"Sculpting" Mortar Recipe -- Cement Clay
Current formula for "sculpting mortar" -- 10 parts sand 6 parts clay dust 2 parts Portland cement 3 parts builder's lime This mix is light and malleable and has held up well for me outside. I sometimes add a little joint compound or asphalt emulsion. I generally mix the dry ingredients in a cement mixer and store it in five gallon buckets. I'll mix a few cups at a time with water. I mix it very damp but clumpy. I'll dip my gloved hand in water and massage a palm full of the mix, which becomes wet and malleable very quickly. When I thought of adding clay to an earlier recipe I searched for "powered clay," and local shops didn't know what I was talking about. I found clay dust online sold by the bag at The Ceramic Shop in Pennsylvania. I get builder's lime at a supplier for concrete products. I cover the work with wet towels and plastic bags to reduce the little hairline cracks that can form as mortar dries. I've been staining some of t...