The thread winder is winding the thread too loose on the bobbin. How do I adjust that.

Sounds like your stitch is bad? If so then check you tension on the upper and also on the bobbin. Typically there is an adjust for the upper tension and for the bobbin on the bobbin case. There are many you tube videos on how to adjust tension for both to get a great stitch. If you are talking about the bobbin thread only then you may have to clean the bobbin area where it self winds or if it is an older machine with outside winder check to make sure it is winding correctly ie back and forth on the bobbin which can be adjusted with tension on the winder itself.

1. Turn the power on the machine.
2. Open the bobbin winder cover at the top on the right side of the sewing machine.
3. Swing up the bobbin thread spool pin. Move the bobbin thread spool pin up as far as possible.

1-Bobbin thread spool pin
4. Place the bobbin on the bobbin winder shaft so that the spring on the shaft fits into the notch in the bobbin.

1-Notch
2-Bobbin winder shaft spring
5. Slide the bobbin winder shaft to the right.

NOTE: If the correct size bobbin is not used at this time; when the bobbin winder is engaged; the bobbin winder will make a usual noise and not wind the bobbin correctly.
6. Place the spool of thread for the bobbin onto the bobbin thread spool pin.
7. Slide the spool cap onto the bobbin thread spool pin.
NOTE: If using thread that winds off quickly, such as nylon or metallic thread, place the spool net over the spool before placing the spool of thread onto the spool pin.
8. Pull out some thread, and then thread the thread guide for the bobbin winding. Hold the thread with both hands, and then securely pass the thread as far as possible into the two slits in the thread guide.

1-Thread guide for bobbin winding
2-Two slits
9. While using your left hand to hold the end of the thread that wraps around the thread guide for bobbin winding, use your right hand to wind the free end of the thread clockwise around the bobbin five or six times.

10. Pull the thread to the right and pass it through the slit in the bobbin winder seat.

Check that the bobbin is seated all the way down on the bobbin winder spool. However, the bobbin winder most likely needs a slight adjustment. I have several machines that tend to wind the thread either high or low on the bobbins so I just use a stiletto or pencil to raise and lower the thread as it winds. It helps to wind the bobbin at a slower speed--reduces stretch on the thread and allows you the ability to manually guide the thread onto the bobbin.

If you'd like to save wear & tear on your machine and be able to wind bobbins without unthreading the machine, look for a stand-alone bobbin winder (one brand is called "Sidewinder"). They cost around $30 and can be found online or at most fabric stores like JoAnn's. Just be sure to verify your bobbins will work on the winder--some Singer and other brand bobbins will not work.

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Hai, Please change the new bobbin winder. Because bobbin winder and winding is very important.

Needle breaks
1.the needle is damaged
2.the needle is not correctly inserted
3.wrong size needle for the fabric
4.the wrong foot is attached
5.the needle clamp screw is loose
6. Top tension is too tight--loosen off one letter or number till the stitch
looks normal
7.make sure that every thread guide is used when winding the
bobbin,, so that the bobbin will wind tightly, if this doesn't help,,
then it's possible that the bobbin winder needs adjustment,, it needs
to be taken to a sewing machine shop

if the bobbin winder spindle shaft is loose then the machine needs to be fixed because thats not normal

BRAND new Janome 1420qdc. New needle, doesn’t need oil. Will NOT wind a bobbin. Used almost an entire spook of thread doing this. At my wits end. HELP!

If you are finding that the bobbin is winding with more thread towards one edge of the bobbin than the other, the bobbin winder motor needs to be adjusted so that the angle of the winder shaft is properly aligned with the tension disc next to the head cover. Unfortunately, unlike many of the other models, you have to remove the covers on the Activa range to get at the adjuster. There is a spring-tensioned screw just to the left of the bobbin winder motor that adjusts the angle of the motor and therefore how it loads the bobbin. If the winder is loading the bobbin with most of the thread towards the bottom edge, the screw should be turned clockwise and if most towards the top, it should be turned anticlockise. Make adjustments until the thread is winding evenly or, at least, towards the centre of the bobbin.

If you are finding that your bobbin is being loaded somewhat randomly, make sure you are using the vertical spool holder to hold the spool and that you've got a foam pad under the thread spool. Route the thread through the thread guide before winding around the tension disc in the correct direction (see the arrow on the case) and ensure that the spool and thread do not vibrate unduly when the bobbin is being wound. If you let the spool vibrate whilst the bobbin is loading, it may result in varying tension on the thread and uneven winding onto the bobbin.

I have that machine. Either the bobbin isn't all the way down on the bobbin winder or the thread isn't under the top part of the bobbin winder guide. These must be plastic bobbins.

hi!there similar bobbins winder in any brand of sewing machine uses mostly in domestic particularly in industrial manufacturing in this fig.check it out if similar to your bobbins any how itmay be helpfull onethe bobbins winder that was a thread and shoul be clockwise rotation when coming out to bobbins case,if you to wound the thread on your bobbins winder, pull threads on spool then wind this in several times 4 to 6 rotation clockwise loop thread on top machine there is bobbins winder disc for tension put winder bobbins on shaft winder near hand wheel push the latch against bobbins winder to fit thead run machine to wind the thread.After hread wound in bobbins winder cut thread and insert winder to bobbin case as shown.
insert bobbins to shuttle hook case under needle foot holder

lift the cover plate you can see under this is the shuttle hookafter set up was made on bobbins thread,set also the upper loop thead beginning at top of machine start on spool, pull thread and loop to upper disc tension then to the slot portion as in figure

insert on lever dial goes to the needle adjust tension to #8 range to #12 for cotton fabrics two layer sewing.