Lock stitch prevents sewing machine seams from unraveling or stretching at the ends. It is an alternative to a backstitch and is better for fine fabrics, and sewing darts. Lock stitch ends are less bulky and equally secure and does not change the drape on the fabric edges.
Sewing Lock Stitch Tutorial
Whenever you set your machine to make a simple straight stitch or zigzag stitch, you can start and finish with a lock stitch.
One of the most important purposes of this stitch is to secure the beginning or end of the sewing to stop the stitches from unraveling. This is a particularly good way to secure the seam on fine fabrics where a double set of stitches going back and forth would show and look ugly. Lock stitch is useful when sewing quilt blocks to reduce bulk and to make the back of the quilt more attractive.
The lock stitch, using smaller stitches, and tying a knot at the beginning and the end ensures a neat and secure finish to the starting point and the end of the seam.
Lockstitch vs Backstitch
Lockstitch gives a less bulky end than backstitch. Compare these 2 examples. See how the backstitch has the ends with 3 layers of stitching. When backstitching, you will start, go forwards and stitch a few stitches, then reverse and go forwards again.
In comparison, lockstitch has no reverse stitching. The ends are secured by tiny stitches that are hard to unravel.
Sewing Machine Lock Stitch (Automatic Lock Stitch)
A lock stitch is a built-in feature of some computerized machines. It will have the ability to start small with a single stitch moving forward and backward. The best way to navigate this stitch on a new machine is to consult the sewing machine manual and find out how the stitching mechanism works.
How to Sew Lock Stitch, Step by Step Instructions
If you have a mechanical or industrial sewing machine, it will not have an automatic lock stitch function. Here is how to you sew a lockstitch with a simple adjustment to the stitch length.
Method #1: Basic Lockstitch
- Start with small stitches (L 0.5 or less) and sew two to four stitches on the spot as a way of jamming the stitches together.
- Adjust the stitch length to suit the fabric (most are L2.5) and sew normally until the end.
- Lockstitch at the end of the seam.
Method #2: Lock Stitch with a Knot
Lock stitch that needs extra securing may be ‘locked' by hand after the stitching has been started. This is a time-consuming method if you are in a hurry to finish your garment, but for fine fabrics and delicate seams, this is a sure way of locking the threads and keeping the seam secure.
- Leave a tail of thread at the beginning and the end of the line of stitching.
- Pull the top end of the thread through to the wrong side of the fabric.
- Use the point of a pin to pull the loop through so there are two threads visible on the wrong side of the fabric.
- Knot these together on the wrong side of the fabric.
Advantages of a Lock Stitch
Lock stitch has the following simple advantages:
- Does not use a lot of thread.
- Stops seams from puckering.
- Looks the same on both sides of the fabric.
Best Thread for Lock Stitch
It is important to use the right type of thread for your lock stitch. Choose a good quality polyester thread that has been strengthened.
When to Use Lock Stitch
The lock stitch is particularly useful for sewing situations where the front and the back of the sewing must look the same. Topstitching for cuffs and collars is an example of when to use lockstitch. Lock stitch is also used for darts and sewing sheer fabrics.
Embroidery Lock Stitch
Lock stitch, used as a hand stitch, makes a very simple foundation for a border in an embroidery pattern. The stitch itself is a basic stab style stitch making straight parallel stitches the same distance apart. Lock stitch can be used as part of a curved border as the stitch direction makes a subtle curve across the pattern or edging of the embroidery design.
- Create a base row of straight stitches between two lines. Change color.
- Bring the new color up on the left of the first stitch.
- With the thread above the needle, insert the needle under the first stitch from right to left.
- Move to the next parallel stitch (blue). Insert the needle under the stitch making sure that this time the thread is below the needle.
- Continue in this fashion across the row.
Lock Stitch - In Conclusion
A lock stitch will prevent the ends of your seams from unraveling. It creates strength and durability while reducing bulk in delicate and fine fabrics. If you start simple with this basic stitch you will soon be locked into the joys of sewing and easily move on to other stitches and uses of your sewing machine.