The use of a Union Special machine for hemming selvedge denim is essential for achieving the classic and authentic look that denim enthusiasts seek. This machine operates at a 45° angle, utilizing a chain stitch to create a distinctive roping effect at the hem of the jeans. This effect is highly valued by those who appreciate traditional denim construction.

The Union Special machine's unique ability to push and pull through the denim fabric creates a subtle puckering that contributes to the desired roping effect. This detail simply cannot be replicated with other sewing machines, making the Union Special an indispensable tool for achieving the desired aesthetic.