Martin , looks like you are getting some good advice . I certainly understand the frustration of using a sewing machine . I've discovered that I would have better luck building the Space Shuttle than using a sewing machine . 
Although , I can offer one suggestion . In my line of work which is Facilities ... i.e. construction and building maintenance ... we have a " standard operating procedure " when it comes to equipment . You hit it once for maintenance but twice is abuse .
Mike Montgomery
Clan Montgomery Society , International
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