TYPES OF KNITTING YARNS
The qualities necessary for knitted goods have already been outlined as
applied to the fabric, but if ideal results are to be secured, the yarns
require to possess certain specific features of their own, for the most
efficient textures can only be got by combining the qualities of yarn
and fabric. The range of yarns covers a wide variety of material and
systems of manufacture and the type selected depends entirely on the use
to which it has to be applied; price is its primary consideration, and
whether required for outer, intermediate or under garments is also
important. Speaking generally, the knitting yarn should be open in
texture, full in handle, and the material should be soft and comfortable
to the touch. Except for some classes of outer wear the thread should
have a plentiful proportion of surface-projecting fibres which are of
value in covering raw loop formation.
_Woollen Spun Yarns._—Yarns spun in the woollen system are still used to
a considerable extent in the knitting trade, such having large scope in
the more moderate priced qualities. The yarn is produced by the ordinary
methods of woollen yarn spinning, the wool being teased, scribbled,
carded, condensed and spun into threads on the woollen mule. The
combined effect of these operations is to give a yarn which has its
constituent fibres crossing and re-crossing at every angle so as to give
a melange of fibres, confused at first sight only because these are
arranged in a yarn regular in diameter and compact in structure. Carding
and spinning are done in the grease so that goods made from them require
a more liberal scouring and fulling. The best known type in the coarse
variety of woollen-spun yarns is, perhaps, the wheeling, which is
illustrated by means of photo-micrograph, Fig. 21, and given in the form
of two-ply, but large numbers are used in three or more ply for goods of
the coarsest gauge. The name Wheeling is probably derived from the early
days of hand spinning on the wheel when the wool grown on the farm was
dealt with by the farmer's daughter by means of the distaff and spindle.
In this type of yarn the wool fibres were spun as they hung on the
distaff, and the chief care of the spinster was to draw them out so as
to present as even a strand as possible to the torsion of the whorl. The
single yarns were therefore rather irregular, but these deficiencies
were to a large extent overcome subsequently by folding two or three
plies according to the weight desired. In the days of hand spinning it
was deemed most easy to specialize in one uniform thickness of ground
thread and obtain the thicker counts by twisting these threads two or
more ply. The wheeling yarns as made to-day partake very much of the
same character; they are spun from the coarser grades of wool where long
and short fibres are used promiscuously, all of which features may be
noted by an examination of photo-micrograph 21 which gives the thread
original magnified forty-fold. Fig. 22 gives a similar enlargement under
the microscope of a yarn of the same class as used for utility wear at a
moderate price, this yarn is three-fold and is spun on the woollen
system with fibres showing in every variety of angle. The three-ply yarn
shows very dense and gives a garment in a coarse gauge with considerable
weight and of most serviceable character; it is found very adaptable for
thick woollen socks for artisan wear.
[Illustration:
FIG. 21
]
[Illustration:
FIG. 22
]
_Lamb's Wool Yarns._—The term lamb's wool as used in the knitting
industry does not confine its connotation to the product of the lamb
during its first six months of growth, although such yarns would
naturally be included in the first scope of the term. Naturally the
growth on the lamb during the first half-year is of the softest
description and greatly esteemed for many classes of knitted goods where
a kindly feel is of the utmost value. The term has to-day a much wider
definition, and includes yarns spun from the shorter staples on the
woollen system, so that such goods are well covered with surface
material and further offer a good basis for brushing on the teasles or
gig, thus increasing the softness considerably. Fig. 23 gives a
photo-micrograph of one of the finer classes of lamb's wool yarns where
the crossing and re-crossing amongst the constituent fibres is very well
displayed along with the loose open form of the thread. The openness of
texture proclaims this variety as being eminently suitable for the
underwear branch of the business and these made into garments of
moderate price give excellent service. In this sample the fibres are
very regular in diameter, the thread is well constructed and will be
sound in respect of absorbent quality.
[Illustration:
FIG. 23
]
_Shetland Yarns._—This is another example of a designation employed in
the knitting trade which has wandered far from its original meaning. The
name has primary reference to yarns and fabrics produced from the
material taken from the Shetland breed of sheep which give wool of
excellent soft handling properties. These wools occur in natural
colours, brown, grey and black being found in addition to the
predominating white. The fibre is soft, exceedingly agreeable to handle,
and has been largely used for the industry from the pioneer days of the
hand knitting. The word Shetland as now known in the trade has shown a
distinct tendency to deteriorate in connotation and most generally means
yarns of coarse character, carded and spun on the woollen system with a
certain proportion of fibre of nondescript character mixed. These fibres
are usually dark in colour and mixed along with the white wool give a
tint known as "Natural"; the tints are most serviceable for utility
undergarments in regular wear as they obscure soiling and allow of
longer inter-laundry periods. Pure white articles are quickly soiled,
the "Natural" garments can give a longer period of usefulness without
sacrificing real cleanliness. In times of scarcity of material and in
absence of laundry facilities, these natural coloured garments prove
distinct aids to economy. Formerly the natural tint in a garment was at
once a sign of inferiority and low grade, but now wools of expensive
character are mixed with 5 to 10 per cent. of freshly-dyed fibre of
pleasing effect to give better service. There has latterly been a
tendency to increase the proportion of dark-coloured fibres and give a
wider colour expression; in place of the ordinary brown, fawn and grey,
other varieties bolder in aspect are utilized.
[Illustration:
FIG. 24
2-PLY SHETLAND NATURAL YARN SHOWING DARK FIBRES INTERMIXED
]
_Fingering Yarns._—The term fingering is widely known in the trade and
is a clear reference to the era of hand spinning on the wheel when the
fibres were drawn through the fingers preparatory to the addition of
torsion, this "fingering" being a domestic attempt to establish a
certain amount of parallelism amongst the fibres. Wools of longer staple
were employed for these productions which may be regarded as the
prototype of the modern worsted thread. The attempt to render the fibres
parallel by hand cannot be completely successful, but the worker
rejected the shorter material which was not incorporated in the thread,
whilst the longer residual fibres were spun with rather more twist than
was usual with pure woollen yarns. The fingering yarn as now known is
spun from the better classes of medium-stapled wool and is usually found
in three or four-ply for the better class woollen hose trade. It gives a
good quality article which felts less than the woollen spun and has
increased durable qualities, the three-ply giving a considerably
augmented strength to the article. The principle of worsted spinning as
practised in the Bradford district for weaving yarns is not suitable for
the knitting industry. As a rule the twist is too hard, and even with
slack twist the structure is scarcely suitable, not being open enough
and having too little surface fibre. A fingering yarn largely used for
the footwear trade is given in photo-micrograph at Fig. 25, where the
thread is noted to be three-fold; the single strands show a firm twist,
but at the same time there is visible a fair percentage of surface
material which makes the yarn suitable for covering the interstices and
contributing to fabric consistency. The qualities of this particular
yarn have been tested by long experience in use and have proved ideal
when the right kind of wool is used as foundation.
[Illustration:
FIG. 25
]
[Illustration:
FIG. 26
]
_Worsted Underwear Yarns._—A view of a typical yarn as used for the
light-weight underwear branch of the knitting business is given in Fig.
26, which represents a two-fold hosiery yarn used for light-weight
shirts and pants, but more particularly for ladies' garments. Extreme
fibre parallelism is the chief feature of this yarn structure, the
fibres being meticulously pulled into line with each other by the teeth
of the comber. The next points important to observe are the spaces shown
between the individual fibres which ensure adequate ventilation and
absorbency, along with the requisite elasticity. The twist in the single
is very slight and the strength is obtained by folding the two single
strands together. At the same time a sufficiency of surface material is
present to insure correct cover for the loops so as to remove rawness of
structure and impart a "skin" to the cloth.
The yarns illustrated in micro-photos 27 and 28 may be regarded as
typical structures employed for the great bulk of the trade in
underwear, these being samples of the widely-known dry-spun yarns on the
French system. As compared with the method of producing worsted yarns in
the weaving trade, this system of dry spinning is so called because no
oil is added to the sliver in preparation; the system of combing adopted
deals with shorter and less valuable wools and moderately priced yarns
are feasible. Openness of character is best secured by imparting twist
on the ordinary woollen mule, where the thread is torsioned
intermittently in long lengths, during which operation a certain
proportion of the fibres are thrown to the surface, as clearly shown in
Fig. 27. The yarn is two-ply with a fair twist in the two-fold, whilst
the singles have quite a small amount of torsion. The extraneous
material prominent in this sample 27 is a valuable feature in the
success of the yarn for the knitting trade. Fig. 28 gives a view of a
thread of the same character but rendered denser in form on account of
its three-fold character. This is an excellent sample of a yarn giving
splendid service in wear and the production of which has caused a most
flourishing spinning industry to be established in continental
countries.
[Illustration:
FIG. 27
]
[Illustration:
FIG. 28
]
In this prosperity it is hoped the British spinner will participate more
fully in the future, because it is a branch which lends itself to
enormous production on a large scale, the usual way of doing the trade
being for one mill to concentrate on few counts so as to have a minimum
alteration in the setting of machinery. In addition the spinner requires
to instal the right kind of combing plant which, it is satisfactory to
learn, can be made very efficiently in this country; the British machine
builder has risen to the occasion, and it is to be hoped that the
spinner will follow quickly in his wake and prove equal to the enormous
call for this class of yarn. These yarns are often referred to in the
trade variously as botany yarns, or cashmere yarns, although the latter
is in reality a misnomer, having original reference to the product of
the Cashmere goat indigenous to the Himalaya Mountains in Northern
India.