Thread Path of Single Needle Sewing Machine: Easy Guide

Introduction

A single needle lock stitch Industrial sewing machine is a common sewing machine. It is one of the most widely used machines in the garment industry. So, this article explains the thread path of a single needle lock stitch industrial sewing machine easily. The correct thread path is crucial for manufacturing a good-quality seam of the garments. If the correct thread path is not followed, different stitch faults occur. For example, skipped stitches, puckering, and uneven stitch formation etc. However, let’s learn the thread path of single needle lock stitch sewing machine from the bobbin holder to the needle.

How to form a lock stitch in a single-needle sewing machine

A single needle lock stitch sewing machine uses two sets of thread to produce a lock stitch. One set is called needle thread, and the other set is called bobbin thread. The needle thread forms a loop below the fabric. The shuttle catches this loop and interlocks it with the bobbin thread. There are three basic elements required to produce a lock stitch. They are:

1. Needle thread
2. Bobbin thread
3. Shuttle mechanism

Generally, single needle lock stitch machine is used for the 301 stitch type. Stitch type 301 is one of the most common stitch types in the garment industry.  

You can read: Mechanism of Lockstitch Formation with Dynamic Image

Graphical view of sewing thread path

A= Bobbin	B= Upper guide
C, D= Middle guide	E= Tension regulator
F= Tension spring	G,H= Guide
I= Take-up lever	J= Lower guide
K= Hole in the needle bar	L= Needle eye

Thread path of single needle lock stitch industrial sewing machine

The threading path of a single-needle sewing machine is given below:

1. Cone: Sewing thread path starts from the thread cone or spool mounted on the thread stand. Sewing thread is pull from the cone or spool and pass through the guide.
2. Upper thread guide: after leaving the thread from cone or spool, the thread passes through the upper thread guide. Thread guide controls the direction of the thread.
3. Middle thread guide: Then the thread is passed through the middle thread guide of the sewing machine.
4. Tension regulator: The next step, the thread is passed between the two tension discs.  These tension discs control the amount of tension applied to the sewing thread.
5. Tension spring: subsequently, the thread is passed through tension spring. It is called tension check spring. It also controls small amount of thread tension during the stitch formation of sewing machine.
6. Guide: then the thread is pulled through the guide.
7. Take-up lever: the next step of sewing threading, the thread passes through take-up lever. It moves up and down during machine operation. It controls the amount of thread supplied to the needle.
8. Lower guide: from the take-up lever of the single needle sewing machine, the thread is pulled down through the lower guide of the machine.
9. Hole in the needle bar: then the thread is pull down through the hole in the needle bar.
10. Needle eye: Finally, the sewing thread path is ended by passing the thread through the needle eye. Remember, sewing thread should pass through the needle from left to right.

You can read: Mechanism of Chain Stitch Formation with Dynamic Image

Why the correct thread path is important

Garment factories mostly use single-needle lock stitch machines. So, the correct hreading system should be known by both the operator and the apparel professional.

1. Correct sewing thread path helps to maintain consistent stitch quality.
2. It also helps stabilize thread tension.
3. It reduces thread breakage. So, the production rate of garments increases.
4. A correct sewing threading increase higher sewing efficiency.
5. It reduces alternation and rejection of garments.

Conclusion

The sewing thread path of a single needle lock stitch industrial sewing machine is a basic part of sewing machine operation. It provides stable tension, proper stitch formation as well as overall performance of the machine. This article try to describe the sewing thread path easily step by step. If you have any questions about single needle lock stitch industrial sewing machine, drop them in the comments box.