The first few stitches are just fine but then the machine seems to seize up and stops. When I try to remove the fabric I can barely lift it and then I must cut through a veritable bird's nest of threads on the underneath side of the fabric. The bobbin is loaded correctly and the bobbin tension seems fine. The top thread is also loaded correctly. The feed dogs are up and the needle down. I'm not sure what else to try.

you need to replace the needle again, is the needle the right one for the heavy fabric?

Hm, just guessing here.

Have you checked to make sure the walking foot (u-shaped) bar is still attached to the needle bar? Are the feed dogs still in the up position and operating like they should?

Learn How to Use Sewing Machine Walking Foot

Something else that I've run across in my sewing adventures is that walking feet need periodic oiling to keep them operating. Just manipulate the walking foot with your hands and watch where there are moving joints. Then apply a small drop of good quality sewing machine oil to each joint. Work it in and then wipe off the excess so it won't stain your fabric.

Lower the pressure on the feed dogs, use a stretch stitch, and longer stitch length. Be sure to use a good quality thread, and maybe go lighter weight thread.

I am assuming this is a simple stretch waist band with elastic about 2cm wide attached to a skirt or trousers. You need to measure your wist and cut elastic that length plus 2cm. Then join the two ends by overlapping them 2cm and zig zagging the elastic together with regular sewing machine. Now mark the elastic in quarters, ie hold it flat with the join in the middle and mark each edge with chalk or a fabric removable marker. Then put the marks together and mark the edges again so you have 4 marks equally spaced. Now do this for your garment too. It may be bigger in back so mark front and back, then half this to find the side quarters. Put elastic on inside of garment against raw edge and pin the quarter marks on elastic and garment together. Set up overlocker for 4 thread wide seam. Test seam and adjust tensions if necessary. Now you need to serge the edge of the fabric and elastic together, trimming the fabric but not cutting the elastic and stretch the elastic to fit the garment as you stitch. Elastic on top, fabric right side down underneath. Take out pins before you get near them! Start by lifting the front of the presser foot with your finger and placing fabric and elastic under, then start stitching on and straighten up once the seam is onto the elastic. Dont lift the pressure foot, you just stitch, stop, stretch the elastic to the fullness of the fabric, hold it and seam forward a few inches, then stop and repeat the process. Once right round go over your starting point, then turn and serge off the fabric edge and chain off. Cut, pull the chain to pull it flat and tie a hald hitch in it right up close to fabric. Now turn the elastic band to the inside of the garment. You need to secure it. Usually a straight stitch just onto the lower edge of the elastic with sewing machine from outside.

Hello,
Here are a few solutions to check.

* Check your fabric to make sure it isn't caught on something.

* Check your pressure foot to make sure it's screwed tightly in place.

* Adjust the pressure of your pressure foot as it may be too light or too heavy for your fabric.

* Check your feed dogs for lint. If your feed dogs are clogged with lint, they're not gripping your fabric properly. Remove your pressure foot and clean out any lint with an old toothbrush.

* Raise your feed dogs if your machine has this function. They may have been inadvertently lowered.

* Check your stitch length regulator, If its set at “0” or a very small number, try switching to a longer stitch length.

* Change your needle, it may be damaged.

* Check your needle plate and make sure it's securely in place.

* Use a “Jean-a-ma-jig” or a “Hump-jumper”. If you've been trying to sew over a bump of fabric, such as a thick jean hem, try using this tool (your local fabric store should carry it). It keeps your pressure foot level as you sew over the bump and gives your feed dogs something to grip.

I hope this helps

Check to see if the feed dogs are up, maybe you somehow clicked or switched a button, it happens to me some time when I take the bobbin out and put a new one in. I don't know your machine but some machines have the lever/knob for dropping the feed dogs in a strange location.

Increase your top tension, from 2 to 4, or from 5 to 6. Also check if there is no fluff or cotton in the top tension blades, preventing them from closing properly. Do this by lifting the presser foot and decrease the top tension to zero. This open the blades and allows you to inspect them. Good luck!

it sounds like you might need a new bobbin case to me try that and see if the issues you are having stop hope this helps

I had this problem but have resolved it (for the most part) by lowering the needle down into the fabric before beginning to sew.