What is the problem when sewing the top thread can be pulled right out and the material puckers up

Tighten the top tension. However, if the bobbin thread is actually pulling up on the top of the fabric, the bobbin tension is too loose. Both top and bobbin threads should pull enough against each other that they meet in the middle of the fabric without causing puckering.

Another thing to remember. ALWAYS RAISE the presser foot when threading the top thread!

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increase the top thread tension up a bit
it is known as "bird nesting" and indicates that the top thread is not pulling the bobbin thread up tight
needle thread tension is NOT a "set and forget" item as different thread thicknesses , material thickness and needle eye size all have an impact on the tension and it has to be change to suit

Most sewing machines will cause puckering when zig-zaging, especially when sewing light-weight fabric like chiffon, etc. Try a brand new needle. You can try narrowing the zig-zag so there is not such a large gap between the left & right swing. Can also try loosening the tension a bit so the thread is not pulling so tightly. Another possibility (if your machine has the capability) is to increase the presser foot pressure so there is more pressure applied between the presser foot and the feed dogs. Or, try using a layer of wash-away stabilizer or clean (unused) newsprint paper with the fabric to help give it some stability.

How to Adjust Sewing Machine Tension on Craftsy

How to Prevent Your Sewing Machine from Puckering Fabric Howcast

https://groups.google.com/forum/#!topic/alt.sewing/AOhNY36JOa0

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Go back to the tension adjustments that were doing well with other fabrics.
You may need to go to a smaller size needle, and a finer thread. Sometimes I use a wooly nylon in my looper because it is very stretchy, but be careful when you pull it through as you are threading it because it will also break easily if you don't have your tensions full open as you are pulling it through.
Start out by buying a sheet or roll of Solvy. You can either cut it into strips to lay on top of the material as you sew or under it if you prefer. It should make the material lay flat as it sews. I have used tissue paper before under it to make it lay flat and keep it flat to make the looper thread stretch itself out as it sews.
If your looper thread tension was too tight on other fabrics too, that is a whole other problem.

You may have the wrong bobbin in the machine.

#1 Use only Mettler or Gutermann thread. Coats thread is very rough and will pucker the fabric. #2 Make sure that the tensions are balanced. #3 Use the regular zig zag foot. #4 Use a new needle, universal, size 80/12. A blunted point will pucker the fabric.

If your material is puckering then the thread tension (Top and Bottom) are way too tight. Loosen both.

Good Luck!
Chris
glfi.com

The proper tension is a tension that locks the threads together tightly (you don't see a gap in your seem when you pull the two separate fabric pieces apart after sewing). But the biggest problem I see is when people have the thread tension so tight that it puckers the fabric as it's sewn. Thread tension is a balancing act between three forces top tension, bobbin tension, and fabric

Hope this helps...
Chris
glfi.com

You could try loosen the tension on the upper thread to 2.5-3.0 or Lengthening your stitch to 3 or 3.5 should also help.

you should always use needles that are the right size and sharpness for different fabrics. any fabric store can help you with this. according to your machine the smaller the # on the needle the finer teh fabric it will sew. also using the right weight of thread is important...light weight thread for light weight fabric and heavier for thicker fabrics