IMPROVEMENTS IN THE MANUFACTURE OF OAKUM AND YARN
Year: 1879

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF OAKUM AND YARN." A communi-
cation from abroad by Thomas Harrison Dunham, of the United States of
America
Sealed the 23rd December 1879, and dated the 29th October 1879.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 29th October 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents;
Southampton Buildings, London. "IMPROVEMENTS IN THE MANUFACTURE OF OAKUM
AND YARN." A communication from abroad by Thomas Harrison Dunham, of the
United States, of America.
This Invention relates to the manufacture of oakum and yarn from cotton.
Oakum made from tarred flax or hemp was the only caulking material in general
use until untarred cotton was introduced a few years ago, and the latter has since
been used to a considerable extent as a caulking material for light vessels and decks;
but this material is not adapted for general use as a substitute for oakum, and has
not been so used but only in seams not exposed to any great strain. This untarred
cotton is objectionable by reason of its tendency to absorb moisture, which soon rots
the fibre and renders it useless, and also by reason of its liability when dry to work
out of the seams, and in both these respects it is much inferior to the oakum usually
employed.
The article made according to this Invention and designed to take the place of
common oakum is tarred cotton oakum ready for use without the preliminary hand-
spinning requisite with the common oakum, and I employ a special mode of treating
the cotton, as hereinafter described, that is to say:-The cotton is first taken from
the bale to the opener or lapper, and then to the carding machine, from which the
cotton usually runs into a trough or upon an endless apron, by which it is carried to
a drawing head, when it is put into cans and taken to the drawing frame; it is
then doubled and drawn to make the fibre straight and form it into a sliver or
roving, so called. This roving is uniform or very nearly so throughout its length}
J Prins A.1

page_text: and usually about an inch in diameter, although its diameter may be varied
according to the size of the spun oakum required, as will be clear to all caulkers
without farther description. This sliver is laid upon an endless apron of strong
cloth, which passes into and out of a tank and between a pair of squeezing rollers.
The tank being filled with boiling tar or tar dissolved in naphtha, or otherwise
made sufficiently fluid, the motion of the apron will carry the roving through the
tar and between the rolls, which express the superfluous tar, the roving after leaving.
the feed roll being ready for use as oakum, the strand of fibre having been reduced
to the desired size before it is tarred, and constituting a new article, namely, tarred
cotton oakum.
Two or more strands may be passed through the tank and rollers on a wide
apron as well as one strand, it being found that the strands always keep separate
and distinct.
.
This new article differs from all oakum heretofore known in that the fibre of
cotton is much more uniform both as to length and firmness of the fibres than the
fibres of hemp or flax, and also much finer than any fibre heretofore found in oakum;
its strength is also very much greater, and it will when tarred make a very fine
compact wedge, which clings with great force to the seam, will not rot nor become
displaced, and which completely fills the space between the planks, especially the
apex of the wedge, all oakum when in place being wedge shaped, but the ordinary
oakum by reason of the coarseness of its fibres having a blunt and uneven apex
instead of the fine sharp apex produced with this tarred cotton oakum.
When the tar is kept at boiling point it is very desirable to keep the roving
always upon the feed apron, and to ensure this an upper apron of wire is used, both
aprons being properly guided, so that the roving is held between them, and thus
prevented from accidental displacement. When the first roving is nearly exhausted
a second is pinned to its end in a manner well known, and thus the operation is
made continuous.
The gist of this part of the said Invention consists in the new process of making
oakum by first reducing the fibre to the form of a roving or a long loose puffy
strand of fibres practically uniform throughout its length, and then applying the tar
to this strand.
To manufacture the improved yarn according to this Invention the doubling and
drawing of the sliver is many times repeated in order to make the fibres even and
until the sliver has become so fine that any further drawing will break it. The
sliver is then taken to the slubbing frame, and is there given a slight twist which
tightens the fibres, causing the slubbing, as the yarn is now called, to be a little
more firm than the sliver. Up to this point the process does not differ from that
ordinarily used in spinning cotton.
I now take one or more of these cotton slubbings (according to the size of yarn
required), which are still very coarse, and twist them very hard. The article thus
produced, although in the form of a coarse strand or yarn, is worthless without
further treatment for any purpose known to me, as it will kink badly and untwist
unless it be very carefully treated and kept under tension, but if it be carefully
treated, as for example maintained under a tension sufficient to keep it from kinking
and untwisting, and is passed through a bath of boiling tar so as to saturate the
fibres, all tendency to kink and untwist will be removed, and a firm strong yarn
will be produced ordinarily adapted for rope making and other purposes, each fibre
being connected to the adjoining one. It will be advisable to add to this tar bath
an extract of some tanning substance, such as fustic, turmeric, oak-bark, and gambia,
first boiling one of these substances, as for example fustic, in water until its tanning
and colouring properties have been extracted using very little water in proportion
to the amount of fustic in order that the extract made may be very strong), then
mixing this extract with boiling tar in the proportion of one part in bulk of extract
to three parts of tar. The twisted slubbing is passed through the bath in the
manner well known to all skilled in the operation of tarring rope yarns, and is then
passed over. dryers, so that a dry, fine, and strong yarn is formed, which is very

page_text: strong yet very soft, and is well fitted for use as a twine for forming a backing for
carpets or for twisting into ropes.
The fibres are firmly attached together and made water-proof by the tar, and in
case the tanning extract is added to the bath they are strengthened and preserved
thereby, and there is no danger of the yarn untwisting or becoming kinked. This
yarn is much lighter and stronger than a hemp or flax yarn of the same size, and
owing to its softness and flexibility will wear very much longer than a hemp or flax
yarn of equal size; it is less elastic than an untarred cotton rope, and is therefore
much more useful; moreover it can be made at much less expense. The addition
of the tanning extract to the tar bath is not necessary, but is desirable, the
essential feature of my Invention being the twisted and tarred cotton yarn.
Having thus fully described the said Invention, as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it under-
stood that I claim,-
First. The manufacture of tarred cotton oakum composed of a roving of cotton
saturated with tar, substantially as above described.
Second. The manufacture of yarn formed by twisting a slubbing (or small strand
of cotton of uniform size throughout its length, and with the fibres parallel) into a
coarse yarn, and then passing the twisted yarn under tension through a bath of
boiling tar, the twisted fibres being connected together, and the twisted Blubbing
prevented thereby from kinking and untwisting, as above specified.
Third. The improvement in the manufacture of oakum consisting in first
reducing the fibre to a roving and then applying the tar, substantially as herein
described.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, the Twenty ninth day of October, in the year of our Lord
One thousand eight hundred and seventy nine.