Color Cement Handicraft 18

Color Cement Handicraft 18

CHAPTER 16

 

Surface Finishes

 

[Illustration]

 

 

COLOR CEMENT TILES ARE SURFACE FINISHED generally after they are dry. As

the tiles or pottery dry a lime or white powder dries on the surface and

the colors appear to become dull. To bring out the colors and remove

this powder, a soft cloth or soft brush is used to brush or dust off the

tile surface thoroughly.

 

AN OIL RUB can be given to the surface of the tile with raw linseed oil

on a soft cloth, and a brisk rubbing of the cloth will give a soft dull

polish. This should be done only on the cast and dull finish tiles and

not on the slip-painted or glazed surfaces.

 

A THIN SHELLAC COATING may be given a color cement tile or pottery as a

preliminary to a wax polish or a gasoline wash. White cement tiles or

pottery are very porous and a thin coating of clear white shellac will

prevent over absorption of surface coloring if the shellac is permitted

to dry thoroughly. Shellac should be applied after the surface is

thoroughly dried to prevent a sticky surface.

 

THE GASOLINE WASH is made by mixing white oil paint (flake white or zinc

white) with black paint (ivory black or lamp black) until a gray tone is

secured. This mixture should be made in a cup or bowl so that gasoline

can then be added until the paint is almost as thin as water. To this

mixture green or blue paint or other color should be added until the

right hue is secured. This is then brushed onto the tile surface and

brushed well into the crevices and countersunk sections as it is

important that the low sections be well filled. After the wash has dried

thoroughly, a soft cloth is used to rub off all the surplus. This will

leave the gasoline wash remaining only in the bottom or lower portions

giving a pleasing finish. After this has dried a wax rub may be placed

over it.

 

A WAX RUB is produced by taking either wax tan shoe polish or floor wax

and rubbing it onto the cement with a soft cloth. The cement should be

thoroughly dry before the wax is placed upon the surface. After a few

minutes a soft brush or woolen cloth should be used to polish the waxed

surface.

 

A wax rub can be applied over a gasoline wash, but only after the wash

has been given time to thoroughly dry. If the gasoline wash is not dry,

the wax will remove it in parts and destroy the effect produced by the

gasoline wash.

 

A COLOR CEMENT SURFACE FINISH is made by mixing a thin mixture of color

and cement which is then brushed onto the tile. The tile or surface to

be finished with cement should not be dry or be permitted to dry after

it has been removed from the mold. Previous to the application of the

cement color, the tile should be well moistened. After the color has

dried for several hours upon the surface, a cloth balled or gathered so

as to form a padded surface should be used to remove the color from the

high parts.

 

A SLIP SURFACE FINISH is where the tile or surface has been completed in

single or several colors and when hardened sufficiently in water, a thin

slip of color cement is placed over the entire surface and permitted to

settle into the hollows, leaving the higher portions to appear more

clearly through the colored slip. If the surface is a tile, it should

then be permitted to harden in shallow water placed in a tray with the

tile placed carefully into it so that the water does not reach the color

slip portions. If the object is a vase, it may be filled with water to

harden the outer surface properly. If the color has been used as a layer

on the inside, the bowl or vase should be placed in a pail and water

poured into the pail so that the object is surrounded with water. A

weight or board can be placed so as to prevent the object from floating

if it commences to do so.

 

COLOR MAY BE SPRAYED by mixing a thin mixture of color and cement and

spraying it onto the tile or pottery surface with a fixitive blower such

as may be obtained at artists’ supply stores and which is used by

artists for spraying a solution of shellac (termed fixitive) onto

charcoal or pencil drawings.

 

The color should be repeatedly stirred to keep it well mixed and if the

sprayer becomes clogged, it should be rinsed in water.

 

Too much color should not be sprayed at a time as it will fail to be

absorbed and run on the surface, resulting in streaks.

 

SPATTERED COLOR FOR SURFACES is secured by dipping a short-haired

bristle brush (the bristles are best when they are about one inch long)

into color cement and causing the color to spatter onto the surface by

rubbing a knife edge or straight edge of a stick along the brush. This

will cause the bristles to release suddenly, throwing pigment in the

opposite direction onto the object. A trial should first be made on

paper surface before the actual surface is used to avoid too much color,

such as would come from an overcharged brush or too vigorous rubbing.

The surface of the object should be moist or dampened well previous to

the spattering.

 

SPRINKLED DRY COLOR can be applied to surfaces. This will give a

pleasing effect in certain places where an antique or scattering of dry

color will enter into the nature of the design. The dry pigment can be

sprinkled onto the surface only where the surface has been covered with

a layer of other color that is still moist. This is necessary in order

that the dry color will absorb sufficient moisture from the other color

to amalgamate with the first color.

 

TEXTURE SURFACES are produced by working on the surfaces while they are

still moist or soft enough to admit the use of a tool or edge to press

or model the surface. Even when a surface might have become quite hard

it may be tooled or chipped and a cement wash or gasoline wash used to

give the tooled parts a unifying color.

 

REPEATED SURFACE COLORING may be done where the first coloring is not

satisfactory. It will be found that a more pleasing effect is often

produced by the second surface coloring being placed over the first.

Care should be taken that so much rubbing does not occur that it wears

parts of the tile or pottery surface that are soft.

 

SURFACE FINISHES PERMIT OF EXPERIMENTING and the craftsworker in color

cement must test out different combinations in order to achieve the most

desirable quality to respond to personal choice. A brilliant color wash

will often bring out the pattern in pleasing contrast, and at other

times it may be over absorbed and produce a mottled undesirable quality.

The condition of the molds and the amount of sand in the mixture all

influence the surface of the object and in turn influence the result of

the surface finishes.

 

[Illustration: A Surface Finish for Cement Handicraft]

 

 

 

 

[Illustration]

 

CHAPTER 17

 

Decorations in the

Open

 

[Illustration]

 

 

COLOR AS OUTER ARCHITECTURAL DECORATION was much used on the buildings

of Egypt and Assyria. The winged sphere in gold and amber against a

background of dark blue was commonly used on the outer walls of Egyptian

buildings and the processions of warriors and ancient kings decorated

the walls of the Assyrian cities.

 

THE GRECIANS USED COLOR ALSO and the beautiful Parthenon was decorated

with color and the restored model in the Metropolitan Museum of Art in

New York shows their use of color architecturally. The great Acropolis

was resplendent in bas-reliefs on the outer walls in color, gold and

silver.

 

THE ROMANS USED COLOR OUT OF DOORS on their buildings and the Etruscans

built in terra cotta coloring the outer walls with gorgeous decorations.

They recognized that architecture could be dignified and noble with

proper use of color decorations to enrich the building as a whole.

 

MURAL DECORATIONS IN THE OPEN were used by the Egyptians, examples of

which remain in our museums today, and so permanent were their colors

that the color schemes are apparent even at this day thousands of years

after their artists applied them.

 

Pompeians with their house-tops massed against their blue skies were

prompted to use orange-red largely in their decorations which were

lavishly applied in their gardens and other surroundings.

 

THE CHINESE USED COLORS SIMILAR TO THE POMPEIANS and their decorations

give brilliant notes to their buildings creating pleasing effects. The

Chinese medium has been one largely of lacquer which has been used over

their gold and painted color, producing transparent qualities making it

difficult to know where the actual surface begins.

 

COLOR ON OUTSIDE BUILDING SURFACES exists on many of the Italian

cathedrals and enriched color facades were used on many houses during

the Gothic period of which there remains examples at Heldesheim and

Nurenberg and other cities.

 

COLOR IN AMERICAN ARCHITECTURE IS POSSIBLE with the use of color cement

and with careful analysis of the colors used and methods of hardening,

the patient worker can accomplish much toward realizing this much sought

possibility.

 

THE FIRST STEP TOWARD SUCCESSFUL USE OF COLOR CEMENT in the open is to

realize that color used at all times must be protected from drying too

rapidly. If it does so, it will disintegrate and chalk away gradually.

The drying of color cement should be retarded as much as possible and

kept moist as long as the hardening process has not completed. It is

impossible, of course, to apply water to the face of a working surface

without destroying the glaze of the color, or the surface setting layer

once the surface commences to dry. Water applied at this time will cause

the surface to float in sections and ruin the entire surface. Therefore

the best way is to arrange for the water to be absorbed from the back

and this can be done easily where the panel or mural decoration is a

separate section to be applied to the building surface afterwards.

 

WHERE THE MURAL IS TO BE APPLIED TO THE WALL the surface must be first

roughened, next thoroughly dampened with water, then a layer of wet neat

cement placed upon it. The bed of cement or sand and cement is next

applied and the subject then applied onto this surface all at one

sitting. This is necessary to avoid any part drying, as it will be

impossible to dampen the surface for postponed work.

 

BETTER RESULT ON WALL DECORATION is possible where the color cement can

be applied before the wall mass has dried out. If the forms or board

walls can be removed before the cement has thoroughly set, whatever

color cement or cement underlayers necessary to the color surfacing are

placed upon it, will stand greater chances of remaining as a permanent

part of the whole structure.

 

TO PROCEED WITH A MURAL PANEL a pan of metal two inches larger each way

than the panel dimensions should be made from galvanized sheet metal.

This is to hold the mural cement slab onto which the subject is to be painted.