Experiment name:
Study of thread path, main adjustment points of different industrial overlock machine and production of sample.
Introduction:
There are many types of sewing machine. Some are used for special purposes such as overlock machine, bar tack machine, button hole making machine etc. Overlock machine is also called serger. A serger is an overlocker. An overlocker is a serger. This type of machines works in a cycle and so these are called simple automatic machine. Here we study on such a type of machine that is overlock machine. Overlock machines are specialized machines that make the overlock stitch. The overlock stitch is used for edge finishing and seaming. Overlock machines come in both home and industrial versions.
Fig: Overlock stitch
Objectives:
To know about the machine parts of overlock machine.
To know about the thread path of overlock machines.
Description: Mainly over edge machines are overlock machines. In this type of sewing machines there are one or two needles and edge-trimming knife is at the front of needle. To make over lock stitch 2-5 threads are used. Usually SPM of over lock machine is 6500. But SPM of 8500 machines are also found. In this machine there also stretching (stretching max 1: 0.6) and gathering (gathering max 1: 4) systems during feeding cloth. Stitch is done up to maximum 4 mm length and stitch length may also be changed by push button. This type of machines can be used for sewing for both woven and knitted cloths.
Fig: Thread path of overlock machine
Adjustments Points of Overlock Machine
Basic Machine Practice
Technical Specification
Installation of needle
Needle bar height adjustment
Needle to lower looper timing
Upper Looper Timing
Chain looper timing (Safety Stitch)
Upper Knife Adjustment
Lower Knife adjustment
Feed Dog height adjustment
Cam Timing
Thread Adjustment
Conclusion:
Overlock machines can not be used for normal purpose. But for making a complete garment their importance can not be denied. Special care and sufficient knowledge is necessary for proper working. Otherwise faulty sewing may be done. I would like to give special thanks to our teacher. I am also grateful to our instructors. I think this will be very helpful in my future life.
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.
