Thread Consumption Methods 

In today’s competitive marketplace, there is a need for tight cost control. A realistic estimation of potential thread requirements for particular garment styles or contracts will not only end up saving you money, but also enable you to use a superior thread for the same cost, thereby not compromising on garment quality.Several factors determine the extent of thread consumption in any sewn product, such as stitch type, seam type, material thickness, number of layers, construction and SPI (stitches per inch).However, these factors are not constant with the different style preferences. Hence, thread consumption is never standard for sewn product categories such as shirts, trousers and footwear.There are two methods generally used to calculate the amount of thread in a seam and hence the thread consumption in the sewn product:

1. By measuring the actual amount of thread consumed2. By calculation using thread consumption ratios

1.     Measuring Actual Thread ConsumedA specified length of a given seam is measured and then the thread is pulled out of this length. We can use the amount pulled out of this specified length to calculate the ratio of thread consumed in the entire seam. By dividing the amount of thread by the seam length, we get the ratio of thread consumed. If we multiply this factor times the total length of seam, we can determine the total thread consumed for that seam.

Example:Length of seam = 100 cm (1 metre) Stitch class 401 = 2-Thread Chain stitch Length of seam for which thread is removed = 15 cm Needle thread removed = 19.5 cm Needle thread factor = 19.5/15 = 1.3 Looper thread removed = 62.0 cm x 1.3 Looper thread factor = 62.0/15 = 4.1 Total Needle thread = 100 cm x 1.3 = 130 cm Total Looper thread = 100 cm x 4.1 = 410 cm Total thread consumed = 130 + 410 = 540 cm Add 15% wastage* = 540 cm x 1.15 = 621 cm*Generally, 10% to 15% wastage of thread is added to the consumption derived. This wastage occurs due to shop-floor conditions like machine running, thread breakage, repairs, etc. The above example shows the total thread consumed for one type of stitch class in a garment. By following a similar procedure, you can calculate the thread consumed for different stitching operations in a garment.

2.    Thread Consumption RatiosThe easier method is to use the generally applicable Thread Consumption Ratios for the various stitch types that are listed in the table below. By relating these ratios to the length of seams using each stitch type, total thread consumption can be calculated.

Note:1. The above ratios are arrived at with a stitch density of 7 stitches per cm (18

stitches per inch).2. These ratios are the prescribed minimum in regular conditions and marginally

vary with the factors affecting thread consumption.3. A certain percentage of wastage is to be added to the above ratios as per shop

floor conditions. It may vary from 10% to 15%.

Example: Length of seam = 100 cm (1 metre) Stitch class 401 = 2-Thread Chainstitch From the table, total thread usage per cm of seam = 5.5 cm Total thread consumption = 100 cm x 5.5 = 550 cm Estimated Needle thread = 550 x 0.25 = 138 cm Estimated Looper thread = 550 x 0.75 = 412 cm Add 15% wastage = 550 cm x 1.15 = 633 cm of thread per seam

By applying thread consumption ratios in a manner similar to the calculation in the above example, a sample consumption working for an average sized knitted t-shirt is shown in the table below.ExampleThread consumption for an average-sized knitted t-shirt

These days, thread consumption and costing can be calculated without the need to pick the thread from seams. Coats' Seamworks is a sewing management software solution that can accurately calculate thread consumption and costing for a single sewn product or production run or any number of sewing machines. Seamworks helps to reduce thread wastage and can give you a competitive edge through cost effective sewing thread procurement. Ask your local Coats contact about Seamworks.Note: Stitch density, stitch / seam chioce, variations in style, fabric thickness and number of plies are factors that can affect thread consumption. It is also necessary to make provision for possible thread wastage (usually 15%) while calculating thread consumption.

Average Thread ConsumptionThe table below gives the average thread lengths consumed for different types of garments, drawn from our experience. These figures include 5% wastage allowance:

Coats Seamworks™ Apart from the two regular methods that are used, there is a quick, simple and efficient option available to our customers called Coats Seamworks. Using this software, it is possible to calculate thread consumption metering and costing without having to pick up the thread from the seam.Seamworks is a sewing management software solution that can calculate thread consumption for any sewn product.  Not only does it calculate the consumption for a single product, it also enables you to choose the right thread ordering pattern, which is necessary for optimal usage of the ordered thread in the shop floor. Salient features:

Easy-to-use familiar Explorer-type interface Support for metric and imperial measurement systems Increased data integrity Enhanced calculation engine Multi-lingual support

Fixed Weight and Fixed Length Numbering SystemsAll numbering systems used to indicate thread size are either ‘fixed weight’ or ‘fixed length’ systems.

 Generally, Metric count is used to describe synthetic, spun and core spun thread while English count is used to specify cotton thread. Filament threads are normally expressed with Decitex or Denier. 

Resultant Thread SizeWhen more than one ply of yarn is twisted into a thread, finding the resultant size of the thread by considering all the plies becomes necessary. In fixed weight systems: Resultant size = Individual yarn count / Number of plies In fixed length systems: Resultant size = Individual yarn count x Number of plies A particular resultant size can be made with any number of plies. Count Conversions Using the table below will enable you to perform a simple conversion from one system to another. 

 

Ticket Numbering Ticket numbering is a commercial numbering system. Ticket numbers are merely the manufacturer’s reference numbers for the size of a given thread.The Metric Count, Cotton Count and Denier Systems use ticket numbering system to give an easy approximation of the specific size of the finished thread.A ticket number in one type of thread will not be the same as in another. For example, Ticket 40 Cotton is not the same as Ticket 40 Corespun.Ticket numbers resemble the fixed weight system. They can simply denote:Higher the ticket number, finer the thread.Lower the ticket number, thicker the thread.Converting sizes for synthetic products

Arriving at a Ticket Number 

 Note: • To convert any Tex Number to a Ticket Number value: divide 1,000 by the Tex number and multiply by 3. • To establish the Tex of a particular Ticket number, please contact your nearest Coats office.Cotton threads are rarely used today, so ticket numbers for cotton threads are not discussed here. Communicating Thread Size with Ticket Numbers In the thread industry, different countries follow different ticket numbers. Knowing different ticket number conventions for a certain thread size and the corresponding Tex size will aid you in thread selection. Ticket numbers of three different Coats threads specified by different ticketing systems are given in the tables that follow. 

Different Ticketing Systems – Polyester / Cotton Corespun (Coats Dual Duty)

 

Different Ticketing Systems – Polyester Corespun (Coats Epic)

  

Different Ticketing Systems – Staple Spun Polyester (Coats Astra)

To Convert From To Multiply by

Threads in Fabric:Number per inch

Number per centimetre 0.3937

Stitches in Fabric:Number per inch

Number per centimetre 0.3937

Mass per unit area:Ounce per sq. yardGram per sq. metreMomme

Gram per sq. metreMommeOunce per sq. yard

33.9060.230.128

Twist LevelTurns per inch

Turns per metre 39.37

Dimetre1/1000 inchinchinch

Micrometremillimetrecentimetre

25.425.425.4

Cover Factora. Woven cotton fabrics

b.Weft knitted worsted fabric

0.957 

1.172

Twist factor (or multiplier) 9.57

Gram forcePound ForceKilogram Force

MillinewtonNewtonDecanewton

9.814.450.98

Tearing StrengthPound Force

Newton 4.45

TenacityGram force per denier

Millinewton per Tex 88.3

Bursting PressurePound force per sq.inch

Kilonewtons per square metre 6.89

 

Conversion Factors for Common UseTo Convert From To Multiply by

LengthInches(in)Feet(ft)Land miles(=5280 ft)Nautical miles(=6080

Centimetres(cm)Metres(m)Kilometres(km)Kilometres(km)

2.540.30481.6095441.85327

ft)AreaSquare inches(in2)Square feet(ft2

Square milesAcresAcres

Square centimetres(cm2)Square metres(m2

Square kilometres(km2)Square kilometres(km2)Hectares(ha)

6.4520.0929032.589990.0040470.404686

Capacity/VolumeCubic inches(in3)Cubic feet(ft3))UK gallonsUS gallonsQuartUK pintUS Pint

Cubic centimetres(cm3)Cubic metres(m3)LitresLitresPintMilliletres(ml)Milliletre(ml)

16.3870.02854.5463.7852568473

Weight/MassOunces(oz)Pounds(lb)Long tons(=2240 lb)(=1.016 tonnes(t))

Grams(g)Kilograms(kg)Kilograms(kg)

28.34950.455591016.05

TemperatureFarenheit(F)

Celsius/Centigrade(oC) (F-32) & 0.5555

LengthCentimetres(cm)Metres(m)Kilometres(km)Kilometres(km)

Inches(in)Feet(ft)Land miles(=5280 ft)Nautical miles(=6080 ft)

0.39373.28080.621370.53961

AreaSquare centimetres(cm2)Square metres(m2)Square kilometres(km2)Square kilometres(km2)Hectares(ha)

Square inches(in2)Sqaure feet(ft2)Sqare milesAcresAcres

0.15510.76390.3861247.105247.105

Capacity/VolumeCubic centimetres(cm3)Cubic metres(m3)LitresLitresPintMillilitres(ml)Milliletres(ml)

Cubic inches(in3)Cubic feet(ft3)UK galonsUS gallonsQuartUK PintUS Pint

0.0610235.31470.219970.26420.50.001760.00211

Weight/MassGrams(g)Kilograms(kg)Kilograms(kg)

Ounces(oz)Pounds(lb)Long tons(=2240 lb)(=1.016 tonnes)

0.035272.204620.00098

Temperature Farenheit(F) (oC * 1.8)+ 32

Celsius/Centigrade(oC)

 

1. Reed CountIt is calculated in stock port system.No. of dents in 2 inches is called Reed Count.Reed Count = EPI/(1 + Weft crimp %age)

2. Reed Width Reed Width = Cloth Width *(100+ weft crimp %age)/100

3. Crimp PercentageCrimp %age = {(Warp length - Cloth length)/Cloth Length}* 100Crimp %age = {(Warp width - Cloth width)/Cloth width}* 100

4. Cloth Cover Factor

a.

b.

c. Cloth Cover Factor = Wp.C.F +Wt.C.F. - {(Wp.C.F. - Wt.C.F)/28}5. Maximum EPI for particular count

a.

b.

c.

d. other design = (Ends /Repeat * 1/Yarn Diametre)/ (No of intersections/repeat+ ends/repeat)

e.

6. Warp Density

                            = <350

Weave Density = 50+{(Warp Density - 100) * F.D - 100} /{(Weft Density - 100)* F.D - 100}

Effective Weave Density = W. D x K of loom width x K of Design                                     = < 72

Wp / filling - K  Loom Width - K  Weave Design - K

Cotton = 1.00 140 cm - 0.99 Plain1/1 = 1.00Polyester/Cotton = 1.03 180 cm - 1.00 Twill 1/2 = 0.87Viscose Filament = 1.17 190 cm - 1.01 Matt, Gabardine 2/2 = 0.82Polyester Filament = 1.22

220 cm - 1.02 Drill 1/3 = 0.77

250 cm - 1.08 Satin 1/4 = 0.69330 cm - 1.15360 cm – 1.20

7. To change the count and the number of thread / inch , keeping the same denseness of fabricTo change the count without altering the denseness of the fabricEPI in Exp.cloth = (EPI in exp.Cloth2/EPI in given cloth) * count in given clothTo change the EPI without altering the denseness of the fabric

8. Warp requirement to weave the cloth Warp weight in grams /metre = {(Total Ends * 1.0936 * 453.59 * crimp %)/(840 *

count)} * wastage % Weft weight in grams /metre ={(R.S. in inches * 453.59 * PPI)/(840 * count)} * wastage

% * crimp % Cloth length in metres with given weft weight=( weft weight in kgs * weft count * 1848 *

0.9144)/(PPI * R.S in inches)

For silk and Polyester

Warp weight in grams /metre ={(Total Ends * count (Denier) )/9000} * wastage % * crimp %

Weft weight in grams /metre = {(R.S in inches * count(Denier)* PPI)/9000}* wastage % * crimp %

Allowance for count in bleached and Dyed fabric1.Count becomes 4%2. FinerDyed counts become max 6% Coarser

9. Fabric Production Calculation

Loom Speed = Motor RPM * (Motor Pully Diametre)/(Loom Pully Diametre) Loom Effeciency Percentage = (Actual Production/Calculated Production )* 100 Moisture Regain Percentage = {(Yarn Weight - Dried Yarn Weight)/Dried Yarn weight}

* 100 Moistue Content Percentage = {(Yarn Weight - Dried Yarn Weight)/Yarn weight} * 100 

Type of Yarn Moisture Regain % Moisture Content %

Cotton 8.50 7.83Jute 13.75 12.10Silk 11.00 9.91Rayon, Viscose

11.00 9.91

Wool 17.00 14.50Nylon 4.20 3.78

10. Warp Weight in Kg = (Total Ends * Tape Length in metres)/(1693.6 * Warp Count) Weft Weight in Kg = (R.S in centimetres * cloth length in metres * PPI )/(4301.14 * weft

Count) Cloth weight in GSM = {EPI/Warp Cout)+(PPI/Weft count)}* 25.6 oz (ounce ) per sq. yard = GSM(Grams per sq. metre)/34

11. Material Measurement  To calculate the length of any rolled fabrics, this formula gives the nearest accuracy.  L = {0.0655(D-d)(D+d)}/t  Where L = Length of material (Feet)    t = Thickness of fabrics (inches)            D = Outside diameter (inches)   d = Inside diameter (inches)

12. Weight of yarn in a clothThe weight of cloth manufactured on looms depends upon the weight of yarns in thewarp and weft: ends/inch, picks/inch and the weight of size on the warp. Therefore,  Cloth weight = Weight of warp + Weight of weft + Weight of size (All inlbs.)Where as Weight of warp in lbs. = (Total No. of Ends * Tape Length in Yards)/(840 * warp yarn count)

Also