Jammed Sewing Machine? A Troubleshooting Guide

Making your own clothes and soft furnishings is a very rewarding hobby, as long as your sewing machine is playing ball!  Having your sewing machine regularly serviced and keeping it well-maintained should go a long way towards preventing annoying jams, but they can still happen.  Sometimes you can un-jam the machine yourself to keep it running smoothly between services. 

Here's a helpful troubleshooting guide to fixing your jammed sewing machine.

  1. Jams are often caused by tiny pieces of thread becoming stuck in the mechanism beneath the machine's foot plate.  Carefully remove your piece of sewing and snip away any obvious threads that are protruding.  Once the foot plate is clear, re-thread your machine, taking care to catch the thread in the correct place between the tension disks.  
  2. Using poor-quality thread can cause problems with jamming.  Cheap thread tends to vary in thickness and sheds lint as it passes through the machine, which can cause jamming.  Always use the best-quality thread you can afford to avoid problems.  
  3. If you use your sewing machine a lot, it will accumulate fluff and lint in its internal workings, and this can cause jamming.  When you have your machine serviced, it will be professionally cleaned, but you can carry out some DIY maintenance yourself.  Use a mini-screwdriver to unscrew the plate and remove it, together with the bobbin and holder, which should just lift out.  Use a small paint brush to carefully get rid of all loose bits of debris that are lurking underneath the plate.  
  4. A common cause of jams is an incorrectly wound bobbin.  Make sure that the thread on the bobbin is not tangled or loose, and trim off any loose ends sticking out of the bobbin top.  It's best to keep one bobbin for each thread that you use, rather than winding several different ones onto the same bobbin, which can cause tangling.  Replace the bobbin and plate, ensuring that the bobbin rotates in the correct direction.  Check that the thread has been directed through the spring in the bobbin holder.  
  5. A bent needle can cause your machine to jam.  Remove the needle from the machine and check to see that it's straight.  If it isn't, throw it away and replace it with a new one.  
  6. Jamming can be caused by sewing with an incorrectly-set tension.  Make sure that the tension set has not been dislodged and check with your machine's handbook that you're using the appropriate setting for the weight of fabric that you are working with.

When you've gone through all the checks outlined above, use a small piece of scrap fabric to test the machine.  If it continues to jam, you will need to have it inspected by a sewing machine repair specialist as it could be that the machine has a defective part that needs replacing.