A clay extrusion tool is a great way to create long strands of clay in specific shapes in near perfect consistency, ideal for projects like mille fiori. A clay extruder is a simple enough machine that you can build one on your own using a variety of materials and techniques. With a homemade extruder, you can customize the shape and size of your extruded clay shapes while saving money on the cost of crafting supplies.
Homemade Clay Extruder
The primary portion of a clay extruder is made up of a tube. You can use whatever you want for a tube, provided it's hard, smooth on the inside and of the right size with a circumference big enough to incorporate the shapes you want to extrude. Good choices include plumbing pipe, old marker tubes and PVC pipe. The latter is especially good for fashioning an extruder because it's easy to customize it with screw-on caps that are ready-made and available wherever the pipes are sold.
Next, your extruder needs a plunger. The plunger of the extruder acts to regulate the flow of the clay; without it, you can push the clay through with your fingers, but the extruded clay will be uneven and unattractive. The plunger should be the same shape as the outer tube and big enough to just fit inside. The best way to make one is to cut a disk of this size from hard craft plastic or metal, then glue a plunger to the back of it. The plunger can be made from a pencil, dowel, or any straight, hard stick that's long enough to handle even when it's been stuck all the way through the extruder pipe.
The shaping plates are the most important part of the extruder. This is where some real craftsmanship is required. You can use store-bought shaping plates with a homemade extruder, provided they are of the right size, or you can make your own. Use hard metal or plastic and draw the shapes you want to extrude in permanent marker, then cut them away using a rotary cutter with a fine cutting or grinding attachment. (You can cut the shapes through other means, but a fine power tool point like this will give you the best look.)
Once you have discs, secure them to the end of the pipe and your extruder will be ready to use. If you're using PVC pipe with a threaded end, get a screw-on end cap, then cut away the inside circle of the top of the cap. Place the disc on the end of the pipe before screwing the cap in place.
With other types of tubes, you can secure the discs using a piece of leather. Cut away a circle from the leather and place that hole over the disc before wrapping the leather around the end of the pipe and securing it in place with a rubber band.