IMPROVEMENTS IN APPARATUS TO BE USED IN THE PREPARATION OF METAL SURFACES FOR ETCHING, ENGRAVING, AND SIMILAR PURPOSES
Year: 1883

page_text: LETTERS PATENT to Joseph Julius Sachs of Gray's Inn Road in the County
of Middlesex for an Invention of "IMPROVEMENTS IN APPARATUS TO BE USED
IN THE PREPARATION OF METAL SURFACES FOR ETCHING, ENGRAVING, AND
SIMILAR PURPOSES
"
PROVISIONAL SPECIFICATION left by the said Joseph Julius Sachs at the
Office of the Commissioners of Patents on the 5th June 1883.
JOSEPH JULIUS SACHS of Grays Inn Road in the County of Middlesex
"IMPROVEMENTS IN APPARATUS TO BE USED IN THE PREPARATION OF
SURFACES FOR ETCHING, ENGRAVING, AND SIMILAR PURPOSES.
"
METAL
This invention relates to the preparation, by the sand blast, of metal surfaces for
etching or engraving according to various processes patented by the present
applicant under Letters Patent numbered respectively N° 609, 1419, 1909, 2966,
all of the year 1880, N° 266 of 1881, and N° 1166 of 1882.
In carrying out the said processes the metal surface to be etched or otherwise
treated is first coated with a material which is termed a "resist." The design to
be etched on the surface is then drawn upon the "resist," and such parts as are to
be removed are picked out, leaving the metal surface exposed. When the design
is fairly plain, this can be readily effected, but when the design is of a complicated
nature, such for instance as a piece of lace, the time taken up in removing the
resist would be very great and the cost of the etching or engraving would thus
become a matter of considerable moment.
From experiments inade I have found that the "resist" can with facility be
removed by the sand blast from the most complicated designs, and the object of
the present invention is to produce an apparatus to be used in the application of
the sand blast to this purpose
The apparatus consists, by preference, of an oblong chamber of considerable
height in which the metal surface to be acted on is placed. This chamber also
serves as a settling chamber for the sand, and is provided at its upper end with a

page_text: flue by which the current of air employed to project the sand, and with it the finer
particles or dust of the sand, can escape.
The bottom of the chamber is hopper shaped, so that the sand shall always
return after use to a trunk with which the hopper is provided. The trunk extends
downwards into an air chamber, preferably of cylindrical form, to the lower part
The bottom of the
of which air is supplied under pressure from a suitable blower.
trunk is closed by a metal casting in one with which is the jet which projects
upwards through the trunk into the oblong chamber. On either side of the jet a
row of holes is made through the casting to allow for the passage of the sand.
These holes are capable of being closed by a suitably arranged slide. The sand, as
it passes out of these holes in small streams, is met by the current of air which
drives it up the jet onto the surface to be acted on.
In order that the air under pressure shall act in the most perfect manner on the
streams of sand, we place horizontally across the air cylinder and a short distance
below the mouth of the jet, a baffle plate, which will deflect the air and divide it
into two currents, giving to each a sideway direction in respect of the streams of
sand issuing from the sand openings. In addition to the baffle plate, we may
suspend just below the mouth of the jet, a guide plate which will serve not only
to concentrate the currents of air, but will arrest the fall of the sand, thereby
ensuring a proper supply of sand to the jet.
The article to be treated is placed on a suitable carriage which runs on rails
arranged longitudinally of the oblong chamber. The rails extend beyond the
casing or chamber, and are supported at their outer end by a suitable standard.
When a flat surface is to be operated on, the carriage will be provided with means
for traversing the article from side to side over the jet of sand, so that the whole
surface may be acted on.
When a cylindrical surface is to be treated which will most usually be the case
(a cylinder being more convenient for printing from) the cylinder is centered on a
spindle which rests at either end on a pair of friction rollers carried by the
carriage, and is provided with a hand wheel by which it may be slowly rotated as
the operation of sand blasting proceeds.
A suitable opening is made in one end of the oblong chamber for the withdrawal
and entrance of the carriage, and a sliding shutter is provided to close the opening
during the working of the apparatus.
It may be here remarked that the "resist" above referred to may consist of
varnish, asphaltum or any other suitable material or substance, for instance a thin
film of metal which is not likely to be affected by the etching solution employed
in metallic or galvanic bath used, as mentioned in my previous Patent N° 1166 62.
The design or pattern or picture to be transferred to the surface to be treated,
may consist of any spun or woven, open or closed fabric or material or substance,
or thin films of metal, cotton, silk, woollen or other threads which can be wound
round the roller or surface by machinery or otherwise, and the open part treated
by the sand blast whilst the part protected by the threads or other part of the
pattern is not affected by the blast.
The design, drawing or pattern to be transferred to the surface to be treated,
may be also produced by the action of light or in any other suitable way. For
instance it may be cut out by hand or may be etched through thin sheets of metal
or produced in any other suitable way, but the fabric or material used must be of
such a nature as will resist the action of the sand blast.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Julius Sachs in the Great Seal Patent Office on the
5th December 1883.
JOSEPH JULIUS SACHS of Grays Inn Road in the County of Middlesex
"IMPROVEMENTS IN APPARATUS TO BE USED IN THE PREPARATION OF METAL
SURFACES FOR ETCHING ENGRAVING AND SIMILAR PURPOSES
"
This Invention relates to the preparation by the action of the sand blast or the
impact of hard particles of metal surfaces for etching or engraving according to
various processes such as are described in the Specifications of prior Letters Patent
granted to me more especially in those numbered 266 of One thousand eight
hundred and eighty one and 1166 of one thousand eight hundred and eighty two.
In carrying out the said processes the inetal surface to be étched or otherwise
treated is first coated with a material which is termed a "resist." The design to
be etched on the surface is then drawn or placed upon the "resist" such parts as
are to be removed are picked out leaving the netal surface exposed and ready for
the action of the acid. When the design is fairly plain this can be readily effected
by hand but when the design is of a complicated nature such for instance as a
piece of lace the time taken up in removing the resist at the parts where the
surface is to be eaten away would be very great and the cost of the etching or
engraving would thus become a matter of considerable moment.
From experiments made I have found that the resist can with facility be
removed from the most complicated designs by means of the sand blast or the
impact of hard particles and the object of the present Invention is to produce an
apparatus adapted to be used more especially for this purpose but it may of course
be employed for any analogous purpose such for example as to put a grain onto
the entire roller or other surface.
I will describe my said Invention with reference to the accompanying drawings
wherein Figure 1 Sheet I is a side elevation Fig: 2 a front view and Fig: 3 n
plan of an apparatus constructed according to my Invention for effecting the above
object Figures 4 and 5 Sheet II are respectively a transverse and a longitudinal
vertical section of the apparatus drawn to a larger scale. The apparatus consists
of a chamber A preferably of an oblong form set on end and of considerable height
and of uny
suitable depth and width in which chamber the metal surface to be
acted on is placed, the said chamber also serving as a settling chamber for the sand
or hard particles employed and being provided at its upper end with a flue by
which the current of air (employed to project the sand or hard particles) can
escape carrying with it the finer particles or dust resulting from the operation."
The bottom of the chamber A is doubly inclined or hopper shaped as shewn at a.
Fig: 4 so that the sand shall always return after use to a trunk a² at the bottom
of the said chamber. This trunk a³ which is of the same depth as the chamber,
extends downwards into an air chamber B preferably of cylindrical. form to the
lower part of which air is supplied under pressure from any suitable blowing or
air forcing apparatus.. The bottom of the trunk inside the chamber B is closed
by a closing piece or casting C in one with which is formed a long jet slot
or nozzle c. which projects upwards through the trunk a into the chamber A.-
This jet slot or nozzle c. is placed longitudinally of the chamber A and its width is
equal or nearly so to the depth of the chamber In the piece C and on either side
of the jet slot or nozzle c are formed holes or passages o³ to allow for the passage

page_text: downwards of the sand or hard particles. These holes are capable of being closed
or opened by a suitably arranged slide or slides D correspondingly perforated and
provided with a handle or handles which project through the front of the air
chamber B.-This is for the purpose of regulating the supply of sand to the jet.
The sand or its equivalent as it passes out of these holes in small streams is met
by the current of air entering as indicated by the arrows in Fig: 4 which current
of air drives the sand or its equivalent up the long jet c. on to the surface to be
acted upon as seen in the figure. In order that the air under pressure shall act in
the most perfect manner on the streams of sand. I suspend or fix horizontally
across the upper part of the air cylinder B and some distance below the mouth of
the long jet c a baffle plate E with passages at the sides which plate will deflect
the air and divide it into two currents giving to each a side way direction in
respect of the streams of sand issuing from the openings at c². In addition to the
said plate E a guide plate E' may be suspended just below the mouth of the long
jet which will serve not only to concentrate the currents of air but will arrest the
fall of the sand thereby ensuring a proper supply of sand to the jet.
The article to be treated is placed on a suitable carriage such as F which runs
on rails f. arranged in proximity to the chamber A as shewn clearly in Figures 1
and 2. The rails f. are supported by suitable standards f¹.
When a flat surface is to be operated upon the carriage F should be provided
with means for giving to the article a transverse motion over the sand blast so
that the whole surface may in turn be presented to the sand issuing from the
long jet c.
When a cylindrical surface is to be treated, that being the most usual form for
printing surfaces, the cylinder is centred as shewn in the drawing on a spindle g.
carried by the carriage F it being held to the spindle by gripping cones g². The
spindle g. is provided at one end with a hand wheel g³ by which it may be slowly
rotated to present a fresh surface to the action of the sand blast as the operation
proceeds and at the other end is threaded to receive a nut by which the outer
cone may be forced into the end of the cylinder to be operated upon.
An opening at A³ of any suitable shape capable of being tightly closed is
provided in front of the chamber A for the introduction and withdrawal of the
cylinder or other article to be operated on. This opening is closed by a plate or
shutter A which may be a sliding shutter or it may be a plate or disc carried by
the carriage F or spindle g. so that it is run into place when the article is intro-
duced into the chamber thereby closing the opening during the working of the
apparatus. The plate or disc may be secured in place by buttons as at a³ or in any
suitable way.
It may be here remarked that the "resist" above referred to may consist of
varnish asphaltum or any other suitable material or substance for instance a thin
film of metal which is not likely to be affected by the etching solution employed in
a metallic or galvanic bath used as mentioned in my previous Patent N° 1166 83.
The design or pattern or picture to be transferred to the surface to be treated may
consist of any spun or woven reticulated fabric or other reticulated material or
substance or thin strips of metal or cotton silk woollen or other threads which can
be wound round or placed or fixed upon the roller or other surface by machinery
or otherwise and the surface thus covered may be subjected to the sand blast or
the impact of hard particles in the apparatus herein before described whilst the part
protected by the overlaid pattern is not affected by the said blast or impact-The
design drawing or pattern to be transferred to the surface to be treated may be also
produced by the action of light or in any other suitable way.
But the fabric or material used must be of such a nature as will resist the action
of the said blast or the impact of the hard particles.
Having now described and particularly ascertained the nature of my said
Invention and the manner in which the same is or may be used or carried into effect
I would observe in conclusion that what I consider to be novel and original and

page_text: therefore claim as the Invention secured to me by the hereinbefore in part recited
Letters Patent. is.
First The apparatus above described with reference to the accompanying
drawings for applying the sand blast in the preparation of metal printing and
embossing surfaces.
Second: In apparatus for the purpose described the employment in combination
with means for projecting sand or hard particles of what has hereinbefore been
termed a long jet slot or nozzle c. for projecting the sand or hard particles
employed in a thin stream or sheet against the surface to be operated upon.
Third: In apparatus for the purpose described the combination of the chamber A
with an inclined lower part the long jet slot or nozzle c. and the holes or passages c³.
whereby the sand or hard particles employed are allowed to descend to meet a blast
for the purpose set forth.
Fourth In apparatus for the purpose described the combination of the chamber A
with an inclined lower part the long jet slot or nozzle c. the holes or passages c³. and
the deflecting plate E or plates E and E' substantially as described with reference
to the accompanying drawings.
In witness whereof I the said Joseph Julius Sachs have hereunto set my hand
and seal the 29th day of November in the year of our Lord one thousand eight
hundred and eighty three.
JUSERN, JULIUS SACHS. (L.S.)