Hello Georgina,
I take it that you have checked all the basic things such as making sure the tension is set properly top and bottom, if it is still breaking thread check the needle plate for any rough edges, check the bobbin case for any sharp bits and also the raceway, if everything is okay you may need to retime the machine but I would go for the tensions first, if you need to retime it I can attach timing instructions if you e-mail me.
Ken
drivewithken@blueyonder.co.uk, September 2008
