usually if the machine is jamming up it is due to tension problems, I would check this to begin with, when you thread the machine make sure the presser mfoot is up so the thread goes in betwwen the tension discs, it is very easy to have the thread go the wrong side of the discs, top tension between 4 and 6 should be okay.
Bottom tension should be enough to pull the thread through with some resistence, open the slide plate and turn the balance wheel towards you whilst the machine is threaded top and botton to make sure the bobbin thread is passing through the gap to form the stitch, make sure there is no damage on the bobbin case, make sure your needle is in the correct way round.
drivewithken@blueyonder.co.uk, November 2007
