Kenmore sewing machines normally make strong, even stitches when properly threaded. However, an improperly threaded Kenmore sewing machine will skip stitches, break the thread, and might not sew at all. It's not always easy to find a hreading guide for an old Kenmore sewing machine, but it is possible.
Many sites sell owners manuals online for around ten dollars, and at least one, Sew USA, has the threading guide portion of the information, for many models and brands, available for free.
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