Clay Extrusion

Extrusion of Plastic Clay — has for centuries been used to produce construction bricks and floor and roof tiles as well as tubular pipe and drain forms. The motive force used to drive clay extruders varies from “arm strong” to horse driven to motor propelled apparatus.

Creating custom extrusion dies “kicks the door open” to a great variety of formal choices. Die design and fabrication is fascinating but potentially demanding for more complex cross sections. 1/4 to 1/2 inch thick acrylic (Plexiglas) sheet best serves my extrusion die needs—because it is relatively easy to cut and mill and hard and durable enough to serve my modest production needs. I have plexiglas dies showing no sign of distress after 4o odd years of frequent use. I use acrylic dies on all 4 of my pug mills and would find clay life cumbersome without them. Each of my pug mills includes a simple adaptation of common PVC drain waste fittings called Male and Female Adapters. This allows me to quickly add or remove extrusion dies as need requires. Understanding and incorporating a “zipper core bridge” vastly expands die extrusion range and capability (a die aspect which I will illuminate as time permits). I find clay extrusion and die design and fabrication exceedingly entertaining engineering.

My video below illustrates one application of the above detail.