Basic Knowledge of Sewing - Double Chainstitch

Chapter 1 : "Basic Knowledge of Sewing" - Double Chainstitch

Learn about the seams that can be sewn with industrial sewing machines and the sewing problems that can easily occur.

Table of contents

• 1.1Types of Stitches
• 1.2Types of chainstitches
• 1.3Problems experienced in sewing process
• 1.4Summary

Chapter 2 ：Characteristics of the Double Chainstitch

Learn about the characteristics of double chainstitch seam shapes and how double chainstitch seams are formed.

Table of contents

• 2.1Seam shape and characteristics
• 2.2Threading
• 2.3Formation of the double chainstitch seams

Chapter 3 ：Adjustments

This course teaches how to adjust the needle bar, looper, thread spreader, needle guard, looper thread take-up cam, and feed dog which are the main adjustment points to form the seam of double chainstitch sewing machine.

Table of contents

• 3.1Needle height
• 3.2Looper action timing relative to the needle action
• 3.3Looper-to-needle distance when the looper moves forward to catch the needle thread
• 3.4Looper avoid motion
• 3.5Thread Spreader timing relative to the needle timing
• 3.6Thread Spreader position
• 3.7Needle guard and loop guide position
• 3.8Looper thread take-up cam timing
• 3.9Feed dog height and inclination
• 3.10Feed dog timing
• 3.11Sliding presser foot

Chapter 4 ：Sewing problems and stitch skipping

Learn how to identify factors and take countermeasures when stitch ploblems or stitch skipping occur.

Table of contents

• 4.1The looper does not dependably catch the needle thread
• 4.2The needle does not dependably catch the looper thread (stitch skipping on the back side of the looper)
• 4.3Summary of sewing problems caused by incorrect settings

Chapter 5 ：Summary

Summary of double chainstitch.