I have been using an overlocker for years to tidy up seams with 3 threads. I’ve been stitching some stretch using a stretch stitch on my sewing machine and then overlocking the edges. BUT, I was wondering if I can just stitch with the overlocker and skip using the sewing machine for stretch? Do I then use 3 threads or 4 threads? What is the difference between using 3 and 4 threads? Is 4 threads less stretchy?
Also, does anyone sew all their garments with just the overlocker, not just stretch fabrics?