Measuring of Thread Consumption in a Garment
Measuring of Thread Consumption
It is important to know the amount of thread consumed in a sewn product so you can: 1) Estimate the number of cones needed; and 2) Calculate the cost of the thread needed to manufacture the finished product. Thread consumption can be determined in several ways. To calculate the amount of thread in a seam, you can:
- Measure the actual amount of thread consumed in a specific length of seam.
- Calculate the thread consumption by using mathematical stitch formulas based on the thickness of the seam and the number of stitches per inch.
Measuring Actual Thread Consumed
A specified length of the seam, for example 3 inches, is measured and then the thread is removed by carefully unraveling the stitch. You can then calculate the amount of thread consumed in one inch and multiply this factor times the total length of the seam measured in inches.
To define thread consumption you just have to multiply seam length with that factors. Thus, one can estimate total requirement of thread for making a garments. But actual thread consumption for a unit length of seam depends on many factors.
- Stitch Classes
- Stitches per inches (SPI)
- Thickness of the seam (fabric thickness)
- Thread tension
- Thread count (thickness of sewing thread)
- Length of seam is 42 inches or 1.17 yards.
- Stitch and seam construction: 401 SSa-1.
- Specified length of thread removed from a seam equals 3 inches.
- Needle thread removed = 9 inches
- Looper thread removed = 8 inches
- Needle thread factor = 9 ÷ 3 = 3 inches of needle thread per inch of seam.
- Looper thread factor = 8 ÷ 3 = 2.67 inches of looper thread per inch of seam.
- Total needle thread consumed = factor 3 X 1.17yds = 3.51 yds
- Total looper thread consumed = factor 2.67 X 1.17yds = 3.12 yds
- Total Thread = 3.51 + 3.12 = 6.63 yards per seam.
- Generally a 10 to 15% waste factor is added due to chaining-off, thread breaks, repairs, etc.
- If a waste factor of 15% is selected then:
- 6.63 yards/seam X 1.15 = 7.62 yards/seam including 15% waste factor.
Obviously you must do this for each seam to determine the total amount of thread consumed in the finished product.