The basic steps to wind and insert a bobbin
To refill a bobbin, you wind thread onto an empty bobbin using your machine's winding mechanism, then insert the wound bobbin into the bobbin case below the needle plate. The process takes about two minutes once you know where each part is. Most machines wind bobbins the same way: you place an empty bobbin on the winding spindle, guide thread through a tension disc, press the bobbin against a rubber wheel, and step on the foot pedal or press a button until the bobbin is full. Then you remove it, thread the bobbin case, and slide it back into the machine.
The exact location of the winding spindle and the shape of your bobbin case depend on your machine model. Machines fall into two categories: those with a top-loading bobbin case (you drop the bobbin straight down from above the needle) and those with a front-loading case (you slide a metal or plastic holder out from the front). Both work the same way once the bobbin is wound — the difference is just where you insert it.
Key Takeaways
- Empty bobbins go on the winding spindle, usually on the right side of the machine near the top, and thread passes through a tension disc before the bobbin touches the rubber wheel.
- The bobbin is full when the winding mechanism stops automatically or when you reach the line marked on the bobbin; overfilling causes thread to slip during sewing.
- After winding, thread the bobbin case by sliding the thread under the tension spring and through the slot, then insert the case into the machine following your manual's diagram.
- If thread keeps breaking or loops appear on the back of fabric, the bobbin case is usually threaded wrong or the bobbin is wound too loose.
Locating the bobbin winding parts on your machine
The winding spindle is a small rod or post, usually on the right side of the machine near the top. On some machines it is horizontal (thread goes on from the side); on others it is vertical (thread goes on from above). Check your manual's diagram to find it on your specific model — the location varies widely between brands and even between models from the same brand.
Next to the spindle you will see a rubber wheel or disc, sometimes called the bobbin winder tire. This wheel does the actual turning. Between the spindle and the wheel is the tension disc for bobbin winding — a small metal or plastic piece with a slot or opening. This disc controls how tightly thread wraps onto the bobbin and is separate from the needle tension dial on the front of the machine.
Some machines have a lever or button that disengages the needle while winding; others do not. If yours has one, move it before you start winding — this prevents the needle from moving while you wind and keeps you from accidentally hitting it. Your manual will show you whether your machine has this feature and where it is.
Winding thread onto an empty bobbin
Start with an empty bobbin designed for your machine. Bobbins are not universal — a bobbin for a Janome will not fit a Singer, and plastic bobbins are not interchangeable with metal ones. If you are not sure which bobbin your machine uses, check the manual or bring your machine to a fabric store and ask them to match it.
Place the empty bobbin on the winding spindle. If the spindle is horizontal, slide the bobbin on from the side. If it is vertical, drop it on from above. The bobbin should sit flat and spin freely without wobbling. Take the thread from your spool (still on the machine's spool pin) and guide it through the tension disc for bobbin winding. The thread should sit in the slot or opening so it is under tension. Do not skip this step — thread wound without tension will be too loose and will cause loops on the back of your fabric.
Press the bobbin gently against the rubber wheel. On most machines, this is done by hand; on some, a lever holds it in place. The bobbin will now turn when the wheel turns. Step on the foot pedal or press the start button (depending on your machine type) and let the bobbin wind. Watch it as it fills — the thread should wrap evenly in layers. If it bunches to one side, stop and reposition the bobbin so it sits straight against the wheel.
Stop winding when the bobbin is full. Many machines have an automatic shutoff that stops the wheel when the bobbin reaches the right fullness. If yours does not, stop when the thread reaches the line marked on the bobbin, or when the bobbin is nearly full but not overflowing. Overfilled bobbins cause thread to slip during sewing and can jam the bobbin case. Cut the thread and remove the bobbin from the spindle.
Threading the bobbin case
The bobbin case is the small metal or plastic holder that sits below the needle plate. It has a slot for thread and a tension spring. On top-loading machines, you can see it by lifting the presser foot and looking down. On front-loading machines, you pull a small lever or button to slide the case out from the front of the machine.
Insert the wound bobbin into the case with the thread end pointing toward the tension spring. Slide the thread under the spring and through the slot in the case. The thread should sit snugly in the slot — if it is loose, it will not wind correctly and you will get loops. Pull the thread so it lies flat in the slot, then trim the end to about two inches.
On front-loading machines, slide the case back into the machine until you hear or feel it click. On top-loading machines, lower the case back down into the machine and close the needle plate cover. Some machines have a small latch or lever that holds the case in place; make sure it is closed before you start sewing.
What to do if the bobbin winds unevenly or too loose
If thread bunches on one side of the bobbin as it winds, the bobbin is not sitting straight against the rubber wheel. Stop winding, reposition the bobbin so it is centered, and start again. Uneven winding causes thread to break during sewing because some layers are tighter than others.
If the wound bobbin feels soft or squishy instead of firm, the tension disc was not engaged properly. Remove the bobbin, rethread it through the tension disc, and wind again. Thread wound too loose will slip inside the bobbin case and cause loops on the back of your fabric. You may need to wind the bobbin a second time if the first attempt was too loose.
If the bobbin winds but the wheel does not turn smoothly or makes a grinding sound, the rubber wheel may be worn or dirty. Clean it with a dry cloth. If it is cracked or flattened, it may need to be replaced — this is a repair your machine's service center can do.
Troubleshooting thread breaks and loops after refilling
If thread breaks while you are sewing after refilling the bobbin, the bobbin case is usually threaded wrong. Stop, remove the bobbin case, and rethread it. Make sure the thread sits in the slot and under the tension spring. Also check that the bobbin itself is wound firmly — if it is too loose, the thread will slip and break under the tension of sewing.
If loops appear on the back of your fabric, the bobbin tension is too loose. This usually means the bobbin case is not threaded correctly or the bobbin was wound too loosely. Rethread the case first. If loops continue, wind a new bobbin and make sure the tension disc is engaged as the bobbin fills.
If the needle thread breaks instead of the bobbin thread, the problem is usually not the bobbin — it is the needle or the upper threading. Check that the needle is inserted correctly and that the upper thread is seated in all the guides. A bent needle will also cause breaks.
Frequently Asked Questions
Can I use any bobbin in my machine?
No. Bobbins are machine-specific. Metal bobbins and plastic bobbins are not interchangeable, and bobbins from different brands usually do not fit. Check your manual or the bobbin case itself — most cases have the correct bobbin type printed on them. If you are unsure, bring your machine to a fabric store and ask them to match it.
How do I know when the bobbin is full?
Most bobbins have a line marked on them. Stop winding when the thread reaches that line. If your bobbin does not have a line, stop when it is nearly full but not overflowing — the thread should not bulge over the edge. Many modern machines have an automatic shutoff that stops winding when the bobbin is full.
What if my machine does not have a bobbin winder?
Some older or specialty machines do not have a built-in winder. You can buy a separate bobbin winder that plugs into the wall or runs on batteries. These work the same way as a built-in winder — you place the bobbin on the spindle, thread it, and let it wind. Fabric stores and online retailers sell them for $15 to $40.
Why does my bobbin keep coming loose inside the case?
The bobbin case may not be inserted all the way, or the latch may not be closed. On front-loading machines, push the case in until you hear a click. On top-loading machines, make sure the needle plate cover is closed. If the bobbin still moves, the case itself may be worn and need replacement.
Can I wind a bobbin while the presser foot is down?
No. The presser foot must be up before you wind a bobbin. When the presser foot is down, the tension discs are engaged and will not let thread pass through. Lift the presser foot first, then wind.