This quick, mess-free, space-saving means of producing slump molds expands the possibilities of handbuilding forms in the studio.
The following instructions outline how to create a simple and inexpensive slump mold to make bi-lateral three-dimensional forms.
One of the first workshops I attended as I shifted my art practice to ceramics was led by Lesley McInally, where we used thick cardboard produce box as molds for paper-clay slabs. I’ve since adapted this method to a single cardboard template, though I still use the produce boxes for support. Unlike traditional molds, cardboard slump molds create volume without pressing against a rigid structure. They are compact, inexpensive, and easy to make. A cardboard slump mold uses negative space to create a 3D form by stretching the clay downward with gentle pressure and gravity.
Cardboard templates can be symmetrical or asymmetrical, giving you endless possibilities for creative forms. You can make single parts and add to flat slabs to make wall pieces or matching pairs to make open or closed forms for functional ware or sculpture, even extending the volume with additional slabs. Once you’ve tested your template, you can recreate it using durable or permanent materials.
Designing and Scaling an Idea
Start by sketching your ideas. This vase series was ignited by an image of a Persian jug in Robin Hopper’s Functional Pottery book and a quest for gradual proportional changes using parabolas. I was aiming for a step-by-step change in height and width within each iteration.
Scale up to the desired size using grid paper for precision. For symmetry, fold the paper vertically and cut one half like a paper heart. I recommend starting with a size about 8×10 inches (20×25 cm) for the opening with 4 or more inches remaining on the template for strength.
Cutting the Cardboard and Safety Concerns
Look for thick corrugated cardboard (⅛-inch thickness will do and avoid folds for greater strength). I use Amazon boxes. Center your template on the cardboard, placing it against the grain to avoid bending. Outline it with a marker for clarity. Use a cutting board and an X-Acto knife to shallowly cut the cardboard until it’s fully released. If cutting straight lines, use a metal ruler. Label one side “A” and the reverse “B” for optimal alignment.
Using the Template
I keep 3–4 produce boxes in my studio for transporting and storing work at different stages. Ask for them at your local grocery store. If your template does not fit directly on the box, use wooden bars to support it. I used my rolling pin slab rails, yardsticks, and leftover wood trim.
Place side A up over a produce box and wooden bars for extra support as needed. Roll your slabs to about ⅜ inch (1 cm) thick ensuring each extends 1½ inches (4 cm) beyond the template’s open space. Center a slab over the template. Apply gentle pressure to add volume both lengthwise and across the width, being careful at the edges to avoid tearing. Record your movements and measurements on paper or directly on the template to replicate them for side B to reach a close match in volume. Be open to and embrace the irregularities and inconsistencies that may arise with this organic method.
After the clay firms to a soft leather hard, remove it from the template, flip it onto a plastic-lined drywall board and wrap it up. Let the cardboard template dry out before reusing it. To make side B, repeat the steps.
Trimming and Connecting the Sides
Both sides should be at the same level of firmness for the best connection. If one side gets too firm, place it in a damp box to equalize. Before you use a sharp blade to cut the excess clay away, think about the surfaces you want for the connection. For extra support add a soft coil on the interior circumference to align the two sides. Score, slip, and attach. Use a serrated metal rib to close the exterior seam. Add additional coils where needed to strengthen the exterior seam. If creating a vase, use your hands or other tools to gently expand the volume at the top and bottom to widen those areas. Smooth out the coil on the interior with a long bristle brush through the holes on each end. Score, slip, and attach a slab for the bottom. When the clay is a firm leather hard, use a rasp to refine the edges. Use a smooth rib to refine the surfaces. If making a closed form, add a pinhole to aid in consistent and even drying.
Go Beyond Bi-Lateral Symmetry
In my own work, when the connected clay form was still soft enough to manipulate, I went beyond the basic bi-lateral symmetry in three ways. I created a dynamic flow line across the surfaces by gently rubbing with a rib tool along a line and pushing it out from the inside. On another vase, I created rotational symmetry by tapping the edges into a twist. Lastly, I increased the volume of a four-sided form by attaching side slabs of the same thickness, adding depth between the main parts.
the author Jacquie Blondin is an artist, educator, and entrepreneur based in Mississauga, Ontario. She holds a BA from McMaster University and a BEd from Queen’s University. With over 30 years of experience as a visual arts teacher and 20 years working in clay, Blondin now focuses on creating functional and sculptural ceramic work in her home studio, often blending handbuilding and printmaking techniques into her process. A dedicated member of her local pottery guild, she shares her passion for ceramics by teaching classes for adults and youth, both in-person and online. Her experience in education also led to the creation of the Spin Wiper, a glazing tool designed to support potters in their craft. Blondin regularly showcases her work and creative journey on Instagram, connecting with a wider community of ceramic enthusiasts. For more, visit www.jacquieblondin.com.
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This quick, mess-free, space-saving means of producing slump molds expands the possibilities of handbuilding forms in the studio.
The following instructions outline how to create a simple and inexpensive slump mold to make bi-lateral three-dimensional forms.
One of the first workshops I attended as I shifted my art practice to ceramics was led by Lesley McInally, where we used thick cardboard produce box as molds for paper-clay slabs. I’ve since adapted this method to a single cardboard template, though I still use the produce boxes for support. Unlike traditional molds, cardboard slump molds create volume without pressing against a rigid structure. They are compact, inexpensive, and easy to make. A cardboard slump mold uses negative space to create a 3D form by stretching the clay downward with gentle pressure and gravity.
Cardboard templates can be symmetrical or asymmetrical, giving you endless possibilities for creative forms. You can make single parts and add to flat slabs to make wall pieces or matching pairs to make open or closed forms for functional ware or sculpture, even extending the volume with additional slabs. Once you’ve tested your template, you can recreate it using durable or permanent materials.
Designing and Scaling an Idea
Start by sketching your ideas. This vase series was ignited by an image of a Persian jug in Robin Hopper’s Functional Pottery book and a quest for gradual proportional changes using parabolas. I was aiming for a step-by-step change in height and width within each iteration.
Scale up to the desired size using grid paper for precision. For symmetry, fold the paper vertically and cut one half like a paper heart. I recommend starting with a size about 8×10 inches (20×25 cm) for the opening with 4 or more inches remaining on the template for strength.
Cutting the Cardboard and Safety Concerns
Look for thick corrugated cardboard (⅛-inch thickness will do and avoid folds for greater strength). I use Amazon boxes. Center your template on the cardboard, placing it against the grain to avoid bending. Outline it with a marker for clarity. Use a cutting board and an X-Acto knife to shallowly cut the cardboard until it’s fully released. If cutting straight lines, use a metal ruler. Label one side “A” and the reverse “B” for optimal alignment.
Using the Template
I keep 3–4 produce boxes in my studio for transporting and storing work at different stages. Ask for them at your local grocery store. If your template does not fit directly on the box, use wooden bars to support it. I used my rolling pin slab rails, yardsticks, and leftover wood trim.
Place side A up over a produce box and wooden bars for extra support as needed. Roll your slabs to about ⅜ inch (1 cm) thick ensuring each extends 1½ inches (4 cm) beyond the template’s open space. Center a slab over the template. Apply gentle pressure to add volume both lengthwise and across the width, being careful at the edges to avoid tearing. Record your movements and measurements on paper or directly on the template to replicate them for side B to reach a close match in volume. Be open to and embrace the irregularities and inconsistencies that may arise with this organic method.
After the clay firms to a soft leather hard, remove it from the template, flip it onto a plastic-lined drywall board and wrap it up. Let the cardboard template dry out before reusing it. To make side B, repeat the steps.
Trimming and Connecting the Sides
Both sides should be at the same level of firmness for the best connection. If one side gets too firm, place it in a damp box to equalize. Before you use a sharp blade to cut the excess clay away, think about the surfaces you want for the connection. For extra support add a soft coil on the interior circumference to align the two sides. Score, slip, and attach. Use a serrated metal rib to close the exterior seam. Add additional coils where needed to strengthen the exterior seam. If creating a vase, use your hands or other tools to gently expand the volume at the top and bottom to widen those areas. Smooth out the coil on the interior with a long bristle brush through the holes on each end. Score, slip, and attach a slab for the bottom. When the clay is a firm leather hard, use a rasp to refine the edges. Use a smooth rib to refine the surfaces. If making a closed form, add a pinhole to aid in consistent and even drying.
Go Beyond Bi-Lateral Symmetry
In my own work, when the connected clay form was still soft enough to manipulate, I went beyond the basic bi-lateral symmetry in three ways. I created a dynamic flow line across the surfaces by gently rubbing with a rib tool along a line and pushing it out from the inside. On another vase, I created rotational symmetry by tapping the edges into a twist. Lastly, I increased the volume of a four-sided form by attaching side slabs of the same thickness, adding depth between the main parts.
the author Jacquie Blondin is an artist, educator, and entrepreneur based in Mississauga, Ontario. She holds a BA from McMaster University and a BEd from Queen’s University. With over 30 years of experience as a visual arts teacher and 20 years working in clay, Blondin now focuses on creating functional and sculptural ceramic work in her home studio, often blending handbuilding and printmaking techniques into her process. A dedicated member of her local pottery guild, she shares her passion for ceramics by teaching classes for adults and youth, both in-person and online. Her experience in education also led to the creation of the Spin Wiper, a glazing tool designed to support potters in their craft. Blondin regularly showcases her work and creative journey on Instagram, connecting with a wider community of ceramic enthusiasts. For more, visit www.jacquieblondin.com.
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