Singer XL-580 Manual De Instrucciones página 62

up the fabric in the center of the buttonhole.
Be careful not to cut any of the bartack threads.
spur and pull both ends of the cord forward under the foot and
tie off the cord as shown in the illustration.
When completed, release the cord from the foot and snip off
the extra length.
If desired, instead of snipping off the extra length, bring them
to the back side with a large hand needle, then tie to secure.
When buttonholing with hard-to-sew fabrics or along the edge
buttonhole foot as illustrated to make perfect buttonholes.
Place the fabric between the under-plate and buttonhole foot.
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