The loosest thread – Those pesky thread nests

Some of the most common sewing machine issues I hear are:

  • “The bobbin thread is bunching up around the bobbin”,
  • “I have loops under the fabric”,
  • “It looks great on the top but the bottom looks awful!”,
  • “No matter how high I turn the tension on my bobbin, I still get a mess on the bottom side of the fabric!”,
  • “I keep lowering the upper tension but I still get loops underneath!”
  • “It’s the tension”
  • or something similar.

Something like this:

Top side of the fabric. Doesn’t look too bad.

Well that doesn’t look so bad, right? Until we turn it over…

Bottom of the fabric. This is the beginnings of a thread nest. About all that the 411G wanted to commit to today.

Ugh. ( With certain machines this is often worse – full on nests.  I couldn’t for the life of me make this 411G make the huge nests that were my constant companion with my first sewing machine.  See the end of the post for how far I went to get nests for you.)

In fact, sometimes you’ll even get extra thread wrapped up around the bobbin case and hook (Note the position of the needle.  With it all the way up, there shouldn’t be anything other than the bobbin thread showing in the bobbin area):

Bobbin thread plus friends?

I’ve talked about this before but I think it sometimes gets lost in the longer posts so I’m making it its own post and expanding on it some today because I’ve had a LOT of these comments/questions lately.

Often when I tell people this is more likely to be the top thread too loose, I get comments like, “uh, no it’s not”, “are you sure?”, and my personal favorite, “I’ve been sewing for longer than you’ve been alive, I know what’s wrong with my machine…” (yes, I’ve had that one in real life.)

So, today I’m going to prove it – with a little help from you of course, since I can’t lay hands on your machine.

When this happens – don’t re-thread your machine yet.  Yes, I know that this is the conventional wisdom but we’re testing/proving something here.  Instead, pop your bobbin out and change it out for a bobbin with a different and contrasting color of thread.  Clear your thread jam if you need (but without re-threading the upper thread path except for the needle if your top thread broke), put the fabric back under the foot and sew for a short stretch.  The same symptoms will likely occur.

Change only the bobbin thread color for this test

Now pull your fabric out and look at the backside.  Which color is the thread mess in?

Now we see that the top thread has been causing all of the issues.

Now you might be tempted to say “See? The bobbin thread is a mess too!”  It’s not the biggest offender though, is it? That bobbin thread would be well controlled if the top thread was properly tensioned.

Poor Bob(bin) – He always gets the blame but it’s rarely his fault!

This is largely because of how a stitch is made.  In reality, the bobbin thread doesn’t really do much other than get in the way of the top thread traveling around the bobbin and get twisted into making the stitch.  This gif (should it actually move for you – click on it if it doesn’t so it opens in another window) shows how the stitch is made.

This image should be animated. If it’s not, click on it to open it in another window and it will move.

Seriously.  Pull your slide plate back, or pop the little bobbin cover and watch your machine make a stitch while it’s threaded with 2 different colors – hold your tails loosely when you do it though.  Removing the throat plate is probably unnecessary.  I only did it for clarity in the next few photos.  This is the same for a vertical or a horizontal bobbin setup.  As you’ll see, the bobbin thread isn’t really moving other than from friction of the needle thread passing over it, until the stitch is almost finished.

Beginning of the stitch
Middle of the stitch
Nearing the end of the stitch. Note the loop forming around the bobbin thread under the feed dogs.

In fact, that bobbin thread getting in the way is what causes this twist, which is what tells you a machine can make a stitch, even without putting fabric under the presser foot.  I rarely take fabric with me anymore – just needles and thread if I’m trying out a machine.  If I see this twist, I know it’s got most of its stitch mechanism intact enough to be viable.  If it doesn’t, it warrants a little more investigation before I choose to hand over any cash or to walk away.

The first day I truly saw how a machine made a stitch, my sewing life changed forever.  My sewing machine went from a magical and somewhat intimidating “black box” to something I could understand and reason my way through.

OK, so now that you know where to start looking – evaluate the upper thread path – and find the issue.  When you’ve done this, re-thread the machine to fix the issue.  Doing this will help you see where an issue likes to happen and watch for it in the future.

Note: In fairly rare circumstances, a minor version of this looping underneath can occur if the bobbin thread is not properly threaded into the tension spring but it’s very uncommon compared to the upper thread being routed wrong.   This is because there’s not nearly as much pull being exerted on the bobbin thread at any given point in the stitch process as there is on the needle thread so way less bobbin thread will ever be in play while the stitch is being made.

It’s also worth mentioning that typically a problem that shows up on the bottom is from the top thread and a problem that shows up on the top is from the bottom thread – unless one or the other thread is snagged on something.

This is how far I went to get the 411G to misbehave for you today.  I actually disassembled the tensioner to the point where no tension would be applied and it still sewed as well as you saw in the photos.  All tension control would have been provided by pre (before the tensioner) and post (after the tensioner) tension only. There’s a reason I love these vintage machines. 🙂

Tensioner – under no tension at all.

Boy it seems like I talk about tension a lot.  Ever wonder if there might be some stress in my life? 😉

What else would you like to read about? I’m looking for suggestions for future topics.  More on the spinning progress I’ve been making?  The woodworking progress? More techniques?  Long Arm stuff?  Heck, maybe I’ll even get back into the darkroom sometime soon.  Let me hear it!  Comment below or drop me an email with the contact link above – just know I might not respond quickly or I may just post about your topic if it was a topic suggestion only.

Today’s post title comes from Minnie Driver.  Yes, that Minnie Driver.  She put out an album in 2007 and Mockingbird was the first song I heard from it.  I’ve always liked the imagery in the song.  The title comes from this verse:

The color of desire is a wretched blue
It burns just like the center of a flame
It pulls the loosest thread inside your mind
It burns everything, but it calls you out by name

4 thoughts on “The loosest thread – Those pesky thread nests”

    1. Sounds good! I’ll blog as the urge takes me. I have been doing a lot of spinning and some woodworking to keep the older spinning wheels going. 🙂 Maybe I’ll put up some details about that and the new class I’m developing .

  1. This happened to me today – again. Hope it happens tomorrow so I can try your suggestion. And yes, I rethreaded the top thread. Keep these great tips,coming, please!

    1. Ha! You might be the only person I’ve ever heard of asking for their machine to make nests – but I hope it helps you out. 🙂

Pssst! I'd love to hear what you think about this!