Sewingfilter: loops on bottom of fabric

April 12, 2005 8:42 AM

When using my sewing machine, large loops and tangles of thread are generated on the bottom side of the fabric. What am I doing wrong and what do I need to do to remedy the problem?
posted by kc0dxh to clothing, beauty, & fashion (15 comments total)

on my Singer machine, that's a clear indication of a bobbin problem. happens when i load the machine with bobbins from my mother's machine. happens on her machine when you drop the bobbin upsidedown (what a design flaw that is--right-side-up-only bobbins!). also happens when the bobbin has a stray thread that is screwing up how the thread feeds.

i usually run a test strip through the machine before sewing any time i reload the bobbin.

also, after you rip out the ruined stitches, lay the fabric flat and rub a dampened cotton swab over the needle holes to smooth them away before resewing. it helps prevent fraying when you keep sewing over the same spot.
posted by crush-onastick at 9:00 AM on April 12, 2005

It could be the tension is out of adjustment. Normally there is a knob somewhere on top of the machince to adjust the top tension. The bobbin tension is usually more difficult to adjust and you would need to look in the manual for that. Right now it sounds like the top tension is way tighter than the bottom tension. The above post about the bobbin problems could be right on as well. Eliminate that possibility first before starting on changing the tensions.
posted by juggler at 9:09 AM on April 12, 2005

this is probably a tension problem. there is a discrepancy between top and bobbin thread tension.

the looping is a too loose tension in the bobbin or too tight a tension on the top thread. in either case, and regardless of cause, the two are out of synch.

try adjusting bobbin tension according to your machine type. my machine has a screw on the bobbin case that you turn either clockwise or counterclockwise. your machine's may be different. check your handbook or find online help specific to the make of machine

after adjusting the bobbin tension sew on a piece of scrap. use a medium sized stitch. check and adjust and test until you are satisfied.

if the looping isn't severe, adjust top string tension slightly looser.

there are other causes for this problem, but they are more unusual and should be considered only if the common remedies don't answer.
posted by subatomiczoo at 9:11 AM on April 12, 2005

Is it the top thread or the bottom thread?

If it's the top thread, it's not threaded correctly through the tensioners and needle (or something is broken, but user error is more likely). Make sure that you've threaded it correctly, and that all the tensioners are working properly (I usually spin them all the way in each direction, then re-set them). Double check for linty bits in the tensioners.

Also, if the looping is at the beginning of your seam, try holding the threads taut as you start sewing....sewing machines are designed to stitch properly when there's a certain amount of tension on the thread, and if the threads loose, you'll get tangles.

If it's the bottom thread, the bobbin isn't wound or loaded correctly, or it's the wrong bobbin. Don't mess with the bobbin tension unless you have to. If the machine had been working before and is not now, the problem is most likely not in the bobbin tension. The adjustment range is really tiny, and it's easy to mess it up. (I sew everything from sheers to linen to polar fleece without resetting the bobbin tension.)
posted by jlkr at 9:20 AM on April 12, 2005

If it still loops after you redo the bobbin, you might also check the parts around the bobbin. Our machine was bunching up for my wife and I cleaned up all the fuzz that had collected around the bobbin and made sure everything was working smoothly (a drop of oil, and I mean a drop, worked wonders) and no more problems.
posted by rodz at 10:50 AM on April 12, 2005

It's clearly a tension issue, and the previous answers are right-on for troubleshooting that. But if you're a new or infrequent sewer and this only happens occasionally, it's possible that you're sometimes simply forgetting to lower the presser foot before you start sewing, which keeps the top tension mechanisms from engaging. This can easily happen when you're sewing thru thick layers and can't see any gap between the fabrics and the bottom of the foot whether the foot is up or down.
posted by dpcoffin at 12:26 PM on April 12, 2005

I second the admonishment not to fool around with your bobbin tension. Everything on the topside is fair game, but stay away from adjusting the bobbin unless you feel like paying the nice man at the sewing machine repair shop to fix it after you've dorked it up.

My Kenmore does something similar which I attribute to a design flaw. If the bobbin rises ever so slightly in the bobbin cage, the bobbin thread ends up in the ugliest of rat's nests on the underside of the workpiece. The only method I've found for fixing it is to be diligent about ensuring the bobbin is correctly seated.

(I find it fascinating that half the answers on this thread have come from guys. Not to derail, but what are you guys sewing? I was a kitemaker in former life.)
posted by friezer at 1:10 PM on April 12, 2005

friezer: are you sure? i see 7 responses, 4 with neither a real name nor gender in profile, 2 with male names in the profile, and one with a female name in the profile, which doesn't add up to "half the answers coming from guys" (especially because i know that at least one of those no real names-no gender specified is not a guy)
posted by crush-onastick at 1:18 PM on April 12, 2005

Well, I'm a guy...and I've never found bobbin-adjusting that daunting (not implying any connection between these two facts!) (I sew shirts and pants mostly, btw...and write about sewing professionally...)

To adjust a bobbin case, my I-am-not-a-machine-technician rule of thumb is to never make more than 1/4-turns of the bobbin screw between tests (see below), and to never work on the bobbin unless it's over a tray of some kind that will keep the screw from disapppearing into the carpet if it falls out. For my purposes, a correctly tensioned bobbin case will dangle securely from the thread of a full bobbin inside, but will slide down an inch or so along the thread if you bounce the weight of the case against the thread a little bit. Get that right, then do the fine adjusting up top, and it always works for me.
posted by dpcoffin at 1:41 PM on April 12, 2005

Wow! What a sea of answers. Allow me to start by saying that I am a guy and I'm new at this (sewing and MeFi). My wife is starting to sew and, well, it's a machine. I couldn't keep my hands off.

To clarify some, the machine is a singer, is new, and has less than 5 hours running time on it. I have managed to get good stitches on light fabric, but when I was sewing a patch it caused these loops and tangles.

The bobbin I'm using came with the machine and I've never adjusted the bobbin tension. The manual said nothing about this, but then the manual only has 8 pages in English.

How do I tell if it is the top thread or bobbin thread causing the loops? Is there a trick to this?
posted by kc0dxh at 2:38 PM on April 12, 2005

I can't believe David Coffin is here giving advice in a sewing thread. Eeek! Now I feel all like an amateur who shouldn't be saying anything.

I think what you're describing is called 'birdnesting' and is caused by missing the tension plate, or the take-up arm while you're threading. Careful rethreading usually solves it for me. The term, though, might help you with googling more specific instructions if you're not able to solve with the advice given here.

Also, based on your update, if the machine is new, take it back to the store where you bought it, and ask them, assuming you bought it from a store. Generally sewing machine stores are great on service and learning.

In terms of figuring out which it is, the top thread/rethreading is probably the easier to fix, so I'd start by experimenting with that to see if you can resolve the issue. I'd only move to adjusting the bobbin if rethreading it doesn't work.
posted by jacquilynne at 2:44 PM on April 12, 2005

To figure out whether it's a top thread or a bottom thread that's looping, thread the needle with a different color thread. (and, of course, rethreading may solve the problem.)

However, if it worked on a lighter fabric, you may need to use a heavier needle and tighten the needle tension. Heavier/thicker fabrics generally need a thicker needle, and often (usually, IME) require that the needle tension be higher.

(squeee! David Coffin. I'm not worthy, I'm not worthy!)
posted by jlkr at 5:13 PM on April 12, 2005

Well, I'm not nec. worthy, either, jlkr, but it'd be a shame if that stopped us, right? Lots of better advice above than I came up with...but the problem happening with a brand-new sewer sewing a patch on a brand-new machine does support the idea that maybe just then kc0dxh couldn't tell if the presser foot was lowered. In any event, I think it's most likely by far that the top tension not engaging is the problem, if the stitches look fine from the top. The top thread has to loop around the bobbin to make the stitch and the top tension mechanism has to engage so the take-up arm can pull these loops back up again; "birdnesting" happens when they don't get pulled back.

And so, jacquilynne: Where else should I (or anyone else) be giving advice if not here:-)? MeFi forever! It's a lot more interesting than most sewing forums; people ask the most amazing things and get the most marvelous replies...and nobody ever has a snit about being OT....but don't quote me...pls!
posted by dpcoffin at 6:54 PM on April 12, 2005

Oh, I'm more than pleased that you're giving advice here. I'm just very slightly awed! One of the cool things about metafilter is how many experts there are on various things here, I've just never seen an answer from an expert that I recognized who was an expert on something I'm interested in.
posted by jacquilynne at 7:02 PM on April 12, 2005

I'm a guy, I sew a bit. I learned in the Navy as a parachute rigger. I read the thread but y'all answered 'tension', which was my first idea.
posted by Goofyy at 12:20 AM on April 13, 2005