I too have a Bernina and am familliar with the bobbin race and the feed dogs clogging with lint. The first time I took my machine in and as I did not have the receipt for warranty purposes it cost me almost $200. Ouch. The next time I started having trouble I said to myself I AM WOMAN and got out my screw drivers and openned up the d$% thing and cleaned it my self and oiled it and massaged it! Now regularly between large projects I clean and oil the bobbin race and take of the front cover and inspect it and oil everything I can reach (dispite the brochure that says "never needs oiling".
MaryKatherine