5 Steps to troubleshoot your sewing machine jams and tension problems

We’ve all been there – we’re merrily sewing away, marveling at our cleverness and efficiency,  when suddenly the sewing machine hiccoughs, growls and grinds to a stop, the needle juddering and jammed in the fabric, refusing to budge.  Underneath is a thick, complex knot of thread, reaching down into the throat plate and around the bobbin like a great tree root or something out of a James Herbert novel.

Jammed sewing machines are supremely frustrating, and are most likely to happen during a late night sewing session with a tomorrow-morning deadline.

Don’t worry, though – your machine is most probably not at fault.   A quick troubleshooting check of a few key areas on your machine will, in all likelihood, get you back into the sewing groove in no time.

So calm down, take a deep breath, wipe your sweaty palms, and pour yourself a brew. We can sort this out together.

Cleaning a top loader Text

Step 1: Re-thread the machine

Make sure your presser foot is up when threading your machine, to disengage the tension disks

Make sure your presser foot is up when threading your machine, to disengage the tension disks

Don’t be offended, I’m not suggesting you don’t know how to thread your machine – of course you know how to thread your machine, but sometimes things slip, or don’t sit in quite where they’re supposed to.  And the majority of tension issues and problems below the throat plate actually stem from incorrect threading.

Make absolutely sure your foot is up when you’re threading your machine.  I was guilty of threading the machine with the foot in the down position myself many times until I learned that unless the foot is up the tension plates won’t open to receive the thread, so as you continue to sew the tension plates aren’t able to do their job and you end up with tension problems.

Also, make sure that the thread is fully engaged in all the springs, slots and eyes that it’s supposed to be.  Give it a little tug through as you’re threading to make absolutely certain that it’s properly bedded in its channels.

Step 2: Change your needle

Did you know that you’re supposed to change your sewing machine’s needle after every 8 hours of continuous sewing?  This might sound like a lot, but your needle is used hard. It’s pushed through your fabric thousands of times at high speeds and will lose its sharpness in this time.  It will also get little nicks and burrs from sewing over pins and will start to bend due to being tugged back and to the side after you’ve pulled your fabric out from under the presser foot too many times.

Next time you change your needle hold it up at eye level and rotate it by its shank between your thumb and forefinger – if it’s an old needle the chances are good that you’ll see the wobble that comes from a crooked needle.  A crooked or damaged needle can’t catch the thread under the throat plate like it’s supposed to.  You’re more likely to have skipped stitches, dodgy tension, thread blockages, and maybe even a broken needle if the needles is bent to such an extent that it misses the hole in the throat plate and pings off at high speed.

Change your needle often, and make sure to choose an appropriate needle for your project

Change your needle often, and make sure to choose an appropriate needle for your project

So, change your needle often.  If you can’t remember whether you’ve sewn your 8 hours on a needle (and nobody can really keep track of this), change it every project, or at the most every 2-3 projects if you’re only doing small bits of sewing, but make sure you change it.

Take care to replace it with the appropriate needle for your project.  There are all sorts of needles for your sewing machine, different thicknesses and different eyes depending on the thread and fabric you’re using, specialist needles for embroidery, knits, leather, metallic threads, etc.  Check the packaging and use the appropriate needle for your project.

And screw it in tight.  Really tight, using that little screwdriver that came with the machine.  I’ve lost a few needles down my throat plate and some of them ended wrapped around the bobbin mechanism because I didn’t screw it in tight enough.  They’re a pig to get out and can ruin the timing on your machine.  And obviously this will ruin your project, too.

Step 3: Clean the machine


Check your machine over for little bits of stray thread that might cause jams – you may find some around the top part of the machine, around the thread guides, between the tension discs or around the take up lever, but don’t forget to check underneath the throat plate too – this is where you’ll find most sewing detritus.  Stray bits of thread or fluff can cause a world of problems when sewing so it’s important to keep your machine clean inside as well as out.

Open up the front of the machine if it’s a front-loading bobbin, or remove the throat plate if it’s a top-loading bobbin, remove both the bobbin carrier and the bobbin, and check the space for loose threads and fluff.  Unless you clean your machine regularly (which you should) there will be a lot of fluff in there.  There might also be a lot of fluff if you’ve been sewing with a very fibrous fabric, such as faux fur or felt.   You can use the little brush that came with the machine, but I prefer to use a stiff bristled paintbrush (the kids brushes are great for this) as the longer handle and thick bristles seem to be able to really grab onto the fluff and pull it out much more efficiently than the dainty little brushes that the machine manufacturers provide you with.  Plus they’re harder to lose.

Give it a really good clean, delve right down in there, and if this is the first time you’ve explored this part of the machine, and depending on your manufacturer’s recommendations, you might want to take this opportunity to drip a couple of drops of oil into the oiling holes, too.  Check your manual before doing this.

Cleaning under the throat plate of a front loading sewing machine

Cleaning under the throat plate of a front loading sewing machine

Cleaning under the throat plate of a top loading sewing machine

Cleaning under the throat plate of a top loading sewing machine

Don’t forget to clean in and around the feed dogs as well – they can get blocked up with layers of felted fibre, so it’s good to give them a quick clean while you have the brush out and the throat plate off.

Once it’s all clean in there, put the bobbin carrier back in and replace the throat plate.

Step 4: Check the bobbin

Ensure your bobbin is properly wound and inserted.

Ensure your bobbin is properly wound and inserted.

Are you using the right bobbin for your machine?  I’m sure you are, I just have to ask the question.  If you aren’t sure, check – bobbins might all look alike, but in reality they’re all different shapes and sizes; tiny differences in their dimensions and profile can have significant consequences in how a machine sews.

Is the bobbin tightly and evenly wound?  If it’s all spongy and untidy it’s really not going to work at all well – unwind that thread (or cut it out if necessary) and re-wind it, making sure that it’s winding nice and evenly.  Don’t over fill it, stop 1-2 mm from the edge.

If there are any bits of thread sticking out of your bobbin you must trim it off, even if it’s just a tiny little bit of fuzz.  In the same way that stray thread in the machine can throw your stitching awry, so can a tufty bobbin.

Replace the bobbin, making sure it’s inserted into its carrier properly.  If you aren’t sure how to insert the bobbin, check your manual.

Step 5: Talk softly to your machine

Give the machine a little wipe down with a soft cloth.  Just to show it that you love it and appreciate it, and would be really, really happy if it would start behaving now, please, thank you.  And try again.

If this all worked, high five! We sorted it, we are awesome – you are now practically a sewing machine mechanic!  If it didn’t, check the threading and bobbin position again, and if you’re still not having any joy you may need to take it in to your local service centre.

Step 6 (bonus): Have your sewing machine regularly serviced

You should be servicing your machine annually, even (or perhaps especially) if you haven’t used the machine for a while.  It isn’t expensive, my local service centre only charges £20, and having a properly tuned sewing machine will make your precious sewing time much, much more enjoyable.

I hope this is useful and will help you next time your sewing machine’s misbehaving.  Leave a comment, I love hearing from you!