How to Use Tar Paper as a Support While Slab Building Tar paper is a great material to use for templates for handbuilding! Jonathan Kaplan

Tar paper is a great material to use for templates for handbuilding, but Lisa Pedolsky takes this idea one step farther by using tar paper as support while constructing the piece. This way she can work with clay at a variety of stages and not worry about it collapsing.

In today's post, Jonathan Kaplan explains Lisa's entire slab building process for her "Arrow Jars" from the beginning sketches to creating a functioning lid and flange. - Jennifer Poellot Harnetty, editor

Ceramic artist Lisa Pedolsky spent her formative years as a student at California College of the Arts and had no idea of how her career in clay would develop. After graduation she pursued other art interests in mixed media and book arts before returning to ceramics when she realized "clay is the heart piece" that was really missing. Pedolsky understood that she was a handbuilder, a designer, and constructor of objects.  

While Lisa likes to think of herself as a sculptor, even though she makes functional forms, she does not think of herself as a potter but as an artist working in clay. As a designer, by the fact that her work is hollow, function becomes attached to the piece. Her work deals with the challenges of working as designed, both aesthetically and technically. Everything about her work stems from intention. For example, glazing and surface decoration are not afterthoughts; they play as important a role as the design and constructing the work. Surface and form receive the same thoughtful consideration. A perfectionist with attention to detail, she does not want her work to look like anyone elses. She quips, "When you do what you always have done, you always get what you have always gotten."

The Arrow Box Method

Lisa has developed a systematic way of making her pottery, and she likes the analogy of the sewing process where the inside of a garment is as important as the outside. Her handbuilding technique follows a pattern-making process. She looks at each piece as a series of three-dimensional planes in space.

Templates to Construction

All of Pedolsky' work begins as a sketch on paper. She sees the potential for each piece in the drawing. Working first with sketches, she then develops a technical drawing from which the patterns are taken (figure 1). From these patterns, she designs and constructs forms that are highly structured with an architectural reference. The initial sketch establishes a profile and a sense of scale and mass.

The Arrow Box is ten inches high and six inches in the other dimensions. Using soft pencils, she refines the sketches until they make visual sense. She can spend weeks, often months refining the concept. Once the sketches are fully articulated, Pedolsky designs 2 - 3 pieces as a small series of works and takes 1 - 2 days to prepare the full-scale drawings and make the patterns.

She checks everything to make sure that the proportions are correct before moving to the clay slab with tar paper or simple paper patterns (figure 2). "The beauty of using tar paper," says Lisa, "is that the clay can be worked at any stage, soft wet slabs or stiff leather-hard slabs."

Lisa uses a mid-weight tar paper for most of her working patterns (figure 3). The slab can be any consistency as the tar paper becomes the exoskeleton for the form. If she is using paper patterns, her slab is prepared a day before. She rolls the slabs with a slab roller leaving them thicker than needed. The slab is compressed on both sides and in every direction using a flexible rib. The rib also removes any texture imparted by the canvas sheets from the slab roller. To further refine the slab thickness to what she likes to work with, Lisa uses a rolling pin with wood dowels on each side of the slab to determine the appropriate thickness. The slab’ thickness is finally checked with a needle tool. Comments Lisa, “I give the slabs some serious compression in as many ways and directions as I can.”

Once the slab is ready, she moistens each tar paper template. The patterns are positioned on the slab and, using a pizza roller or brayer, she pushes down to make the tar paper flush with the surface of the slab (figure 4). Since all the components are made from the same slab, the shrinkage is uniform throughout the piece. Lisa then uses a dull X-Acto knife to accurately cut the clay. She also ribs the back of the cut pieces to further compress each part thoroughly (figure 5). At the same time, she cuts a long slab from the remaining slab for the lid flange and uses the balance of the slab to form the bottom of the Arrow Box. These pieces are put under plastic for later use.

Assembling the Body

Lisa begins the assembly of the Arrow Box by cutting a shallow bevel on the long edges so that the seams can be further compressed after assembly (figure 6). No clay coils are used at any of the seam junctures, nor does she use a sponge at anytime during the construction of this piece. After scoring the edges and applying a simple slurry of her clay body and water, she attaches all four sides of the box leaving the tar paper in place to support the box during its construction.

The assembly of all her slab components involves scoring the edges, using slip to help the joinery, ribbing the joints together, and finally paddling the seams (figure 7). The slab components become firmly wedded to each other. After the initial assembly of the four sides, she uses a light-weight paddle on the seams. The excess clay moves into the joint as she paddles the corners. She stops when the edges of the tar paper meet. The piece is then moved onto foam for support.

Using a finger, Lisa removes any excess slip that has been forced from the seams on the inside of the box. Then using a dull, soft pencil point and a plastic drawing triangle as a guide, she creates a rounded ditch
or trough and gently compresses the inside seam from top to bottom (figure 8). This small detail creates a design element that, provides a place for the glaze to pool and highlight the interior seams. Once the exterior walls are assembled and squared up, the bottom surface is sprayed with water, covered with plastic, and the piece is put aside.

Fitting the Top

With the four triangle sections already cut, Lisa measures the outside dimensions of the top of the body that has just been constructed. She then draws this square shape on her worktable and prepares to assemble each piece. After cutting a soft bevel, the edges are moistened and pressed together. The bottom edge corresponds to the square perimeter she has just drawn (figure 9) and the four top pieces go together in a logical sequence by drawing them together as pieces of a puzzle. Using a paddle with a thick edge, she squares up the top so it lines up with the drawing on the table again (figure 10).

The four angled seams are paddled together, compressing and forcing the joining slip to the inside of the truncated top. Finally, turning the piece upside down, she cleans the inside seams with her fingertip. Again, she uses a dull pencil to heal the inside seams and leave a small trough as a design element. Scoring the bottom surface of the top as well as the top surface of the body, she joins the pieces together (figure 11) and paddles them to form a secure and well-compressed joint (figure 12). After a final paddling, the assembled piece is put aside to dry slightly.

Joining the Bottom

Lisa begins working on the bottom of the body by inverting it onto a piece of foam. She takes a square piece of paper that is larger than the bottom and folds it into quarters and marks the folded lines with a pencil. After wetting the edges of the body' bottom, she centers the paper on the opening and presses down to get an imprint of the shape (figure 13). She cuts the paper to the same size as the bottom of the piece, wets both sides of the pattern so that it does not curl and places it pencil side down on a scrap slab. Using her pizza roller, Lisa rolls the paper flush with the clay surface. Removing the paper pattern, she affixes her "bullseye" chop or stamp and with a dulled soft pencil, lightly scores the pencil lines that have transferred to the clay. The edges of the body are slipped and scored as are the inside perimeter of the bottom slab and the slab is eased onto body and pressed down so that it conforms to the undulating shape of the base. Excess clay is trimmed with a knife (figure 14). At this time, the tar paper can be removed.

To finish and secure the bottom, the edges are first worked with a rib, then rolled so that some clay moves onto the sides of body and finally paddled. Squaring the sides up with the paddle, any remaining high points in the area can be taken down with a Surform rasp (figure 15). She finishes the construction by using a plastic rib on the seams and then gives them a final paddle to fully compress and knit them together.

Fashioning a Lid and Flange

The piece is placed right side up on a piece of foam and all the seams are again pressed in with a rib and then paddled. This extra step insures that all the joinery is uncompromised. To make the lid and the flange, Lisa uses a flexible ruler to measure from a flat plane up each of the four sides, marks the corners, and then connects the - dots. - The lid is cut at 90 degrees with two passes of a sharp X-Acto knife (figure 16). After removing the lid, she checks the interior seams and uses a blunt pencil to compress the clay and cleans up any excess clay scraps from the interior with a soft brush.

The thickness of the flange is subjective. Using the long slab originally cut from the larger one at the start, she uses a rib or a roller to arrive at an appropriate thickness. She then bevels one edge of the long slab (figure 17) and decides on the total width of the flange, how much of it will be attached into the lid, and how much projects into the body. The slab is then cut to the correct width. Lisa scores and slips around the inside perimeter of the lid and the beveled edge of the strip, and carefully attaches it to the interior of the lid starting at the center. Compressing as she attaches the bevel edge, the sections are overlapped at the end and cut at an angle for a perfect match (figure 18). Using her blunt pencil again, she seals the two adjoining surfaces together. She uses a rib and finger to carefully align the flange so that its surface matches the angles of the walls of the jar (figure 19). Once the clay construction is finished and the piece set up to what Lisa refers to as – cheese-hard, – she begins the process of decorating her pieces. Pedolsky is a master at what she does. Drawn to lidded containers, her unique construction and decoration techniques leave little to chance. The architectural sensibilities are very evident but the construction details are hidden. For Lisa Pedolsky, “function is the doorway, discovery is the goal.”

Lisa Pedolsky lives in Durango, Colorado where she owns Two Fish Studio. To see more of her work, visit www.lisapedolsky.com.

Jonathan Kaplan has worked as a potter, moldmaker, ceramic designer and manufacturer, author, and educator for more than 40 years. He currently curates Plinth Gallery (www.plinthgallery.com) and works as a ceramic artist in Denver, Colorado.

**First published in 2015.