CHAPTER 12
Flower Boxes and Other Straight Forms
THERE ARE THREE WAYS TO PRODUCE FLOWER BOXES in color cement and the methods equally apply to other straight-sided objects that are to be hollow or act as containers.
MOLDS MADE FOR STRAIGHT-SIDED OBJECTS have the advantage of permitting the joints of the molds to come on the corners or junctures of the straight sides; thereby making the entire elimination of any joints remaining on the object (from where the molds come together) an easy matter of removal.
ONE OF THE WAYS TO PROCEED IN THE MAKING OF A FLOWER BOX is as follows: Take any ordinary good proportioned small wooden box, or block of wood of the right shape, and place a thin layer of modeling wax over the surface until it is smooth and evenly coated. Model the design desired on the four sides, avoiding, as has been before cautioned, having undercut or overhanging portions.
THE DESIGN MAY BE SECURED WITHOUT MODELING by taking the box and covering the sides with cut cardboard designs, the cut sections producing the motifs or the spaces between the cut and applied portions being the motifs. In either case the cut sides of the portions applied should slant so that the widest portion of any opening formed where two applied pieces come together will be widest at the top. The reason for this is to prevent locking of the plaster which will be poured over the surfaces to produce the molds.
IF THE CARDBOARD IS USED FOR THE DESIGN after the glue is dry, the entire surfaces of the portions to come in contact with the plaster is given two coats of shellac, the second coat to be given after the first coat is dry. The shellac should be permitted to dry well.
TO MAKE THE MOLDS the box with the design is turned upside-down and a mold is made of the bottom first. This is done by surrounding the four sides with wooden retaining walls so that the sides extend at least an inch above the edges. Into the space formed by the four projecting walls, plaster is poured and permitted to dry. This will result in a slab of plaster to reproduce the bottom of the flower box in the final cement casting. If legs or irregular portions are on the bottom, the mold should include these portions.
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.
THE THIRD WAY TO PRODUCE A BOX in color cement is by pouring, and the method is as follows: When making the molds instead of making the parts as usual, make a mold part for the top instead of the bottom, as the pouring mold is made upside down.
When the four sides and top portion of mold are ready, they are assembled and the metal inside mold is placed inside of the plaster mold.
THE METAL INSIDE MOLD is a metal pattern which when folded together represents the inside space of the box. Within this metal pattern or box, strips of wood or plaster should be placed to keep the metal or tin form in shape when the pouring of the cement commences. A good way to secure a perfect fitting brace inside of the metal form is shown in the working plate accompanying this chapter.
When this metal box with enclosed bars is placed in the right position within the plaster mold, the cement mixture is then poured into the spaces between the outside mold and the metal box until the space is filled. Then the cement pouring is continued until the top of the metal box is covered adding enough more to form the bottom. It will be thus seen that the metal box must be planned low enough so as to permit of a bottom space.
TO FINISH THE BOX, it is turned over after the cement has sufficiently hardened and the plaster, or wooden bar, is removed. The sides of the metal box are folded inward and the entire box removed. This will leave the inside of the box free for the smoothing or scraping of faults or filling in of bubble holes which can easily be accomplished before the cement has entirely hardened. The outside portion of the plaster mold is then removed and the flower box appears complete except for the surface coloring or finishing as may be desired.
OTHER SQUARE-SIDED OBJECTS may be similarly treated, in some instances the shapes or proportions requiring different handling. For instance, a very long narrow box could not be easily produced by rotating and should be made by the spreading or pouring method. Large surfaces or very long surfaces should be reinforced by the placing of wire cloth in the walls when the cement is poured in.
TAMPING OR PRESSING OF CEMENT is done by using cement and sand of a consistency like wet sand. This is placed into the mold and pressed firmly with a blunt stick, and a mallet can be used to tap these wooden chisels so as to press the cement well into the apertures. This results in a very firm surface and is particularly good for large boxes and containers. Care should be taken that the molds are firmly fastened together and the molds should be watched occasionally while the tamping is taking place to see that they do not spread.
TILES, STAINED GLASS AND MOSAICS may be included in the decoration of flower boxes. They should be glued firmly into position on the molds or boards forming the mold for the box. After a day or two drying the molds are assembled and the cement is poured in the usual way. The moisture in the cement will be found to soften the glue so that on removal of the molds the tiles, glass or mosaics will remain with the cement.
TO INCLUDE HANGING CHAINS, RINGS OR HOOKS in a cement box, the mold should be arranged so as to accommodate the chain or metal through it. The part or opening through which the metal passes is filled with clay or wax to avoid the running out of the cement. The molds can be held up from the table surface by a few blocks of wood or worked upon after being placed on a trestle.
COVERS TO BOXES can be made in the same manner as boxes. A single flat lid may have fewer molded parts but should have enough to permit easy release of the cement.