They adjust for the stitches between gathers...and there are different rufflers out there....some have no settings and just automatically gather every stitch (the star setting on some), the "1" setting does a gather, stitch, gather...the "2" does gather, stitch, stitch, gather...etc.
I used this particular ruffler on the tree skirts that William and I made last year for Christmas gifts and attached 378 inches of fabric for a ruffle in, oh, about 5 minutes? Didn't really time it, but it didn't take very long.
William and Chip with one of the skirts we made.
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