Combing is a method for preparing carded fiber for spinning.
It separates out the short fibers by means of a rotating ring or retalinear
row of steel pins. The fibers in the 'top' it produces, have been straightened
and lie parallel to each other. When combing wool, the discarded short fibers
are called noils, and are ground up into shoddy.
The circular combs used have long metal teeth, and only barely resemble
the comb used
However, they are used in a similar fashion with one comb holding the fibre,
which is slowelly dubbed in by a brush, while the other is moved through,
slowly transferring the fibre to the moving comb.
The rectilinear comb uses a circular comb to comb out the fringe and remove
short fibre (set by a scale so fibers less than for example 25mm are removed
) not held by a clamping mechanism. The Top comb is a very fine tooth comb
for example 25teeth per inch to act as an impediment to contaminates (Burr,
seed ect.) flow. The circular combing without shot fibers are placed on
a moving belt. The of circular combing and top comb insertion is repeated
and combed fibers - now called tuft are overlapped. The overlapping produces
some cohesion allowing the tuft then to be twisted to form a combed sliver.
This sliver is weak and unsuitable for spinning. To allow spinning to take
place additional gilling is required( Sokolov 1994 ).
Combing the fibers removes the short fibers and arranges the fiber in a
flat bundle, with all the fibers going the same direction. This preparation
is commonly used to spin a worsted
yarn. Woolen yarns
cannot be spun from fibre prepared with combs, instead the fibre must be carded.
Cotton is combed when it is to be used for quality fabric with high thread
In general, combing is done to remove the short length fibers. For example
fibre shorter then 21 mm. The comb is a filter or sieve for short fibre
worsted. In process of combing carding is a primary process followed
by 3 gilling machining. The gilling process is there to remove hooks and
involves 3 separate machines. Combing removes short fibre content as sated
earlier. The Combing is than followed by 2 gillings to remove irregularity
in the sliver and randomize fiber ends. This post combing process is required
if spinning is to follow. It is know that a sliver can be spun to a yarn
of only 21 fibers with a suitable average length of say 150mm (CSIRO 1990).
Combing is a mechanical sieve and will not remove any containment that looks
like a fibre being combed. That has to be mended out from a final garment.
The manual mending out is a costly process.
There are two competing combing technology - Noble (1853) Comb ( variants
Lister, Heilman (1846) and Holden) and French Comb. Noble comb technology
is inefficient hence most combing in world is carried out on French system.
The French system is superior as it combs' and entire length of a fibre.
Noble comb suffers from a problem that it will not comb 2mm of a fiber length.
The 2mm is distance between counter rotating pins. The French system is
a rectilinear combing system as oppose to earlier woollen system developed
in England. Although Heilman and Noble comb was original circular design
( also developed in min and 18-19th century England ) as it happens in modern
history, English mills didn't share technology - resulting in development
of superior technology on the continental Europe in mid 19th century- France.
Efforts was made by Bradford to study the mechanism of noble combing but
it failed to produce tangible results..The Noble and French combs are now
well understood technology thanks to work by CSIRO. Post 1994 Sokolov has
endeavored to improve combing performance in rectilinear comb. Post 20th
century effort in combing technology.
In cotton manufacture, the
Heilmann comber was superseded by the Naismith comber. In worsted a Noble
comber was a common make.
Noble comb is no longer used in worsted system as technology is inefficient.
Noble comb may have uses for
woolen system or long
fibers 250mm+. Predominate technology for all fibers is a French Comb system.
A cotton comber is scaled version of a rectilinear comb relative to a mean
fibre length (similar to Naismith comber). This can scaled version can be
seen in stroke of the components to accommodate fiber length and fibre physics
will add more to this topic soon with mechanics and sketch of processing