Open thread, also known as "open seam", is the kind of stitch that is still visible outside after sewing. It's not just about looking good, it's also about making the seams stronger. Like the double stitches on jeans, the thick threads on the bag, and the decorative threads on the sofa, they are all open seams.
If you use an industrial sewing machine, the top-stitching is fast and neat, and the efficiency is particularly high! Today I will teach you step by step how to use an industrial machine to sew open thread straight and beautifully.
1. What is open seam? What's the use?
Surface seam is to sew a clear thread on the front of the fabric, commonly used in:
·The seams of jeans and cargo pants
·The edges of backpacks, handbags
·Decorative edges of sofa covers, curtains, cushions
It has two benefits:
·Stronger: One more thread, the seam is not easy to open.
·Better-looking: The lines are neat and look professional and textured.
2. Choose the right machine to get twice the result with half the effort
Not all industrial machines are suitable for open stitching, it depends on what you are going to do. These are recommended:
a. Commercial Heavy Duty Sewing Machine
Suitable for sewing: denim, canvas, leather, thick cotton
Characteristics: Strong strength, the needle is pierced thoroughly, the thread is tightly pulled, and the sewing is particularly firm
b. 2 Needle Industrial Sewing Machine
It can sew two parallel threads at the same time, which is especially suitable for decorative open threads. For example, the double threads on both sides of jeans are sewn with a double-needle machine
Clean lines and double efficiency
c.Fully Automatic Industrial Sewing Machine
With automatic thread trimming, automatic positioning, and program setting functions. It is suitable for mass production, saving labor and making fewer errors.
·Tip: If you are a small factory or do customized packages and tooling, a double-needle machine or a heavy-duty single-needle machine is sufficient.
3. Before starting construction, adjust the machine first
The machine is selected, and it must be adjusted before it can start sewing. Don't rush to put on the cloth, do these steps first:
a. Thread the thread correctly
·Be sure to thread the thread step by step according to the instructions, and do not jump steps.
·Open seams are often used medium or thick threads (such as polyester thread, nylon thread), which are wear-resistant and strong.
b. Replace with a suitable needle
·Ordinary thick cloth: with pointed needles (such as 16#, 18#)
·Leather, artificial leather: Use a special needle for leather (the tip of the needle is like a knife edge, which can cut through the leather)
·The needle is too thin and will break, and the needle is too thick will damage the cloth, so it must be paired!
c. Adjust the length of the stitches
·Open seams generally have longer stitches to look more obvious.
·Recommendation: 3~4 mm per needle (there is an adjustment button on the machine, just adjust it to 3~4)
d. Adjust the tightness (tension) of the thread
·The thread is too tight: the cloth will wrinkle and the thread will break easily
·The thread is too loose: the coil will come out of the back, which is ugly and not solid
·Correct method: first take a piece of scrap material and try to sew a few stitches to see if the stitches are flat. If you're not satisfied, fine-tune until the front and back are neat.
4.The fabric should also be prepared
The machine is adjusted, and the fabric must be processed, otherwise no matter how good the machine is, it will be in vain.
a. The cloth should be neat
Cut according to the drawing, leaving enough seams (generally leave 1~1.5 cm)
b. The seams should be ironed
Iron the seam to be sewn with an iron first, either flat or upside down.
iron it flat and then sew, the thread will be straight and will not be crooked.
c. Draw lines and position
Use a powder, a pen or pin to mark the location of the thread you want to sew on the fabric.
Especially straight lines, draw a line as a "track", and sew it quickly and straight.
5. Formally sew open stitches, remember these tips
a. The beginning and end should be reinforced
When you sew to the end or at the beginning, press the "reverse needle key" (or manually reverse it) and sew a few stitches back and forth.
This way the thread will not come loose and unravel.
b. Sew straight lines: with auxiliary tools
Use the guide strip or tape that comes with the machine as an edge line.
You can also use a metal ruler to lean on the presser foot and push it to ensure that the line is straight and even.
c. Sew curves and corners: Slow down
When you get to the bend, slow down and gently take the cloth with your hands to turn. Don't dead-lift, otherwise the thread will be crooked and the needle will break.
d. Do you need to sew multiple threads? Keep the spacing consistent
For example, two parallel open threads should be sewn with an interval of 1 cm. You can measure it with a sewing gauge or ruler, and sew it again every time it is aligned to ensure uniformity.
6. Machine maintenance, do not be lazy
Industrial machines are used a lot, and they must be well maintained, otherwise they are easy to break and not sew.
Daily maintenance tips:
·Every day after work, use a small brush or air gun to clean the threads and dust in the nose
·Regularly lubricate according to the instructions to reduce wear
Check the needle and bobbin frequently and replace them in time if they are worn
·Ask a professional master to overhaul once a year to ensure that the machine is in the best condition
7. To summarize: remember in one sentence
The open thread should be sewn well, the machine should be selected correctly, the needle and thread should be matched well, the cloth should be ironed flat, the thread should be drawn accurately, and the sewing should be slow and steady.
As long as you follow the steps, practice a few more times, and sew open threads with an industrial sewing machine, it is really fast and beautiful, and the products you make will immediately look "high-end"!
Want to buy an industrial sewing machine? We'll help you choose!
We are an industrial sewing machine supplier, offering:
·Heavy-duty single-needle machine
·Double needle open thread machine
·Fully automatic sewing machine
Whether you are making denim, bags, sofas, or opening a small factory, we can recommend the most suitable and cost-effective machine according to your needs.
Feel free to contact us!
Our technicians will help you select, teach you the operation, and solve after-sales problems one-on-one, so that you can buy with confidence and use it smoothly!