Paperclay and Inclusions - Part 4

This may be the first time some people have seen this material (top picture). Rice hulls, also called rice husks is the outer covering of the rice grain. Once this is removed, you have white rice. It took me a while to track this down. Finally I found it at a local feed store. It comes in a 25 lb. bag, is used as bedding for horses and it not expensive.

For my hand-pinch bowls, I wedge the rice hulls into my paperclay. How much to add? If you want more texture, add more rice hull. Use less for a subtler effect. There should still be enough paperclay to hold everything together. You will know it if what you make does not hold up. In that case, add in more paperclay and wedge till the rice hull is evenly distributed in the paperclay. You can also press the rice hulls onto the outside surface of your form but this will give a different kind of look/texture.

This material gives a VERY delicate texture (the second picture is the couples cups on its stand, the bottom picture is a close up shot of the texture) so I opt to use oxides instead of glazes. A heavy application of red iron oxide give a very grayish gun metal color in Cone 10 reduction firing. I often use this oxide to contrast against a lighter colored glaze which I use for the inside of my hand-pinched forms.

In addition to creating interesting textures in paperclay, you can also use the rice hulls as a organic combustion source for your raku post-firing reduction.

Happy experimenting!

Perlite and Paperclay - Part I

I've used several type of inclusions with my paperclay. They range from sawdust, wood chips, straw, rice hulls, and cooked rice. Recently I had a chance to try perlite mixed with my paperclay. Perlite is an inorganic material that is used as a conditioner to improve the aeration and water retention properties of soil. I got my bag of Perlite from Home Depot in the garden department. In this test, I was curious to see what the voids look like after the bisque fire.

The picture on the left shows a simple pinch form made from paperclay mixed with perlite. The amount of perlite used is just an estimate; enough to give some kind of texture. It survives the bisque fire without any problems. The form is extremely light. After sanding the outside surface of the form with a metal rasp, the random voids can be seen.

Compare this with the sphere on the right side (it's part of a sculpture I'm currently working on). It this piece, I used paperclay mixed with cooked rice. The mixture was applied as a thin coat (about 3/8" thick) over a bone dry paperclay sphere using paperclay slip as "glue." Many more regular shaped voids can been seen all over the bisqued surface of the sphere after sanding.

I was hoping to see more irregular voids from the perlite. I do see that some of the perlite still remains trapped in the bisque ware. I find the perlite from the bag is more varied in size, some ranging from size of coarse sands to around 1/4" in diameter.

I want to take both of these to high fire (cone 10 reduction) and am curious to see how the perlite behaves. I know how the paperclay mixed with cooked rice will behave as I have been using this technique for several years. I'll post another entry in the blog once I have completed this test.