Color Cement Handicraft

by Pedro J. Lemos; Reta A. Lemos

As soon as this bottom section is hard, the keys are bored into it and one of the sides is next molded. When molding the sides, turn the model so that the plaster is poured onto the sides and not so that it is poured alongside the surface. This is done by turning each side to be molded so that it is horizontal or flat.

WHEN ALL THE MOLDS ARE MADE and dried they are ready for casting the cement box. They should be placed in water until all parts have absorbed moisture. Next they are oiled well and assembled. If more than one color is to be used, the molds for those sides to have color should have the color cement placed on the molds while the surfaces are flat. When this color has set sufficiently to permit the sides to be placed upright, without the color running, the sides should be assembled with the bottom mold and the whole set tied together ready for the pouring of the cement.

THE FIRST MIXTURE OF CEMENT should be a thick mixture, just as thick as will run easily when the mold is rotated. The first mixture of cement should be of neat cement and may have color mixed with it. It is poured into the mold or placed in with a spoon, and the mold is rotated slowly until the mixture has covered all the inside surfaces. The surplus, if any remains, is poured out from one of the corners.

THE SECOND MIXTURE OF CEMENT should be poured in after the first layer has set. This usually takes from an hour to half a day depending on climatic conditions. The second mixture should be of sand and cement and of a thinner mixture than the first. This is necessary as the first layer will absorb moisture very rapidly from the second layer and therefore it should be very thin.

THE LAST LAYER OR MIXTURE should have color in it also and is added in the same manner as the second mixture, after the previous layer has set. This is the finishing layer and the color should be arranged to be in harmony with the outside color. A harmonious color will be one that is a lighter value of the outside color or it may be color that is complementary to the outside color.

THERE ARE TWO IMPORTANT THINGS TO REMEMBER in making pottery or boxes where the molds are rotated. One is that the mold to be rotated should not be shellaced. The reason for this is that the plaster molds must absorb some water from the cement mixture to produce the thin lining or inside coating. The second thing to remember is to pour the surplus mixture in the second rotation from the side opposite that the first surplus mixture was poured. As the lining is inclined to be thicker where the pouring out occurs, using an opposite side for the second pouring out will equalize the lining of color.

THE SECOND METHOD TO PRODUCE A FLOWER BOX is by spreading the color in the mold with a knife, pressing it up against the sides with a palette knife or small trowel. This is possible because the opening is large enough to permit seeing the sides. Where the opening is small such as that in a vase or jar with tapering sides it cannot be done this way and the method of rotation must be relied upon.

WHEN SPREADING THE COLOR CEMENT or lining, the mold should be turned so that as the mixture is placed and spread a flat surface is being worked upon. This makes it easier to work and insures the cement adhering to the mold. After the sides are fully covered, a thin mixture may be poured into the bottom and this whole mixture (the bottom and walls) permitted to harden.

IF DRAIN HOLES ARE NEEDED in the bottom of the flower box, two cylinders of clay or modeling wax may be placed upright in the bottom of the mold. These cylinders should be long enough to protrude above the bottom layer of cement that is poured in, and after the cement layer has hardened, they may be removed. This is preferable to endeavoring to drill the holes out of the bottom after the box is removed from the mold which might result in breaking the entire box.

AFTER THE BOX IS ENTIRELY DRY it may be given a gasoline color wash or rubbed with a thin color cement wash and after the color has become partly dry, the surplus rubbed off with a cloth. A wax rub given with a soft cloth and floor wax afterwards will smoothen up the entire surface producing a velvety surface.