AN IMPROVEMENT IN SCRATCH BRUSHES to be as follows:-
Year: 1885

page_text: I CHARLES EDWARD DAY, Junior, of 8 Nelson Terrace, City Road, Scratch
Wire Manufacturer do hereby declare the nature of the said invention for
"AN IMPROVEMENT IN SCRATCH BRUSHES to be as follows:-
"
My Invention relates to scratch brushes such as are used by gilders and others,
and which consist of wires or wire bristles fixed in a wooden or other stock. With
these brushes, as ordinarily made, it has been found that, owing to a want of
stiffness of the wires, the scratching operation is ineffectually performed as the
wires or wire bristles bend back or curl over so that the ends of the wires are not
properly presented to the article under treatment.
My Invention is designed to obviate this objection, and it consists in crimping
the wires so as to impart the necessary degree of stiffness to the brush, and this
I effect by drawing the wire between a pair of grooved or fluted rollers. These
rollers are mounted in a suitable support and provided with means for regulating
the pressure and for separating them to allow of the introduction of the wire
between them.

page_text: I, CHARLES EDWARD DAY, Jun* of 8 Nelson Terrace, City Road, Scratch Wire
Manufacturer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
My Invention relates to scratch brushes, such as are used by gilders, platers, and
others, and which are made of fine wires of brass, german silver, and similar alloys,
drawn or otherwise fixed in the manner of bristles, into a wooden, or other stock,
My Invention is designed to obviate the objections inherent to scratch brushes as
ordinarily made of plain straight wires, and it consists in making such brushes of
wires which have been crimped by being passed between a pair of grooved or
fluted dies, or rollers, in the inanner hereinafter described. In the accompanying
drawing forming part of this specification, I have represented, on a considerably
magnified scale, a wire being crimped for the purposes of my invention. The
mode of drawing the "knots' or bunches of the crimped wires into the stock, or
otherwise fixing them therein, needs no description, as it in no way differs from
the modes usually practised by scratch brush makers. The effect of crimping the
wires, is to cause them to occupy more space in the brush, and therefore to form
an apparently fuller brush, with fewer, and finer wires, than if they were straight,
the crimped wires being mutually supporting, so that an amount of elasticity is
imparted to the brush which is not obtained with straight wires, the effect of the
greater fulness of the brush, and the mutual support of the wires, being that the
scratching operation is more effectually performed, as the ends of the wires are
properly presented to the work, and the wires being supported by their neighbours,
do not curl up like the ordinary scratch wires used. By the method of crimping,
of my invention, I am enabled to use finer wires for the purposes of a scratch brush
than have ever before been used, and I am moreover enabled to eradicate the
tendency to curl up, which brass and other wire has, when it comes from the
drawing dies. For example, I am enabled to use for the manufacture of scratch
brushes, brass wire weighing 1 oz per 2,000 yards and when crimped as hereafter
described, to manufacture therewith a brush apparently fuller than with 25% more
of straight wire.
The mode of crimping the wire is peculiar.
It consists in drawing the wire between a pair of fluted, or corrugated dies,
preferably stationary rollers, the teeth, or corrugations of which, mesh together only
just sufficiently to indent or bend the wire slightly out of the straight line, without
nipping it between two opposite surfaces, that is to say, the wire is unsupported
at the points where the tops of the teeth, or corrugations, press against it so that
the wire is not flattened, but retains its original round section, and equal rigidity
in all directions.
The degree of pressure is varied according to the fineness of the wire. The
principle of the process, is based on the fact, that, if a wire be drawn over an edge
with sufficient pressure to bend it beyond its limit of elasticity, the wire will be

page_text: permanently curved, as may be readily seen by drawing it over the finger nail.
Now, by providing a series of two, or three alternating and opposite edges, such
as I have represented on a greatly magnified scale (about 5 times full size), the
wire in being drawn between them, is caused to assume a spiral, or helical curvature,
of a pitch corresponding to the teeth of the die. As the wire being held, is
prevented from twisting continuously in one direction, the direction of this helical
form of crimp becomes alternately reversed at intervals, depending on the length
of wire which is free to twist.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The spiral crimping of wire for the manufacture of scratch brushes, sub-
stantially in the manner herein described.
2. The manufacture of scratch brushes of wire which has been spirally crimped,
in the manner herein specified.