Sunday, January 8, 2023

Extruded Forms, Glazed & Finished: Fall 2022

Extruded sculpture, horse hair raku fired, by Yarelli Sanchez

An extruder is a tool that forces wet clay through a die to create long tubes or lines of clay in that shape. I have students use this tool on the second day of hand-building class to make mugs. They use a hollow cylinder die to create hollow cylinders which form the walls of the mug. Some students are assigned to the wall extruder, while others roll slabs for the bottom of the mug. Still other students use a small hand held handle extruder to shape uniform handle blanks to attach to the extruded cylinder.

extruded chia pet stonehenge (before chia seed application) by Julia Snow

Later, students are given access to several extruders and lots of dies to create their own sculpture. They can extrude hollow cylinders using the same die they used for the mugs or they can use a smaller hand held extruder (one that looks like a caulk gun) to extrude smaller hollow cylinders. 

Yarelli's sculpture, the rings on top are slices of the extruded cylinders

Once the cylinders are extruded, they can keep them tall like the mug, or cut them down. Yarelli used both tall cylinders and cylinders cut into small rings to create her horsehair raku fired sculpture of towers and chains.

detail of Julia's extruder forms, showing carved texture

Using the large hollow cylinder die, the extrusions can be fairly thick, meaning students may choose to carve into the thick walls of the cylinders to reduce the weight and add decorative texture. To make the walls of a cylinder thinner, students can use a larger interior die or they can stretch out the extrusion by rolling a dowel inside or by manipulating it with their hands. 

extruded hand by Carlos Garcia Alcantar

After the forms are extruded, the clay is still soft, so students can choose to squish, cut or bend the extrusion or attach different extrusions together. Sometimes the extrusions bend or curve as they come out of the extruder. Students can adjust the die placement or hold the extrusion as it comes out to avoid this, or they can embrace the curve as it happens. They can even adjust the die so that these curves are more likely to happen.

Extruded sculpture by Brooke Mason


Carlos combined larger and smaller extruded cylinders to make his hand. He left the fingers more or less as they came out of the extruder, but altered the large extrusion by flattening it to create the palm of the hand. Brooke did perhaps the most altering, using extruded cylinders as the basis of her stacked anemone-like forms, but she used pinch methods to significantly alter the shape of the extrusions.

extruded hand by Carlos Garcia Alcantar

Cylinders aren't the only shapes or forms that can be extruded. Our studio has a bunch of options for solid and hollow extrusions with the 4" diameter extruder and the smaller 1" diameter extruder, but we also have an expansion box that can be used on the 4" wall extruder to stretch out the clay into larger extrusions. Artists can also make their own extruder dies by cutting metal or wood or by printing their own designs. The YVC clay studio just purchased a couple of new 3D printed extruder dies we hope to put to good use this winter.

Extruded Robot by Thai See (@thaiidraws on Instagram)

Students in the fall class used a lot of cylinders, but also a few other forms. Thai used a square hollow die to create the body, head, and legs of her robot and she and several other students extruded coils or solid cylinders that were incorporated into their sculptures.  

Extruded teapot in the style of Ray Bub by Jordan Golob

Some artists, when working with coils, prefer to extrude their coils so they are uniform. Whether rolling coils by hand or setting up and using the extruder is more labor intensive may be up for debate, but I know some folks prefer their coils extruded. Jordan used coils both decoratively and as building elements to create her extruded/coiled blue form above. 

Extruded Robot (back) by Thai See

Both Thai and Jordan used the square hollow extruder for parts of their forms. Thai chose to alter her square leg extrusions to make them narrower where they attached to the body of the robot.

horned and antlered vases by a Fall 2022 student


Lots of people like to use an extruder to create uniform handle shapes, but handles don't show up as often in sculpture. One student, who chose to remain anonymous here, chose to used the handle extruders to create a vareity of different horns and antlers on a set of extruded vases. 

surfer on an extruded wave by Amanda Goodrich


One of the unusual dies I like to see students use is an extruder die that looks like a wiggly line. When students use it, it creates what appears to be a slab with a zigzag built in. Amanda used this slab-like extrusion to create a solid wave of water for her surfer guy. She chose a copper glaze in an oxidation firing which highlights the texture pools at the bottom of the wave with an oceanic color.

Pegasus by Thunder Morales

Thunder's pegasus also utilizes the extruded wave/slab/zigzag form. In the Pegasus's case, the wave makes up the wings. Thunder also used hollow extrusions for the body, legs, and head of the mythical creature. This sort of standing form on 4 legs worries me because the legs can dry faster than the body, resulting in cracks or collapse. 

Pegasus from the front

However, the extruder turned out to be a great tool for this form because the legs and body started hollow and started structurally sound. Thunder was able to focus his time and effort on shaping the face and creating the mane and tail, rather than on balancing the form so it wouldn't fall.

Cats and Coyotes by Amy Matson

Amy's wall hanging sculpture of cats and coyotes includes 3D printed, slabbed, and extruded elements. She used the extruder in the shape of a coyote to extruded most of the tiny creatures walking along the sides of the sculpture. This die has always mystified me a bit, because it only works if you plan to extrude a long tube in this shape, then cut it into lots of flat pieces where you can see the shape. 

Trick Teapot by Amy Matson

Amy's other extruded form was her trick teapot with bamboo. The bamboo decoration, as well as the bamboo handle and spout were made from hollow extrusions, but so was the body of the form, which actually has two containeed sections that we can't see, as their openings are quite small and hidden in the bamboo.

It's often difficult to tell scale in photos on a website, especially ones without references. Amy's teapot is fairly small, more or less regular teapot size, while Thunder's pegasus is fairly large. But the winner as far as scale is certainly Derek's ancient robot relic sculpture.

Ancient Robot by Derek Arneecher

Derek used the extruder to create quite a lot of material. He had a plan going in and pretty much stuck to that plan until it came to the firing. As I explained in a previous post, Derek's sculpture had a fatal flaw, a closed hollow section in the middle, which caused it to explode during the firing. Since it was a large sculpture to begin with, it made a large mess in the kiln, but I was very pleased by how he finished the form after firing, with epoxy and acrylic paint. He chose to highlight the cracks and make them part of the story of this ancient robot form.