Monday, 8 May 2017

Details about yarn count and cashmere fibres

(Numero) Metric Count - nm (Metric)

This is a term used for many yarns as an alternative to a wc (much
like stating km and miles). The count is based on the number of 1000m
(metre) units in a kg (kilogram) of yarn.

All counts have two numbers - one is the count and one is the number
of strands (or ends) that have been twisted together to create that
yarn. A single yarn where you can't untwist it may not be listed with
a second number, but would technically be /1 as there is just one
strand. Roving yarns, some slub yarns or loop yarns would fall into
this category, but most yarns have a number of single ends twisted
together to create a thicker yarn and they will be stated as /2, /3,
/4 etc.

As a general rule of thumb the finer the yarn the higher the count
number (see below for why) and metric counts usually are expressed
with the count first then the ends - 30/2nm whereas cotton and worsted
counts tend to have the ends first then the count - 4/8cc or 3/9wc.

Without putting any of the above into context it doesn't really help,
so here is more of an explanation (and it's much easiest to explain
with metric counts as the numbers are nice and round - 1000, but the
same principle applies to cotton and worsted counts too):

If a yarn is stated as 60/2nm (such as our Regency Silk) it means that
there are:
60 lots of 1000m per kg (see nm count above) i.e. 60,000m per kg. If
the yarn was expressed as 60/1nm then a kg cone would have 60,000m
wound onto it.
But it has a /2 which means there are two strands twisted together so
the length is halved - it has 30,000m per kg. If it had a /4 then the
60,000 would be quartered and there would be 15,000m* per kg.

In a nutshell that's it!

*Some of the meterages may not half or quarter down exactly as there
is a bit of "take-up" widthways across the yarn but at thinner weights
this is negligible.

The above information explains why it's so important to have the count
terminology (cc, nm or wc) when asking of referring to a yarn
otherwise it's almost impossible to ascertain the correct yarn.

For a very comprehensive explanation of counts here is a link to a
fabulous book called "Yarn Counts & Calculations" by Thomas Woodhouse
1921 that someone has taken the trouble to scan and upload. It is
extremely detailed and I must admit that I have just had a bit of a
skim read of some sections and there is a lot of algebra and maths,
but it just goes to show how complicated counts, twists and plys are.

Whilst I was scouring the internet for information for this page I
also came across the brilliant article (find it here) which helps
weavers to calculate yarn requirements for plain weave weaving
projects. It also shows how and why ends per inch is important and is
written in a very simple, funny way - well worth a look.

For an "at a glance" guide here is a table of how we have split the
yarns on our website. It gives you a rough idea of counts, how many
metres to expect per 100g and what the ends per inch will be:

121/2nm & Finer6001m +100 +
4/2nm & Thicker< 219m< 11

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