Frosted Vessels by Robert Chamberlin, finished vessel

In college, I connected cake decorating techniques, something my mom did for extra money, with ceramic materials. I have been pushing what is possible with piping techniques and thick, frosting-like slip for the last 13 years while making artwork about desire, wealth, and power. After much experimentation, the recipe and method I have developed create a slip that is thick and able to hold fine details when piped. 

Supplies 

  • 100 pounds of cone-6 Frost porcelain 
  • Two five-gallon buckets 
  • Water 
  • Drill with a cement mixing attachment 

Creating the Slip 

Begin by breaking up 50 pounds of fresh-out-of-the-bag porcelain (or whatever clay body you use) into a bucket (1). I aim for pea- to grape-sized pieces. Pour water into the bucket so that it just barely covers your clay pieces (2). I underfill and shake the bucket until all the clay is underwater (3). After letting your clay and water sit for at least 24 hours, drain off as much excess water as possible. Using a strainer or getting help from a friend to hold back the clay can be very helpful. Mix the remaining slaked clay with a drill and cement mixer attachment (4). 

1 Pinch fresh clay into small gobs to make slaking and mixing easier. 2 Add water until it barely covers the clay. Use as little water as possible.

3 Shake the bucket until all the clay is underwater and let it sit for 24 hours. 4 Drain off the water on top, then blend with a drill with a mixer attachment.

Separate this slip mixture into two 5-gallon buckets and repeat the process with 25–35 pounds of additional clay using the slip you just mixed to cover your new clay pieces. Let sit for at least 24 hours before mixing. This usually achieves a thick frosting consistency, but if your ideal viscosity hasn’t been achieved, add more clay, let it sit, and mix again until the desired thickness has been achieved. I look for stiff peaks as a cue that I have the correct texture. This can be adapted to any quantity, just remember that if you want a thick slip, using as little water and draining as much water as possible is crucial. 

To add color, I measure a small amount (less than 1 cup) of slip, add Mason stain, and mix until fully incorporated. Sometimes a very small amount of water is helpful to get it fully mixed. Then, I add the colored slip back into the rest and mix until combined. This method of mixing allows for better color distribution throughout the slip. 

Printing with Lace 

I paint with lace by using it like a silkscreen or stencil. I find that cheap machine-made lace works best. Fine handmade lace has never worked well for this process, from my experience, because it is too thick and absorbs too much slip (it is excellent for pressing into a slab, though). For this technique, I use a thinner slip than I do for the piping process. To make this thinner slip, I add water to my piping slip until it’s around the texture of screen-printing ink or sour cream—barely solid. 

5 Using synthetic lace as a resist, smear a thin layer of colored slip over the pot. 6 Use several smaller lace sections with cuts to better adhere to the 3D form.

Next, I place small sections of lace on the surface of my vessel or another object. I do not press the lace into the surface; it is only held onto the vase with the added slip. Then, I take my index finger and load it up with a small amount of slip. With a deliberate and confident swipe, I spread the slip over the laced-covered pot, working it over the entire surface in an even layer that is as thin as I can get without harming the integrity of the pot (5). Once I have finished adding slip to all areas, I carefully find the edges of the lace and peel the lace off (6), taking with it all the excess slip that was blocked by the more detailed areas of lace. I remove the lace immediately after application—I do not let it dry. I continue with the lace technique until I cover as much of or as little of the surface as I want (7). 

7 Before the slip dries, find the edges of the lace and carefully peel to remove.

Prepping Piping Bags 

After printing with lace, I move into piping decorations. First, piping bags have to be filled. Fill one piping bag with uncolored porcelain slip, then a second bag with colored slip. 

To fill the piping bags, I use a tall, thin water bottle with the top cut off, a tall thin glass will work as well. But before we need the filling assistant, one must choose a tip and install a caliper on the inside of the piping bag with about half an inch (1.3 cm) exposed. Then, from the outside of the bag, place your desired piping tip and secure it with a washer to hold the tip in place when piping, while also allowing you to change tips fast and easily at will. I then set the bag inside of the altered water bottle with the tip pointing toward the bottom of the bottle and the widest part of the bag is in the air. Gently fold the top of the bag or the widest part over the bottle’s edges. Begin filling the bag by adding a big portion of slip, I aim for an amount that will slightly overfill my intended work area. Then I will lower the bag further into the bottle allowing you to fill the bag as full as you would like, just keep in mind you want at least 2 inches at the top so you’re able to adequately seal the bag while piping, additionally keeping pressure on the bag so that the slip is expelled at a constant rate. 

Sometimes I like to create a third bag with a marbled effect. To do this, I pipe 4–7 lines of colored slip starting the first line as far down into the bag as possible, and each additional line slightly shorter. If you have too many lines at the same depth, the effect will not look marbled. Then, I flood the bag with a white slip. These two slips must be of a very similar viscosity so that they marble. If one is much stiffer, it will cause a gummy visual texture where the two slips meet. Once the first section of the bag has been veined with colored slip and filled with porcelain slip, you can start piping. 

To maintain a marble effect when piping, offset the colored pipes of slip while also trying to randomize them so they don’t look too patterned. This will help you achieve a full trompe-l’oeil effect. I suggest using a small star tip #14, #2E, or a combination of round tip sizes and a small star tip resulting in a variation of veining. 

Frosted Vessels by Robert Chamberlin sidebar

Piping Decorations 

While most of what I do is similar to cake decorating, the slip is significantly thicker than frosting, which slightly changes the physics. It also means you need strong hands to do this work! 

Starting from the bottom of the vessel, pipe a border around the base (8). I don’t do any scoring, as the thick slip adheres well to the moist slip-cast vessel. For the bottom border, I use a Wilton tip 21 and tip 5. I have experimented with my piping tips and differing pressures and can make many different textures and marks this way—experiment to find what you like. 

8 On a banding wheel, pipe slip in rows starting at the base and working up.

Once I start piping with the slip, I am in a delicate balancing act of introducing more moisture to the piece and will use a hair dryer on low heat to aid in the vessel’s ability to stay upright and not slump or collapse. 

Adding the droops is my favorite way of piping slip at the moment. I love that I can conceal part of the lace decoration by adding more contrast to the piece. The droops start at the rim of the vase and are delicately swooped over and down. About halfway down the neck of the vase, I turn my wrist and give a continuous even pressure to the piping bag letting the slip almost reach its final depth before I bring my hands back to the rim of the vase anchoring the droop to the inside of the vase, close to where the gesture started (9). The first droop helps anchor the next one, with it starting directly attached to the previous droop. Repeating over and over until there is a droop curtain around the neck of the vase (10). Often on the rims of my vessels, I will use a star-tip bag and pipe a crown (see 11). Following that, I will add small solid-colored droops in between layers of star-tip piping (11). I continue to delicately add layers until I feel the vessel is complete (12). 

9 Using continuous even pressure, squeeze droops anchored at the rim. 10 The first droop connects to the next as you work around the pot.

11 Add variety with different tips and slip colors, building a curtain around rim. 12 Continue to delicately add layers, then tent plastic over the vessel to slow dry.

Building Tips and Finishing Touches 

The delicate nature of my work, coupled with variations in water content between the base and slip, necessitates a gradual drying process. I often create directly on a kiln shelf to decrease the number of times the piece needs to be moved and hopefully never have to touch the vase directly until it has made it out of the bisque firing. 

Once a piece has been completed, it is tented in place. I use old casting-slip containers filled with water, tall thin water bottles filled with sand, and kiln furniture to create a scaffolding to hold plastic so it doesn’t touch the piece, protecting the delicate slip frosting from losing any detail. On my next day in the studio, I move the work, while on the kiln shelf, to a drying cart that is wrapped in plastic and will dry the piece very slowly over a 1–3 week period depending on the size of the work. I occasionally use kiln furniture to prevent pieces from falling into kiln walls, but also play with the effect of slumping, as the work is often about collapse. 

Finished vessel by Robert Chamberlin

I am constantly trying to push the limit of how much I can add to a vase. Invariably, I am met with failure. This has inspired previous bodies of work and subsequent exhibitions that center on the idea of causing a vase to collapse due to the sheer weight of the decoration. 

Robert Chamberlin is a conceptual artist living and working in Atlanta, Georgia. He received his MFA from The School of the Museum of Fine Art Boston and Tufts University. To see more of his work, visit www.robertchamberlin.com or on Instagram @studiochamberlin.