I solved a mess of bobbin winding problems with my 1941 Singer by buying a Sidewinder----a little machine that only winds bobbins. While my machine would still wind a bobbin if I worked with it long enough, the SideWinder can wind about one bobbin per two minutes with no hassles. It's about $30 unless you catch a good sale at Michaels or JoAnn or Hancocks like I did. Definitely worth the lack of stress and frustration on my part!