Color Cement Handicraft 14
SMALL SECTIONS OF GLASS can be better separated after the glass cutter
has been used if small pliers or dull nippers are used to grip the
glass. Hold the largest piece of glass firmly between the fingers and
with the nippers grip the glass close up to the line of division and
with a quick downward turn of the nippers it will divide the glass along
the line produced by the cutter.
The sections of glass when all cut may be trimmed to truer forms by
using a corborundum stone or file.
AFTER THE GLASS HAS BEEN CUT, place a tracing upside down on the table
and a glass over the tracing. The tracing on the underside of the paper
should be visible through the glass, and of course is reverse in
position. Take each piece of glass and touch the right side with glue
and place it onto the glass over its location defined by the tracing.
Assemble all the glass in this way, all the pieces being glued face
downward onto the glass. Mother-of-pearl, metals, etc., can be assembled
the same way, and the fact that they are thinner than the glass need
make no difference as their surfaces all resting upon the glass will
result in their being all the same level on the completed tile.
THIRD STEP: POURING THE CEMENT. After the glass has been glued and left
remaining for several hours (to permit the glue to dry) the retaining
bars are placed on the glass, at the proper distance from the cut
sections and cement is then poured into and over the glass mosaics until
the required thickness of tile is secured. This mixture may be color
cement or the neat Portland cement, care being taken to pour it in
slowly from the center to avoid formation of bubbles.
FOURTH STEP: FINISHING THE TILE. When the tile has set for several days
it may be removed and an incised line made around the edge of each glass
mosaic. Place the tile in water to harden for several days. Remove and
let dry, then give the entire surface a gasoline wash of gray or other
color. A slight polishing of the surface will finish the tile. It will
be found that the moisture has softened the glue so that the whole tile
releases from the glass surface. The cement should be rubbed off of any
of the glass parts if it has encroached until the entire edges of the
glass mosaics are visible. This should be done before the tile is placed
in the water to harden.
[Illustration: Mosaic Tile Method]
[Illustration: Mosaic Tiles]
[Illustration: Mosaic Stone Tiles]
[Illustration]
CHAPTER 12
Flower Boxes and
Other Straight Forms
[Illustration]
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.
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