Below are a few photos from my experiment last week. For the mashed potato flakes I used about 1/2 cup potato flakes to 1 cup hot water. For the dextrin, I used about 1 1/3 cup dextrin to 1 cup hot water. I spread the paste on with a squeegee and used the sgraffito technique to scratch into the wet paste. After the paste had dried, I applied thickened dye.
This shows the mashed potato flakes using the sgraffito technique. I scratched into it with a bamboo skewer and placed a lace doily, bubble wrap and a rubber rug gripper on for texture.
Another example of mashed potato flakes applied with a squeegee.
This is potato dextrin, applied with a squeegee and then I embedded objects in the moist paste to create pattern and texture. I didn't get the nice crackling I expected, nor much patterning, but I blame my impatience. I applied the dextrin while it was still hot. It needs to cool somewhat before using so it thickens properly. It went on as a very thin coating, which didn't crack much when dried.
This is also potato dextrin. I stamped it on and applied it with a brush. I had forgotten how well it works as a resist when stamped onto the fabric.
I am currently doing some fat quarter studies, layering different resist techniques. This is one of the studies using potato dextrin. I brushed the dextrin through a large plastic grid. I left the grid on until the dextrin had partially dried. Very interesting! Today I'll work on the next layer of color.