The bobbin goes in the bobbin case, which sits under the needle plate

The bobbin is the small spool that holds the lower thread in your Singer machine. It sits inside a removable metal or plastic case called the bobbin case, which lives directly under the needle plate (the flat metal plate the fabric rests on). To thread your machine properly, you need to wind thread onto an empty bobbin, insert that bobbin into the case, and close the case back into the machine. If your bobbin is already wound, you can skip the winding step and go straight to insertion.

Most Singer machines use one of two bobbin styles: the metal case style (found on older and mechanical machines) or the drop-in style (found on newer computerized models). The steps differ slightly between them, but the principle is the same—the bobbin sits in the case, the case holds it steady, and the thread feeds through a tension spring as the needle moves.

Key Takeaways

  • The bobbin case sits directly under the needle plate and must be removed to insert or replace the bobbin.
  • Wind thread onto the bobbin using your machine's winding mechanism before you insert it into the case.
  • Thread the bobbin through the tension spring in the case so the thread feeds smoothly as you sew.
  • Close the bobbin case fully and slide it back under the needle plate until it clicks into place.
  • If your machine is a drop-in style, the bobbin sits directly in a round opening with no separate case to remove.

Winding the bobbin before you insert it

Before the bobbin can go into the case, it needs thread wound onto it. Look for the bobbin winder on the right side of your machine (on most Singer models). It is a small spindle with a rubber wheel or tire. Place an empty bobbin onto this spindle and push it to the right until it clicks—this engages the winder and disengages the needle.

Hold the thread from your upper spool and wrap it around the bobbin two or three times by hand to anchor it. Then press the foot pedal or press start (depending on your machine type). The bobbin will spin and wind thread onto itself. When the bobbin is full, it will stop automatically, or you will hear a change in sound. Remove the bobbin, trim the thread, and set it aside.

If you are using a pre-wound bobbin from the store, skip this step and move straight to removing the bobbin case.

Removing the bobbin case on metal-case machines

On older Singer machines and many mechanical models, the bobbin case is a removable metal or plastic shell. Raise the presser foot (the hinged arm that holds fabric down) and raise the needle to its highest point by turning the handwheel toward you. This prevents the needle from catching the case as you remove it.

Look directly under the needle plate. You will see a small latch or lever on the left side of the bobbin case. Pull this latch toward you or lift it upward—the exact motion depends on your model, but it should release easily. The entire case will slide out toward you. Set it on a clean surface where you can see the tension spring inside.

Threading the bobbin through the tension spring

Inside the bobbin case, you will see a thin metal or plastic spring. This is the tension spring, and it controls how tightly the lower thread is held. The bobbin thread must pass through this spring for the machine to work correctly.

Hold the bobbin with the thread coming off the top. Slide the thread under the tension spring from left to right (or the direction your machine's manual shows—check if you are unsure). The thread should sit snugly in the groove of the spring. Pull the thread gently to make sure it is seated properly. Leave about 4 to 6 inches of thread hanging loose—you will need this to tie off when you start sewing.

If the thread is not threaded through the spring, your stitches will be loose and uneven, and the machine may skip stitches entirely.

Inserting the bobbin into the case

Now place the wound bobbin into the case. The bobbin sits in a round or oval recess at the bottom of the case. The thread should still be hanging loose. Lower the bobbin gently into the case so it sits flat and does not tilt. The thread will naturally feed through the tension spring as the bobbin settles.

Some machines have a small hook or guide that the thread wraps around before entering the tension spring. If your case has this, guide the thread through it first. Check your machine's manual if you are unsure of the exact path.

Reinserting the bobbin case under the needle plate

Hold the bobbin case by its latch and align it with the slot under the needle plate. The slot runs left to right, and the case should slide in smoothly. Push the case in until you hear or feel a click—this means the latch has caught and the case is locked in place. Do not force it; if it does not slide easily, check that the needle is still at its highest point and that the case is aligned correctly.

Once the case is locked, tug gently on the bobbin thread to make sure it does not pull the case out. The case should stay put. You are now ready to thread the upper part of the machine and begin sewing.

Drop-in bobbin machines (newer Singer models)

Some newer Singer machines, especially computerized models, use a drop-in bobbin system. These machines have no removable case. Instead, the bobbin sits directly in a round opening in the machine bed, and the case is built in.

To insert a bobbin in a drop-in machine, raise the presser foot and needle to the highest point. Open the round cover plate (usually by pressing a button or lifting a hinged door). Drop the wound bobbin straight down into the opening so it sits flat. The thread should feed through a built-in tension spring automatically. Close the cover plate until it clicks. The process is faster than the metal-case style, but the threading principle is identical.

Frequently Asked Questions

What happens if I thread the bobbin backwards through the tension spring?

Your stitches will be loose and uneven, and you may see loops of thread on the underside of your fabric. If this happens, remove the bobbin case, rethread the bobbin through the spring in the correct direction, and reinsert the case. Always check that the thread sits snugly in the spring groove.

Can I use a bobbin from a different brand in my Singer machine?

Most universal bobbins work in most Singer machines, but metal bobbins and plastic bobbins are not interchangeable within the same machine. Check your manual or the bobbin itself for the correct type. Using the wrong bobbin can cause tension problems or damage the case.

My bobbin case is stuck and won't slide out. What should I do?

Raise the needle to its highest point and try again—a lowered needle can catch the case. If it is still stuck, do not force it. Check that you are pulling the latch in the correct direction (your manual will show this). If the case is truly jammed, stop and consult your manual or contact a Singer service center rather than risk breaking the latch.

How do I know if my bobbin is wound tightly enough?

A properly wound bobbin should feel firm and smooth when you roll it between your fingers. If it is lumpy, loose, or has gaps, rewind it. A loosely wound bobbin can cause uneven tension and skipped stitches. Most machines will stop winding automatically when the bobbin is full, so you should not have to guess.

Do I need to rethread the bobbin every time I change fabric colors?

No. You only need to remove and rewind the bobbin if you want to change the bobbin thread color. If you are only changing the upper thread color, straightforward rethread the upper part of the machine and leave the bobbin alone.