CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF PINS
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
CLINTON ROBERTSON, of 166, Fleet Street, in the City of London, Civil
Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Eighteenth day of April, in the ninth year of Her reign,
did, for Herself, Hér heirs and .successors, give and grant unto me, the said
Joseph Clinton Robertson, my exors, admors, and assigns, Her especial licence,
full power, sole privilege and authority, that I, the said Joseph Clinton
Robertson, my exors, adiñors, and assigns, or such others as I, the said Josephi
Clinton Robertson, my exors, admors, or assigns, should at any time agree
with, and no others, from time to time and at all times during the term
of years therein.expressed, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, and
also in the Islands of Guernsey, Jersey, Alderney, Sark, and Man, and, in all
Her said Majesty's: Colonies and Plantations abroad, the Invention of "CERTAIN
IMPROVEMENTS IN THE MANUFACTURE OF PINS;" communicated to me by a
certain foreigner residing abroad, in which said Letters Patent is contained a
proviso, that I, the. said Joseph Clinton Robertson, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in Her said Majesty's High Court of

page_text: Chancery within six calendar months next and immediately after the date of
the said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will moro fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Joseph Clinton Robertson, hereby declare that the nature of the said Invention,
and in what manner the same is to be performed, are fully described in and
by the present Specification thereof, reference being had to the Drawings
hereunto annexed, that is to say:-
Pins are at present made for the most part of brass wire coated with tin to
protect them from oxidation; for though pins have been also made and may
be still made for particular purposes of irou and steel wire similarly coated,
yet, owing to the difficulty of coating the latter with tin (arising from the
small affinity which tin has for iron and steel), it has been hitherto found im-
practicable to produce iron or steel pins of sufficient sharpness and smoothness
to be suitable for general use, or applicable to any other than coarse fabrics.
Now, the nature of the said Invention consists in manufacturing pins of
iron and steel wire equal to the best brass pins in point of sinoothness, and
far superior to them in respect of strength, sharpness, and tenacity, and the
means by which this is effected may be described generally as consisting in
giving the iron and steel pins a coating of copper previous to coating them with
tin, the copper adhering readily to the iron or steel, for which it has naturally
a strong affinity, and the tin combining with equal readiness with the super-
imposed copper, or in coating them with copper alone without any additional
coating of tin. The details of these improved methods of manufacturing pins
of iron and steel wire (so far as they differ from those of the methods hitherto
followed) I shall now proceed to describe under the different heads into
which the same practically divide themselves.
The Selection and Preparation of the Wire-The iron or steel wire employed
should be very round, and to protect it from rust it should at the last drawing
be lubricated by means of a spongo saturated with oil, placed between the
draw plate and reel. In all the subsequent stages of the manufacture caro
should also be taken to preserve tho pins from oxidation by keeping them well
oiled or greased.
The Cleansing and Polishing.-The wire being cut into pins and these
headed and pointed, all according to the usual methods, tho pins are thrown
into a revolving cylinder of wood containing a bath of soap and water in a hot
state. A side elevation of this cylinder is given in Figure 1 of the annexed
Drawings, and an end elevation in Figure 1. It is of the capacity of about
nine and a half gallons, but should not contain more than about one gallon and

page_text: a half of water, with about two ounces of soap dissolved therein, as this quantity
will be sufficient for the treatment of about thirteen pounds weight of pius at
a time. The cylinders when thus charged is made to revolve for about a
quarter of an hour, at the expiration of which time the pins are found free
from the oil wherewith they were previously coated, and also very much
smoothed and polished by their rubbing one against the other. B, B, are the
uprights which support the cylinder; E, F, the bearings in which it turns; C
is the stopper of an aperture through which the soap and water and pins are
introduced; D the handle by which the cylinder is made to revolve.
The Drying. The pins are next dried by transferring them, to another
cylinder, such as is represented in Figure 2, side elevation, and end elevation,
Figure 2*, partially filled with well dried sawdust (preferring for the purpose
the sawdust of poplar wood), and causing this cylinder to revolve by means of
the handle E for about ten minutes. B, B, are the ends of the axis on which
this second cylinder revolves, and G, G, the standards in which the axis has
its bearings; F is the door. Instead of employing a cylinder of this description
the pins might be thrown into a bag or bags partially filled with the sawdust,
and the requisite friction produced by swinging or rolling these bags about for
the same length of time.
The Copper-coating Bath or Mixture.-Into a glass or stone vase the Inventor
puts about one and a half gallons of soft water, seven-tenths of a pound of sul-
phuric acid, of lb. of salt of tin, 18 lb. of crystallized sulphate of zinc, and
108 grains of pure sulphate of copper, and leaves this mixture to work for about
twenty-four hours, so that the salts and sulphates may be properly dissolved.
I find this to be on the whole the mixture best adapted for the purpose in
view, but most of the ingredients mentioned may have others substituted for
them, as for example, any other acid or substance producing like effects may
be used instead of the sulphuric acid, or the sulphate of tin may be substituted
for the salt of tin, or any of the salts of copper or zinc used in place of the
sulphates of copper or zinc.
The Copper-coating Process.-The mixture prepared as last herein directed is
introduced into a revolving cylinder of the same form and capacity as that
represented in Figure 1, and before described, and the pins (about 13+ lbs.
weight, as aforesaid,) are thrown into the midst of it.
The cylinder is then caused to revolve for about half an hour, which serves
at once to remove any verdigris from the pins, to impart a high polish to
them, and to give a beginning to the copper-coating process. At the end of
the half hour or thereabouts 231 grains (more or less) of chrystallized sul-
phate of copper of about the roughness of marine salt, and 150 grains of

page_text: chrystallized sulphate of zinc (previously dissolved in soft water), are added to
the mixture in the cylinder, and the whole again agitated for about a quarter
of an hour. The pins are by this operation' not only completely conted but
acquire a very considerable degree of polisli: The copper liquor is then drawn
off and the pins twice suffused with cold water, while the cylinder is kept
rotating at the rate of about one turn a minute. The pins are then taken out
and thrown into a wooden tub (A), of the form represented in Figures 3 and 4,
containing hot soap and water, after which the tub is hermetically closed by
putting on the rimmed cover B and making it fast by the looks and oyes
C, C, D, D. The pins are now well shaken by overturning the tub and raising
it up again some thirty or forty times, more or less. The contents of the tub
are then emptied into a wooden strainer, shewn in Figure 5, liaving a per-
forated bottom of tinned plate iron (Figure 6), and when tlie soap and water
has drained from the pins the latter aro placed whilo yet wet in a "rovolving
cylinder, similar to that represented in Figure 2, and before described, and
containing well dried sawdust (using by preference, as before, the sawdust of
poplar wood,) or well dried bran free from flour:
.
..:...
The pins are now dried by turning the cylinder for from five to six minutes,
at the expiration of which time they exhibit a very beautiful copper appearance,
and may be used in that state without tinning if thought desirable. A con-'
siderable portion of the coppering ingredients may be saved after each
operation by allowing the mixture to settle, then drawing off the supernatant
liquor and adding thereto 386 grains of sulphuric acid, to bring it up to a
strength sufficient for subsequent use.
"
Tinning and Blanching.-The pins are tinned and blanched in the
ordinary manner and by the ordinary processes used for those of brass wire,
that is, by laying them on plates of very thin tin placed one above another'in
a tinned copper boiler containing a solution of about 4 pounds of crude
tartar or cream of tartar (preferring the latter) in about twenty-two gallons
of water, and then setting the whole to boil for about twelve hours." The
tartar solution should be prepared at least twenty-four hours previously, and
left to work for that time in order that the ingredients may be thoroughly
dissolved and intermixod; about 43 lbs. of cream of tartar is the minimum
quantity which should be used, and the brilliancy and celerity of the tinning
will increase in proportion to the increase of the quantity employed. The
pins are then taken out of the boiler and dried in a revolving cylinder or
leathern bag, as before explained, after which they are ready for use...
And having now described the nature of the said Invention, and in what
manner the same is to be performed. I declare that what is claimed is,
1.

page_text: First, the manufacture of tinned iron and steel pins by means of the series
of processes herein-before described.
Second, the coating with copper of pins made of iron or steel before tinning
and blanching the same, as before described, by whatever mode or modes the
same may be manufactured in other respects.
And, third, the manufacture of pins of iron and steel coated with copper only
(but not tinned), as before described.
In witness whereof, I, the said Joseph Clinton Robertson, have hereunto
set my hand and seal, this Seventeenth day of October, in the year of
our Lord One thousand eight hundred and forty-six.
J. CLINTON (L.B.) ROBERTSON.
AND BE IT REMEMBERED, that on the Seventeenth day of October, in
the year of our Lord 1846, the aforesaid Joseph Clinton Robertson came
before our said Lady the Queen in Her Chancery, and acknowledged the
5 Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.