Bobbin winds unevenly and very loose - Singer 3116 Simple

Make sure the bobbin is seated all the way on the winding pin. There may be an adjustment for it--a technician can probably fix it for you. However, you can also try lifting the thread with a pencil tip just before it winds onto the bobbin. Some of my machines wind the thread unevenly (more on the bottom than the top of the bobbin) and I balance it out by lifting it when winding.

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I always use my finger to guide the thread as the bobbin is winding,the bobbin shouldn't be moving around in the metalcase probably needs tightened.

Check to make sure the thread path from the spool to the bobbin is correct. The thread should make a loop around a little post that is actually a tensioner that helps the thread wind smoothly onto the bobbin. If something is wrong with that tensioner or the thread is not following the correct thread path, it could cause the thread to not wind smoothly. It appears that your machine has two locations where the spool can be placed to wind the bobbin. You might try using the other option, if one doesn't seem to be working.

Also, you might try slowing the machine down during the thread winding process. It it goes too fast the spool begins bouncing and pulls the thread akilter. Also, some threads will stretch if the winding is too fast causing the thread to "shrink" when sewing your garment and creating puckers.

FWIW, I found that a "SideWinder" stand-alone bobbin winder is a handy gadget. It is available for ~$30 from JoAnn's Fabrics, Amazon, etc and is battery or electric compatible. It saves wear and tear on a machine and can wind multiple bobbins one right after another. Just be sure to verify that your bobbins will work on the SideWinder as some Singer bobbins will not.

You need to ensure that the thread is going from the thread spool at the back of the machine, through the eyelet, then around the silver tension disc on top of the machine, then to the bobbin when you are winding it. Also, pull the thread tail up through the hole in your bobbin to start and hold the tail so the thread starts to fill smoothly and doesn't loosen.

I've marked the disc in red on this image

Please read my Tip on bobbin winding; its really important to get a good wind and you can add more tension yourself by applying gentle pressure to your thread spool on the back pin as you wind off it.
Link is http://www.fixya.com/support/r10598580-winding_bobbin_correctly

The stopping when full is possibly because your bobbin is winding unevenly but I never run it until it stops itself anyway, and do the winding at 3/4 speed, not flat out. You want a really smoothly tensioned even wind onto the bobbin so your thread comes off the bobbin when stitching with even tension, not stretched, then loose.

Hope this helps you with your problem.

Sounds more like the way the bobbin has been wound, is it loose and uneven or tight and smooth. Is it properly into the tension spring? being loose doesn't sound right, a thread under correct bobbin tension is usually pretty firm.

Is it loaded into the bobbin holder the right way ?

Also check the bobbin itself hasn't been damaged in some way, not worn/bent. It needs to turn smoothly in the bobbin holder so if one edge has been bent a little this will cause problems.

When winding bobbins, you must have tension on the thread so it winds smoothly with consistent tension on the thread. Most machines have a little tension disc on top or the thread goes through the regular tensioner in order to achieve this. But I always wind bobbins at about 3/4 speed and also add a little extra tension by holding my scissors handle on top of the thread spool so it doesnt bounce around. Also start winding with a little tail pulled through a hole on top of the bobbin and wind until this starting end is covered, then stop and snip off the tail. Then continue winding and watch the thread, giving it a nudge so that it fills evenly across the bobbin, not just all in the middle.

Think of it like the garden hose reel; if you wind it really fast the hose all goes into the middle of the reel, then jams up and you can't get the whole hose onto it. Same thing, wind smoothly and evenly across the whole depth of the bobbin so that the thread is smooth and even. Then when the thread feeds off it will be smooth evenly tensioned and should stitch out evenly.

There is some good trouble shooting information on this page too which might help you to work out what is causing this thread breakage.
http://sewing.about.com/od/sewingmachineindex/a/mtroubleshot.htm

you can dowload a manual from the singer website http://www.singerco.com/accessories/manuals.html

If the bottom stitching is uneven, its mostly the top thread not under tension correctly so check the tension dial and the threading up from the thread spool to the needle.

Also, review how you wind a bobbin, you want a nice smooth wind, not twisting or uneven build across the bobbin. The manual for this machine is pretty brief on this but bobbin winding is crucial to getting a good even flow from the bobbin when stitching seams. You want to wind thread smoothly onto the bobbin, across the full width of it, not just mainly in the middle. Give the thread a nudge with your finger tip to fill top and bottom as it winds.

Also, ensure the thread goes through the bobbin tension disc on top of the machine, and even then, use your scissors handle to put some downward gentle pressure onto the thread spool you are winding off so it doesn't jump or bounce as you wind. Wind the bobbin to 3/4 full, then stop.

And lastly, load the bobbin correctly following the manual directions, make sure it is turning the right way in the bobbin case. Also look at page 16, it shows the "dangle" test where you can check the tension on the bobbin case is right, you should be able to dangle the bobbin by the thread tail and it should "stay" but you should be able to pull on it to release thread too. Adjust the little tension screw in minute increments to get this right. Bobbin case tension springs can fail or break too, so check this out.

Hope this helps you; it is my experience that 90% of machine issues are caused by blunt or wrong sized needles, wrong threading, no tension or incorrect tension or lack of maintenance.

This could be one of the following:

• wrong bobbin for the machine
• bobbin loaded the wrong way - must rotate anticlockwise when you pull the thread
• thread not into the tension spring/device on the bobbin holder correctly
• bobbin wound badly, uneven tension, loose or uneven across the bobbin
• poor quality or old dry brittle thread could cause the breaking (but the loops is definitely tension issues).

This is a top loading bobbin machine machine and you can download a manual from
http://www.singerco.com/accessories/manuals.html

Here is the threading diagram from the manual.

It is important to click the thread down into the tension spring on all top loading bobbin machines and then pull gently on the thread to check that it is under tension, you should feel firm resistance when you pull the thread. If not, then take it out, and try again.

Other thing to look at is how the bobbin is wound. It is necessary to wind a bobbin smoothly and with some tension on the spool as the thread comes off it. Best analogy is the garden hose reel. If you wind it up and don't control where the hose goes onto the reel it will all lump up in the middle, and you won't get all the hose onto it. And then when you go to pull the hose out, it will jam and be difficult to pull. Same with bobbin thread. You want a nice neat even fill across the whole width of the bobbin, not just the middle. To achieve this make sure you use the bobbin winder tension disc when winding. Also use the spool cap on top of the thread spool to stop it from bouncing around as it unwinds - the thread will then wind off around the spool cap and this keeps it running smoothly and not twisting and jerking. If you don't have a spool cap then put the curved handle of a pair of scissors on top of the thread spool to tension it while you wind the bobbin. Also watch the bobbin as it winds, give the thread a nudge with your finger to control the fill onto the bobbin so it winds top, bottom and middle of the bobbin evenly.

I would suggest the following:
clean out the race following the manual directions to remove the bobbin holder, clean in this area, replace it. Wind a fresh bobbin and then load it into the machine, following the manual instructions carefully. Also thread the top of the machine following the manual, put in a new sharp needle from the pack, turn the top tension dial to a medium number (often 5 if dial goes from zero to 10).

Now test sew again. Look at the seam, if you have loops on the bottom of the fabric, underside, then the top thread tension is too loose or not in the top tension discs fully. Generally you should not need to adjust the tension on the bobbin thread for these machines.

You need to keep tension on the thread spool as you wind the bobbin to avoid this from happening. Also, is there a little tension device to take the thread around between the spool and the bobbin winder? Some machines have a little silver button tensioner purely for bobbin winding to keep the thread flowing smoothly.

But I always do the following anyway just to ensure a smooth bobbin. Take the thread from your spool, through the eyelet or tensioner, then back to the bobbin and put the tail end up through a hole in the top of the bobbin. Now put the bobbin onto the winder and click it against the stop. Place the curved handle of a pair of scissors onto the top of the thread spool and apply some gentle pressure to stop the spool from bouncing and jumping while winding off. Keep doing this through the winding process.

Start the bobbin winding mechanisim, its a button on my Janome 6500, yours might be a little different. HOLD the thread tail until you've got coverage over the whole bobbin area catching the starting point. Stop, trim the thread tail off top of the bobbin with scissors, then restart winding again. Watch as the thread winds and give it a nudge with your finger tip to the top or bottom so the bobbin winds evenly across the whole spool's width.

Best analogy here is when you wind the garden hose onto the reel, if it goes on all over the place you never get the whole length on neatly, but if you wind it on neatly in an even tight coil across the spool, then back again, then repeat, you get a tidy hose. But just wind madly, it all builds up in the middle, you can't get it all onto the reel, and it won't pull out nicely next time you need it. Same thing with your SM thread.

Polyester and silky embroidery threads will be worse too as they are silky, so if the thread hasn't been wound on smoothly and under tension, then it will "collapse" with gravity, then when you use the bobbin, the thread is going to be caught on itself, will feed unevenly and be stretched, then loose, giving you less than perfect stitch tension.

My other bobbin tip is store the bobbins in a plastic bobbin tray so they are lying on their edges and under a cover. Keeps them neater and they are less likely to unwind stray threads around your sewing cabinet if you store them on the spool pins build onto the cabinet door - and it keeps the thread dust free. But I do not keep thread on bobbins for long, prefer to wind a fresh one off a new spool when I start a project and can usually complete a garment with a 3/4 filled bobbin, use the remaining few metres for handsewing, then junk the rest. Then I put the thread spool that is left back into a sealed takeway container to keep it away from UV, dust and moisture.

I hope this assists you with your machine and certainly if this doesn't resolve the bobbin issues, then I'd suggest you visit your dealer and ask them to demonstrate the technique on your machine to see if there is a technical issue with it.

Double check you are threading correctly for bobbin winding. It should wind neatly till it can't turn, and then you stop winding; at least this is how it works on the 8000. Perhaps there is some thread blocking the thread guide for the bobbin winding

It should not affect the winding, the reason the needle is still going up and down is because the oil has gone dry on the shaft and unless you can get to the shaft where the balance wheel is then it would be wise to take the machine in for a service, loose stitching on the bottom is a tension problem, make sure the top tension is set about 4 or 5