Why Sewing Machine Thread Keeps Breaking

Why Sewing Machine Thread Keeps Breaking

One of the most frequently asked questions by sewing enthusiasts: why does a sewing machine tear the thread while working? It is important to note that such a malfunction occurs on both manual and electric sewing machines, and the repair methods will be the same. This problem can have several causes, including:

  • poor quality yarn;
  • improper installation of the needle;
  • voltage regulator failure.

Why Sewing Machine Thread Keeps Breaking

Poor quality thread

A common cause of a problem, when the sewing machine begins to break the upper thread, maybe excessive regulator tension or poor quality thread if constantly twisted in the regulator. Replace the poor quality wire that will not have visible defects in the form of small nodules and other damage, and the problem will stop bothering you.

When the upper thread is too tight, the machine tears it or pulls it into the slot in the shuttle. Adjust the tension force and you can use the control nut on the regulator.

Incorrect installation of the needle

The correct placement of the needle suggests that its long chute is directed towards the thread guide. When doing so, always pay attention to the correct thread thickness and needle size. The thread should pass through the needle freely and not form small clumps. If this happens, use a needle with a large ear diameter.

Too sharp a hole in the needle can cause the thread to break. Pay attention to the sharpness of the eye of the needle, and if the problem is there, sharpen the edges with a file or emery cloth.

Voltage regulator failure

If your sewing machine has been repaired recently, maybe tapered spring During the repair process, it was not collected properly, which is why the thread broke. To solve this issue, it is important to rebuild the voltage regulator. For that:

  • remove the clamping nut;
  • scroll the spring one full turn clockwise;
  • Install the nut in its original position.

it's important to pay attention to the position of the spring. It should be positioned so that its wide end is located deep in the body of the sewing machine. If this condition is not fulfilled, the spring bar will not be able to rotate freely around its axis and it will be impossible to adjust the thread tension.

If the spring does not roll and jams when rotating, straighten the top tab of the tapered spring so that the top thread moves freely.

Other reasons

Sewing Machine Thread Keeps Breaking

The following reasons can trigger such a malfunction.

  1. The shuttle poorly filled. Make sure the car shuttle is filled correctly. Otherwise, the lower thread will be fed in the opposite direction, which will cause deceleration and, consequently, breakage of the lower thread.
  2. Poor lubrication. Simply lubricating the workpieces will help the machine not to tear the sewing threads.
  3. Also, a strong grip on the lower legs can affect the quality and speed of your stitching. On some models, three modes correspond to the type of fabric used by the seamstress: heavy fabric, light fabric, and embroidery mode, you must choose the one that best suits the material used.
  4. Notches. Because to prolonged use, many notches appear on the surface of the sewing machine. Most often, this damage occurs at the edges of the needle plate. Don't worry you can solve the problem with the  polishing surface.

If you cannot solve the problem yourself, contact the master. The reason may be deeper and you want to replace some defective parts.

Read more:

How Can I Tell How Old My Singer Sewing Machine Is

How Does a Sewing Machine Work Step by Step

What Is the Best Handheld Sewing Machine


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