IMPROVE- MENTS IN THE MANUFACTURE OF LETTERS, NUMERALS, AND ORNAMENTS FOR WINDOW SIGNS, SIGN BOARDS, NAME PLATES, STREET PLATES, AND FOR OTHER LIKe Uses
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by John Brock at the Office of the
Commissioners of Patents, with his Petition, on the 10th January
1871.
I, JOHN BROCK, of Birmingham, in the County of Warwick, Manu-
facturer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE MANUFACTURE OF LETTERS, NUMERALS, AND ORNAMENTS FOR WINDOW
SIGNS, SIGN BOARDS, NAME PLATES, STREET PLATES, AND FOR OTHER LIKe Uses,”
to be as follows:
-
The said letters, numerals, and ornaments are ordinarily made of glass,
china, or earthenware, and are attached to the window or sign board or
other surface by cement. My Invention consists in making the said
letters, numerals, and ornaments in the manner herein-after described,
whereby they are made more economically than by the ordinary process,
I will describe my
and are very much stronger and more durable.
Invention as applied to the manufacture of letters.
I make the base or foundation of the letters of cast iron, the casting
being made by preference hollow at back in order to give lightness to
the said base or foundation. Or the letters may be made of wrought
iron by stamping in dies from sheets or plates of wrought iron. Or the
letters may be made of steel either by casting or stamping. I clean
the surface of the base or foundation letters by dilute sulphuric acid,
carefully washing them with water after the treatment with the said

page_text: acid. I dry them at a temperature of about 150 degrees Fahrenheit.
When dry I plunge the said' letters into a mixture of finely ground
semi-transparent enamel and water,, the mixture having about the
consistence of cream. A small quantity of gum or other adhesive
matter is used in this mixture. The letters thus coated are dried at a
temperature of about 150 degrees Fahrenheit, and when dry the whole
of the coating is wiped from the backs of the letters. They are then
heated in a muffle to a sufficient temperature to fuse the coating of
semi-transparent enamel upon them. They are coated a second time
with a white or coloured enamel, the said white or colored enamel
being applied and fused in the manner already described.
In order to ornament the surface of the letters another coating of
enamel mixed with gum water is applied and dried. To the dried
surface a stencil plate in which the desired ornament is cut is applied
and held firmly thereon. By means of a stiff brush rubbed over the
stencil plate the last-described coating is removed from all those parts
of the letter corresponding to the cut away portions of the stencil plate,
and on removing the stencil plate the required design in unburned
enamel is left on the latter. By again heating in a muffle the design
is fused on to the letter.
When an ornament in gold is to be produced a coating of whiting
and gum water is employed, and by means of a stencil plate and brush
portions of the whiting are removed, the said portions corresponding to
the ornament to be produced. By means of a brush an amalgam of
brown grain gold mixed with turpentine is applied to the exposed.
portions of the surface, the whiting limiting the application of the gold
mixture to the required portions of the letter. The letter is again heated
in a muffle, and on its removal therefrom the gold portion is burnished
in the ordinary manner.
My Invention is applicable not only to letters and numerals, but to
detached ornaments to be applied to surfaces in the same way as letters
and numerals. When the shape of the article renders the application of
the enamel by immersion inconvenient, the said enamel may be applied
by means of a brush, or it may be used in the state of dry powder and
dusted on the surface of the article.