The following instructions outline how to create a simple tool to easily cut out a variety of circle sizes for plates and other items.
A number of years ago I picked up a book titled Tulip Ware of the Pennsylvania-German Potters, which had several pictures of potter’s tools used in the late 18th and early 19th centuries. As I looked at them, there was one that stood out to me as an oddball. It stated it was a “disk cutter” and it made me curious! It was a square stick about 12 inches (30.5 cm) in length with a 3-inch (7.6 cm) octagonal shape attached near the end. At the other end, there was a pointed object, most likely a nail, pressed through a hole that had been drilled into the stick. It was an unassuming tool used to repeatedly cut out a specific-sized circle shape from a clay slab. Slabs would be rolled out and the disk cutter adjusted to cut out the desired size of disk needed to make an appropriately sized pie plate. As I was looking at it, it made perfect sense and seemed to me to indeed be a useful tool. So, one afternoon in my studio using some bits and pieces, I assembled my version of this tool.
The disk cutter tool helps me to easily get repeatable circles in a wide variety of sizes all with one tool. Also, as I have begun working larger, it is harder to find objects to help me create a circle large enough for my circular bases. This tool can be made in a variety of ways, so please improvise with what you have in your studio. I made this in two different ways with slight modifications depending on what I had available (1).
Cutting the Disk and Arm
Cut out a 2½ inch (6.4 cm)–3 in. (7.6 cm) disk from ó inch (1.3 cm) plywood. I wouldn’t go smaller than a 2½ inch (6.4 cm) disk because you will need to grip your fingers on the disk while pivoting the arm. For the arm, cut a length of wood from a 5/8-inch (1.5-cm) square dowel that suits your needs for your circle shape. I also made a version of this using a paint stick from the hardware store that had a ruler on it, which was nice because it is thinner and already cut to an appropriate length.
Remember two things:
The length of the arm is the radius (not the diameter) of your circle. Therefore, the arm length needs to only be half as long as what you want the circumference to be for your circle.
The longer your arm, the bigger area you need to make your arm go in a full circle. I have found an arm larger than 12 inches (30.5 cm) makes a disk larger than I can fit in my kiln. I recommend an arm length of 8–12 inches (20.3–30.5 cm). For my arm, I cut a 12-inch length (30.5 cm) (I also have a little overhang for where the screw goes in).
Arm Measurements
Before you attach the arm to your wooden disk, you will need to mark out the holes where you will insert your needle tool to cut out the appropriately sized circle. I used a quilting ruler to help mark out the holes (2). I marked a hole every ½ inch (1.3 cm), which will result in 1-inch (2.5-cm) variants of a circle. Once the measurements were drawn on, I clamped down the arm on another piece of scrap wood to ensure that as I drilled through the arm, I didn’t ruin my table, and it helped stabilize the arm while drilling. Using a 3⁄32 drill bit (which is the right size for my needle tool to fit through) I drilled a hole every ½ inch (1.3 cm) down the center of the arm (3). Be sure to mark the measurements of your holes from where your pivot arm screw is placed, not the end of your wood length to give you accurate measurements.
Attaching the Arm
There are two ways to attach your arm to your disk.
1. The first is the simplest: about 1 inch (2.5 cm) from the end of your arm, using a slightly larger drill bit, widen a hole to be slightly larger than your screw width, this is where you will attach your arm to the wooden disk (4). This hole needs to be slightly larger than your screw so the arm can swivel around. Find a screw (in this case I used a 1-inch (2.5-cm) long round-head screw) thick enough to go through both pieces of wood without penetrating the lower disk. Locate the center of your wooden disk and drill a pilot hole. Next, place the arm on top and line up your slightly larger hole on the arm with the centered hole in the disk. I placed a washer between the screw and the wood to keep it from compressing too much. Using your screw and washer attach the two together (5). There should be enough room in the hole in the arm so it can pivot easily.
2. The second way is to use a drill bit with a counter sink (see 6). This is a little cleaner and you don’t have to worry about the screw poking into your clay. Drill a centered hole in your wooden disk with the countersink slightly larger than your screw. For this method, place your arm down first and align your wood disk with the arm giving a slight overlap. Screw in your arm from the disk side and don’t attach it snugly, allow for a slight wiggle so the arm can pivot around.
Using the Disk Cutter
To use your disk cutter, roll out a slab of clay (7), and place the disk cutter in the center. With one hand placed on the wooden disk, place your needle tool in the appropriate hole for your desired measurement and pivot the arm around the circle using your other hand to hold down the center disk while the needle tool cuts out the disk (8, 9).
With this tool, I no longer need to have a bunch of paper templates around my studio, it can operate as a ruler and template all in one. Also, it’s big enough that I can keep it with all of my other tools and not lose it.
the author An artist and associate professor, adjunct at the School of the Art Institute of Chicago, Emily Schroeder Willis, received her BFA from the University of Minnesota, Twin Cities, and her MFA from the University of Colorado Boulder. Growing up in Minnesota, she was strongly influenced by Japanese Mingei traditions, while also being inspired by her mother’s upbringing in a Mennonite community. Presently, she is using the history and language of historical vessels to reevaluate the pictorial landscape and the spaces that women occupy. To learn more, www.emilyschroeder.com.
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The following instructions outline how to create a simple tool to easily cut out a variety of circle sizes for plates and other items.
A number of years ago I picked up a book titled Tulip Ware of the Pennsylvania-German Potters, which had several pictures of potter’s tools used in the late 18th and early 19th centuries. As I looked at them, there was one that stood out to me as an oddball. It stated it was a “disk cutter” and it made me curious! It was a square stick about 12 inches (30.5 cm) in length with a 3-inch (7.6 cm) octagonal shape attached near the end. At the other end, there was a pointed object, most likely a nail, pressed through a hole that had been drilled into the stick. It was an unassuming tool used to repeatedly cut out a specific-sized circle shape from a clay slab. Slabs would be rolled out and the disk cutter adjusted to cut out the desired size of disk needed to make an appropriately sized pie plate. As I was looking at it, it made perfect sense and seemed to me to indeed be a useful tool. So, one afternoon in my studio using some bits and pieces, I assembled my version of this tool.
The disk cutter tool helps me to easily get repeatable circles in a wide variety of sizes all with one tool. Also, as I have begun working larger, it is harder to find objects to help me create a circle large enough for my circular bases. This tool can be made in a variety of ways, so please improvise with what you have in your studio. I made this in two different ways with slight modifications depending on what I had available (1).
Cutting the Disk and Arm
Cut out a 2½ inch (6.4 cm)–3 in. (7.6 cm) disk from ó inch (1.3 cm) plywood. I wouldn’t go smaller than a 2½ inch (6.4 cm) disk because you will need to grip your fingers on the disk while pivoting the arm. For the arm, cut a length of wood from a 5/8-inch (1.5-cm) square dowel that suits your needs for your circle shape. I also made a version of this using a paint stick from the hardware store that had a ruler on it, which was nice because it is thinner and already cut to an appropriate length.
Remember two things:
Arm Measurements
Before you attach the arm to your wooden disk, you will need to mark out the holes where you will insert your needle tool to cut out the appropriately sized circle. I used a quilting ruler to help mark out the holes (2). I marked a hole every ½ inch (1.3 cm), which will result in 1-inch (2.5-cm) variants of a circle. Once the measurements were drawn on, I clamped down the arm on another piece of scrap wood to ensure that as I drilled through the arm, I didn’t ruin my table, and it helped stabilize the arm while drilling. Using a 3⁄32 drill bit (which is the right size for my needle tool to fit through) I drilled a hole every ½ inch (1.3 cm) down the center of the arm (3). Be sure to mark the measurements of your holes from where your pivot arm screw is placed, not the end of your wood length to give you accurate measurements.
Attaching the Arm
There are two ways to attach your arm to your disk.
1. The first is the simplest: about 1 inch (2.5 cm) from the end of your arm, using a slightly larger drill bit, widen a hole to be slightly larger than your screw width, this is where you will attach your arm to the wooden disk (4). This hole needs to be slightly larger than your screw so the arm can swivel around. Find a screw (in this case I used a 1-inch (2.5-cm) long round-head screw) thick enough to go through both pieces of wood without penetrating the lower disk. Locate the center of your wooden disk and drill a pilot hole. Next, place the arm on top and line up your slightly larger hole on the arm with the centered hole in the disk. I placed a washer between the screw and the wood to keep it from compressing too much. Using your screw and washer attach the two together (5). There should be enough room in the hole in the arm so it can pivot easily.
2. The second way is to use a drill bit with a counter sink (see 6). This is a little cleaner and you don’t have to worry about the screw poking into your clay. Drill a centered hole in your wooden disk with the countersink slightly larger than your screw. For this method, place your arm down first and align your wood disk with the arm giving a slight overlap. Screw in your arm from the disk side and don’t attach it snugly, allow for a slight wiggle so the arm can pivot around.
Using the Disk Cutter
To use your disk cutter, roll out a slab of clay (7), and place the disk cutter in the center. With one hand placed on the wooden disk, place your needle tool in the appropriate hole for your desired measurement and pivot the arm around the circle using your other hand to hold down the center disk while the needle tool cuts out the disk (8, 9).
With this tool, I no longer need to have a bunch of paper templates around my studio, it can operate as a ruler and template all in one. Also, it’s big enough that I can keep it with all of my other tools and not lose it.
the author An artist and associate professor, adjunct at the School of the Art Institute of Chicago, Emily Schroeder Willis, received her BFA from the University of Minnesota, Twin Cities, and her MFA from the University of Colorado Boulder. Growing up in Minnesota, she was strongly influenced by Japanese Mingei traditions, while also being inspired by her mother’s upbringing in a Mennonite community. Presently, she is using the history and language of historical vessels to reevaluate the pictorial landscape and the spaces that women occupy. To learn more, www.emilyschroeder.com.
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