I have one machine that when winding the bobbin I have to put the bobbin on the winder upside down or it won't unwind correctly. Does that make sence? Anyway I love my sidewinder. I use it for every machine I have including my Tin Lizzie, it fills a new bobbin as you sew. When starting a new color and don't have anything to match on a bobbin, sidewinder will only fill about 1/2 of a size M bobbin but it works untill Lizzie has filled a whole bobbin.