unique ways. I select glazes that are responsive to the turbulent atmosphere of the soda kiln.
Recently I have been spraying glaze onto the exteriors of the flower rafts after pouring a liner glaze inside. Pour VC Amber Celadon glaze into the pot and tilt it back and forth to coat the interior evenly. Tip the form over to drain the glaze out through
all of the stems so they too are fully coated with glaze. VC Amber Celadon is fluid, glossy, and seals the form making it water tight. Next, spray the outside of the pot with a series of glazes applied in thin layers. First, spray Woo Yellow glaze
evenly over the entire form and allow it to dry. Next, spray Oribe glaze with a greater thickness toward the top of the form (figure 14). Lastly, spray Cobalt Blue glaze thinly on the tops of the stems.
Soda Firing
The kiln I use has about 35 cubic feet of stacking space. During the firing, I use a moderate body reduction at cone 08 for ½ hour then fire in very light reduction until cone 8 is soft. At this point I mix the soda solution. (A solution of two
pounds of soda ash dissolved in one gallon of warm water provides a good ratio. I use a simple pump garden sprayer with an all-metal wand to spray the soda into the kiln.) I clean up the flame in the kiln to create an oxidation atmosphere before spraying
the soda. This helps prevent excessive gray carbon trapping in the glaze. I start to spray soda when cone 8 is down and spray into four soda ports—two ports in the front of the kiln and two in back of the kiln. The spray enters over the hottest
parts of the kiln; the burner troughs and bag wall areas. I don’t spray directly onto the pottery. I make several slow circuits around the kiln spraying into the soda ports. It takes about 15–20 minutes to spray all of the soda solution.
When the soda spraying is complete, cone 9 is usually bending. Then I return to fire in a very light reduction atmosphere until cone 10 is halfway down in all locations. Ideally, this part of the firing continues for about 45 minutes to an hour. This
extra firing time allows the soda to melt thoroughly on the surface of the pots.
Mark Johnson lives and has his studio in South Portland, Maine. He teaches at Maine College of Art. See more of his work at www.markjohnsonceramics.com.
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The flower raft is a multi-stemmed vase that provides an opportunity for complex and exuberant flower arrangements. Dutch tulipieres and Chinese multi-stemmed vases from the Song dynasty have been important historical references. However, the flower raft is a synthesis of other influences: the chimneys of grand English manors, the hull of the ironclad Monitor from the civil war, factory smoke stacks, and blast furnaces remembered from my childhood near Cleveland, Ohio. There is both challenge and playfulness in creating these hybrid forms.
Throwing Segments
The flower rafts are created from several wheel-thrown and altered parts, and I also use handbuilding techniques to alter and assemble the parts in new ways. Using this process of building has added variety to the forms that I make. Improvisation and invention allow new forms to evolve.
Begin by throwing the main body form of the flower raft on a plastic throwing bat with 3 pounds of clay. Throw the main body into a tapered cylinder that is widest at the bottom (figure 1). It’s important to throw this form without a bottom so that it can be easily altered later. Next, shape the form with ribs and a sponge until it has two tapered segments. Finally, the top of the form is collared inward until it’s enclosed and sealed (figure 2).
Next, roll out a slab from 3½ pounds of clay that has the same thickness as the main body. This slab will form the base of the flower raft. The width of the slab should be at least as wide as the diameter of the bottom of the main body, and the length of the slab should be at least twice the height of the main body. Let the thrown form and slab dry until they’re both soft leather hard—pliable, but firm enough to handle without distortion.
At this point, you can throw a number of bottomless stem shapes off a large hump of clay (figure 3). This method provides a quick way to throw many small forms. Throw more stems than you think you’ll need. Vary the size, shape, and texture of each stem so you have a lot of options to choose from during the assembly process (figures 4 and 5). Dry these stems to a soft leather-hard state to match the dryness of the previously made pieces.
Altering the Form and Assembly
Now, you can begin to alter and assemble each form. First, use a sharp knife to split the main body form from top to bottom into two equal halves (figure 6). Rearrange the two halves so that the cut sides become the bottom and the original bottom edges are joined together to create a new arch-like form that’s long and low. It’s important to secure this seam together on both the inside and outside to prevent cracking (figure 7). Place this new form on the clay slab and trace its outline. Then pick up the form, score and apply slurry to its bottom edge, and to its outline on the slab. Place the form back on the slab and join all the seams together carefully. Trim the excess slab away, leaving about a ¼-inch foot projecting around the whole form (figure 8). Use an altered rib as a template to create a consistent, rounded profile to the foot. My altered rib was made from an old plastic gift card with a ¼-inch, curved notch cut out of one corner (figures 9 and 10).
Next, add the stem parts on top of the newly constructed base form. Since the base has an arch-like form, it’s strong and can easily support multiple stems. Attach the stems with a method similar to adding a spout on a teapot. Carefully cut and shape the bottom edge of each stem so it joins flush against the base form. Before joining the stem, trace the stem position, cut a hole into the main base form that is slightly smaller than the stem so that the stem has a ledge to stand on (figure 11). I generally put the main stem in the center position. This tall stem is made from two stacked parts (figure 12). Smaller, narrower stems are added on either side and lately, I’ve been using contrasting stems to break up the symmetry of the form and create variation and interest (figure 13). Lastly, clean up the attachment joints with either a moist sponge or soft brush.
Dry the assembled forms very slowly to prevent the seams from cracking.
Glazing
In a soda kiln, pottery forms become individualized as the soda atmosphere changes the color and texture of the clay and glazes in subtle and unique ways. I select glazes that are responsive to the turbulent atmosphere of the soda kiln.
Recently I have been spraying glaze onto the exteriors of the flower rafts after pouring a liner glaze inside. Pour VC Amber Celadon glaze into the pot and tilt it back and forth to coat the interior evenly. Tip the form over to drain the glaze out through all of the stems so they too are fully coated with glaze. VC Amber Celadon is fluid, glossy, and seals the form making it water tight. Next, spray the outside of the pot with a series of glazes applied in thin layers. First, spray Woo Yellow glaze evenly over the entire form and allow it to dry. Next, spray Oribe glaze with a greater thickness toward the top of the form (figure 14). Lastly, spray Cobalt Blue glaze thinly on the tops of the stems.
Soda Firing
The kiln I use has about 35 cubic feet of stacking space. During the firing, I use a moderate body reduction at cone 08 for ½ hour then fire in very light reduction until cone 8 is soft. At this point I mix the soda solution. (A solution of two pounds of soda ash dissolved in one gallon of warm water provides a good ratio. I use a simple pump garden sprayer with an all-metal wand to spray the soda into the kiln.) I clean up the flame in the kiln to create an oxidation atmosphere before spraying the soda. This helps prevent excessive gray carbon trapping in the glaze. I start to spray soda when cone 8 is down and spray into four soda ports—two ports in the front of the kiln and two in back of the kiln. The spray enters over the hottest parts of the kiln; the burner troughs and bag wall areas. I don’t spray directly onto the pottery. I make several slow circuits around the kiln spraying into the soda ports. It takes about 15–20 minutes to spray all of the soda solution.
When the soda spraying is complete, cone 9 is usually bending. Then I return to fire in a very light reduction atmosphere until cone 10 is halfway down in all locations. Ideally, this part of the firing continues for about 45 minutes to an hour. This extra firing time allows the soda to melt thoroughly on the surface of the pots.
Mark Johnson lives and has his studio in South Portland, Maine. He teaches at Maine College of Art. See more of his work at www.markjohnsonceramics.com.
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