I'm trying to replace a zipper in a heavy weight hoodie; tried #11 and #14 size needle with a heavier weight thread. Tension is set at 4 and have tried 4.5 and tried 5 yet I get a few stitches then a balling mess follow by a few descent stitch etc. underneath. the only good thing is it is easy to ripp. I have re-threaded and re-done the bobbin (using the bobbin and needles that came with the machine). Other suggestions would be greatly appreciated.
Make sure you are putting the needle in the correct way round, size 14 needle should be fine, make sure the bobbin is turning anti clockwise in the bobbin case, make sure the presser foot is up when you thread the machine.
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