A modern Singer sewing machine which has gone out of synch. We replaced a broken part and adjusted it and then it worked well for a while, but it keeps slipping out of synchronisation between top and bottom thread. I guess that whichever screw it is, is not tight enough.
After opening it and adjusting it umpteen times only for it to slip again, I am now officially fed up and somebody else can have a go. I can explain what you are aiming for.
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