Bachelor of Fashion Design (Knitwear Design) © 2010 www.vasantkothari.com 3 Linear Density Ō The thickness or diameter of a yarn is one of its most fundamental properties Ō However, it is not possible to measure the diameter of a yarn in any meaningful way © 2010 www.vasantkothari.com 4 Linear Density Ō This is because the diameter of a yarn changes quite markedly as it is compressed Ō Because of these problems a system of denoting the fineness of a yarn by weighing a known length of it has evolved © 2010 www.vasantkothari.com 5 Linear Density ŌThis quantity is known as the linear density and it can be measured with a high degree of accuracy if a sufficient length of yarn is used © 2010 www.vasantkothari.com 6 Tex Direct Denier Count English Indirect Worsted © 2010 www.vasantkothari.com 7 Count Determination Ō Irrespective of the system of yarn numbering employed, two basic requirements for the determination of yarn number are.. © 2010 www.vasantkothari.com 8 Count Determination ő An accurate value for the sample length ő An accurate value for its weight © 2010 www.vasantkothari.com 9 Count Determination Ō The methods determination of yarn count depend to a large extent on the form in which the yarn is available for testing © 2010 www.vasantkothari.com 10 Count Determination Ō For example ő when yarn is in form of ring bobbin a long sample length is possible ő when yarn is in form of fabric, only a number of short lengths are available © 2010 www.vasantkothari.com 11 Count Determination Yarn Form Fabric Form Length Measurement © 2010 www.vasantkothari.com Weight Measurement 12 Weight Measurement Ō Balances ő The analytical balances and any other balances used in determination of count must be accurate and calibrated time to time in order to get the exact readings © 2010 www.vasantkothari.com 13 Weight Measurement Ō Moisture ő Moisture contain can affect the results largely so it is very important to do 24 hrs conditioning of the sample in standard atmospheric condition © 2010 www.vasantkothari.com 14 Beesley Balance Ō A number of special yarn balances are available which are designed to furnish the a quick estimate of the count, especially when only small samples are at hand Ō One of such balance is BEESLEY Balance © 2010 www.vasantkothari.com 15 Beesley Balance © 2010 www.vasantkothari.com 16 Beesley Balance Ō The Beesley Balance consists of a lightweight beam pivoted on jewel bearings with a hook at one end and a pointer at the other © 2010 www.vasantkothari.com 17 Beesley Balance Ō The beam is initially levelled to bring the pointer against a datum line Ō A standard weight is suspended in a notch on the beam arm on the pointer side. © 2010 www.vasantkothari.com 18 Beesley Balance Ō A template is used to cut short lengths of yarn, the length depending upon the count system required Ō These lengths are placed on the hook until the pointer comes against the datum line © 2010 www.vasantkothari.com 19 Beesley Balance Ō The number of short lengths required to balance the beam gives the count of the yarn © 2010 www.vasantkothari.com 20 Beesley Balance Ō A template is provided to give lengths of yarn in Metric, Cotton, Linen, Wool Skein, and worsted counts Ō The balance is housed in a sheet metal case having sliding transparent antistatic glass doors © 2010 www.vasantkothari.com 21