Fabric Weight Measurement Technique
Md. Shafiqul Islam (Newton)
Manager –Softlines lab, Epyllion Testing Lab Ltd,
Gazipur, Dhaka, Bangladesh
Email: newton@epylliongroup.com
FABRIC WEIGHT:
Fabric weight is a most important characteristics of a fabric. It is required to confirm about the fabric weight of a finish fabric otherwise we cannot revert when garments is made. Fabric weight measurement is also important because buyers requirement of specific GSM.
PURPOSE:
To make a representative assessment of the mass per unit area in grams per square meter of a fabric. Specifically know fabric GSM by fabric weight measurement.
APPARATUS:
- Circular Sample cutter capable of giving a specimen area of 100cm2+/- 1 cm2.
- Weight balance
- Cutting board.
Sample Cutter Check:
Check your sample cutter by yourself with a simple method. Cut a white page and fold it and measure by mm steel ruler. If it is 112.6 mm and above then your cutter is ok to get accurate result.
It is a little mathematics:
The area of a circle is calculated by multiplying the square of the radius by π (3.141592…)
So if the diameter is 113 mm, the radius will be 113/2 = 56.5. The area of the specimen you cut will therefore be 56.5 x 56.5 x 3.141592 = 100.29 sq cms.
You are looking for Grams per Square Meter. The area of
1 square meter is 100 x 100 square cms = 10,000 sq cms.
Therefore if you divide 10,000 by the area of the specimen you have cut, you will get
10,000 / 100.29
= a factor of 99.71.
Therefore if you multiply the weight of the specimen by 99.71 you will get the Grams per Square Meter. Most people multiply by 100, so, when they read the result from the balance they automatically just move the decimal point two places to the left.
As an illustration suppose the specimen weights 1.85grams, the GSM will be 1.85 x 100 = 185 grams per square meter.
If you multiplied by 99.71 the result would be 1.85 x 99.71 = 184.46 grams per square meter.
Because of variations in the cutting performance of different fabrics the 0.29 grams does not really play a significant role in the accuracy of the test result and most performance requirements anyway give a tolerance of maybe +- 2/3%.
More articles published by this author:
- Factors Affecting Appearance After Washing of Garments
- Phenolic Yellowing Test Method in Textile Industry
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. Mr. Kiron is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.