Hello Sue,
I thgink what is happenning is the pin on the winder is not engaging with the bobbin if the winder is spinning but not catching the bobbin, you will have to physically bend the bobbin winder stop down a fraction to push the bobbin on a bit more, or if when you push the winder down to wind the bobbin the rubber wheel is not engaging with the balance wheel then you need to slacken off the screw on the side, push the winder onto the wheel and then tighten the screw up.
drivewithken, May 2009