Step right up, folks. It’s the embroidery horror show! Got your attention? This topic lurks under the surface but rears its ugly head in the wrong places from time to time…

bobbin on top

What is that scary situation? It happens when you see the bubbly bobbin thread on top as it peeks at the edges of letters and objects. How can we stop it, and why does it happen?

If you have ever used a black bobbin thread under a white stitch-out, you may have seen those annoying little loops of black bobbin edging your white design. If this has happened, you’ve experienced bobbin problems. Your bobbin thread should not be showing on the top of your design.

Bobbin thread showing on top of your design can be caused by a few factors, including when you stitch very narrow satin stitch or narrow tatami stitch lines and when there are tension or lint debris issues with your machine.

Bobbin Thread In Embroidery (what it’s Used for & Why)

Sewing and embroidery machines use a “lock stitch,” which twists the top and bottom thread together by turning the bobbin past the needle as it dips into the machine to create an embroidery design. The bobbin is usually plastic for home machines and metal or paper for embroidery machines.  

Bobbin thread is relatively thin, generally 60 wt (remember the higher the number, the thinner the thread), and most often sold pre-wound in white or black. It is very strong and usually not twisted like other threads; it is a single long strand called monofilament.

Why Is My Bobbin Thread Showing On Top?

There are many reasons why your bobbin thread can show on the top, but here are the top three reasons:

  • The bobbin is incorrectly seated, going the wrong way, and not correctly running through the tension spring. Refer to your manual, but a good rule of thumb is that it doubles back on itself. Here is what it usually looks like:
bobbin thread direction
  • The bobbin tension is too loose (or the top tension is too tight). This is a tricky one! There is a friendly tug of war in a sewing or embroidery machine, and the goal is for the bobbin to be a bit greedy and pull that top thread down underneath a little! Don’t try to adjust your settings without consulting your manual, and if the problem is severe, check with your dealer or repair shop.
  • Know about your machine’s tension. A simple “H test” will tell you a lot of information about what is going on under there. Many embroidery machines have this available within the machine. If not, you can create an embroidery file with Capital Hs.
h test
    • When stitched out, you will check the back of the stitched sample and gauge how far under the top thread is being pulled.
      • You should have 1/3 bobbin thread in the middle and 1/3 of each top thread on either side.
      • If they meet in the middle, the top thread is too loose or your bobbin is too tight. (It’s getting pulled together).
      • If the top thread barely shows on either side, then the top thread is too tight, or your bobbin is too loose and will eventually pull the bobbin thread up
h test back

Though the H test will not tell you exactly what is happening, it will tell you if something is happening. Every embroiderer should have this file to test and use regularly.

How Do I Stop Bobbin Thread From Showing On Top?

Here are three ways to improve your stitching and get better results:

1. Keep your bobbin case and area clean and free of lint and dust.

Although getting out that can of compressed air sounds good- leave it on the shelf! Blowing, even at lower pressures, can drive fuzzies and dirt down into your machine, and you will not be able to reach them.  

no spray bobbin

Little fuzzies can also drag the bobbin thread or force the tension flap spring open. Pay attention to your top tension in single-needle machines or your multi-needle too. Routinely check the bobbin area and thread path for debris and dust off with a soft brush. Making a dust cover for your machine will keep it clean and ready.

For the multi-needle users, make sure the tension flap on the bobbin case is clean. Slipping a business card under the flap is an easy way to remove lint and dirt. Please make sure not to bend the flap but this will help dislodge anything holding it open.

card bobbin case

For our multi-needle friends, always follow the machine manual on oiling your machine. Dry-dragging bobbins can create problems too! A word of caution regarding oiling, more is not better. Over-oiling can also leave a puddle of oil which can slow things down.

2. Slow down your machine.

Just because your machine can go 800-1000 stitches per minute does not mean that it will produce the best stitch-out. The faster the machine goes, the less “rebound time” for the thread. The top thread can then pull up your bobbin thread.

3. Use bobbin thread for your bobbin.

It is designed to be thinner, adding less bulk to your stitch-out and allowing it to glide easily. Most bobbins come pre-wound in black or white. Magnetic bobbins are also an option for multi-needle machine users; the magnetic hold on the metal bobbin case reduces the “rebound” of the bobbin and allows the thread to be evenly released.

different bobbins

Conclusion: Bobbin Thread Mistakes Can Be Easily Prevented

Of course, this scratches the surface, but if you have to have a takeaway from this session- keep your embroidery machine clean and educate yourself about how it works! The more you understand how the stitches are made and the components of your machine, the better an embroiderer you will become.

If you want to grow your embroidery skills, check out our free Machine Embroidery Beginner Series on Youtube for informative and easy-to-understand videos which will walk you through the basics of hooping, stabilizer, thread, and more!

Ohh one last thing! Want some beautiful free embroidery designs? Don’t forget to download our Free Embroidery Legacy Design Kit today 🙂