How to calculate sewing thread consumption and costing

In textile sector, sewing thread required to assemble garments parts or seam sewing, label attachment, buttonholing, over locking etc. It’s important to know that how much sewing thread used to stitch the garments product. Now- a- days, garments sector is going to be competitive marketplace in globally. Every manufacture company is trying to reduce their cost of production to get the order from buyer and maximize their profit. As a part of merchandising activity, we have to control total manufacturing cost of a product to optimize more profit from an order. Sewing thread is one of the accessories items, where we can reduce or minimize the cost of a product in bulk production. Calculating the right way of sewing thread consumption, we can reduce the manufacturing cost of a garments product.

In several way, we can determined sewing thread consumption for a garment product. To calculate the consumption of thread in a seam;

• You can measure the actual amount of thread consumed in a specific length of seam.
• Can be measure the consumption by using mathematical stitch formulas based on thickness of seam and number of stitches per inch.

If we reduce or minimize the cost of garments, manufacturing company will gain more profit from bulk production. As sewing thread is one of the common accessories in garments industry, here we can minimize the cost for a product. Means, control more production losses will gain more profit from an order. By minimizing the sewing thread for a particular order, not only saving the money, but also save warehouse maintenance cost in garments industry.

Sewing thread consumption means, how much thread we used for making a cloth in garments industry. To estimate sewing thread consumption for a garment, there is many way to do that. We will use standard formula to calculate the thread consumption for a garments. By using standard formula, we will get multiplied factors according to machine type and stitching classes. Length of seam depends on the following factors for actual sewing thread consumption;

1. Classes of stitch
2. Stitches per inches (SPI)
3. Fabric thickness of the seam
4. Thread tension
5. Sewing thread count

By using manual way, we can also calculate machine wise thread consumption for a garments. It will be great if garment thread calculate manually by yourself. By following below step, we can develop multiplying factor according to product categories.

To calculate thread consumption, you need a sewing machine, fabric and thread that will be used in bulk production. For fabric and thread, we can take similar thickness and thread count for calculating consumption of thread.

Now sew a seam of 12 inches long and take 1 inch to manually check the consumption. After getting the consumption, add thread wastage 10-15% for smooth production.  

Find the below chart for quick action & machine wise estimate sewing thread per inches given below-

Machine Uses	Need thread per inch stitching
Plain Machine – Single needles	2.75 inches
Plain Machine – Two needles	5.5 inches
Over lock Machine – Three threads	15 inches
Over lock Machine – Four threads	18.75 to 20 inches
Over lock Machine – Five thread	23 inches
Safety stitch	20 inches
Flat lock Machine	22 inches
Chain stitches – One needles	12.5 inches
Chain stitches – Two needles	25 inches
Button Hole	24 inches
Bar take machine	26 inches

Sewing thread consumption calculation is one of the most important task in garment industry. So, garments merchandiser must have proper knowledge to calculate the sewing thread consumption. Otherwise, sewing thread may short during bulk production or will stock thread because of excess booking. During booking of sewing thread, merchandiser have to calculate thread properly and place the work order as required.

Using above estimate machine wise thread consumption, we will see how to calculate sewing thread costing, how to calculate thread consumption, how much will save. Suppose, Buyer C&A place a T-shirt order for kid’s with below details;

• Total 4 thread over lock (O/L) – 55 inches
• Total flat lock used (F/L) – 35 inches
• 2 needles chain stitches used – 25 inches
• Plain machine (P/M) one needle used – 40 inches

Total consumption for T-shirt –

(55” x 4 thread O/L) + (35” x F/L) + (25” x 2 needles chain stitches) + (40” x One needle P/M)

= (55” x 18.75) + (35” x 22) + (25” x 25) + (40” x 2.75)

= 1031 inch + 770 inch + 625 inch + 110 inch

= 2536 inches

= 2536 inches / 39.37 = 64.4 Meter (Note: 1 meter = 39.37 inches)

= 64.4 inches + (15% wastage of total consumption)

= 74 meter / body

As per above consumption, let’s find out cost of the sewing thread for this kid’s t-shirt order. Note that, maximum garments product used 100% spun polyester to stitch / attached the garments. For calculating cost of sewing thread need below information;

• Count of sewing thread
• Consumption of the body / garments
• Sewing thread unit price per cone

Suppose, a C&A buyer have kid’s order with below details and need to calculate the cost of sewing thread;

• Count of sewing thread is 50/2, 100% spun polyester
• Total thread consumption, 74 meter per body
• Sewing thread price $0.52 / cone for 4000 meter

Let’s calculate the costing of sewing thread for above kid’s order;

Unit price of cone / total meter of cone x consumption of per body

= $0.52 / 4000 x 74 meter

= $0.01 / per body

Above costing has come for one garments. If we have 150000 pcs garments for an order then total cost will be (150000 pcs x $0.01) $1500. If we calculate how many cone needed to complete total production then;

Total order quantity x sewing thread consumption per body

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                           Total meter of cone

= 150,000 x 74 / 3800

= 2912 cone

Here, we divided by 3800 meter instead of 4000 meter, because of production safety. Sometime, actual 4000 meter may not be present in the cone. So, we are using 3800 meter for safety and smooth bulk production. 

Now let’s see how much we will save, if you calculate the consumption correctly for a particular garments product. Suppose, without calculation we place the booking of sewing thread as 90 meter / body. As per consumption and order quantity, total sewing thread needed 3552 cone (for 150,000 pcs garments). That means, total cost of sewing thread is $1847 (3552 cone x $0.52). Here we can see, for a single order we can save almost $347 ($1847-$1500).