I’ve known for a long time that the commercial blind stitching used for hems of many dress pants and skirts is a chain stitch, which will pull right out if you start it correctly (and knot up if you don’t). Just this weekend, however, I figured out how to reliably start it correctly.
If you look at hem stitching with the end of the pants leg downward, it looks like the drawing above: a series of horizontal dashes with little slanted teardrops extending down in between the dashes. The stitching will pull out to the right. If you can easily see what you’re doing, you can pick away at the loose end of the thread – the left-hand end of where the blindstitch overlaps itself – until the loose end is attached directly to a dash, and pull from there.
If you can’t easily see what you are doing, as was the case with me this weekend (busy fabric, probably inadequate light), you can still pull out commercial hem stitch. There are four steps, shown in the diagram: first, cut the thread toward the left end of a dash. Second, pull the dash’s thread toward the right. It will probably get hung up a little (if not, keep pulling!). Third, pick at the teardrop to the left of your cut in order to free the dash thread. Fourth, pull the dash thread to remove the stitching as far as it will go!
When you can’t start at the very end of the stitching you’ll need multiple rounds of pulling to remove all the stitching, but it’s still very quick – especially compared to a seam ripper!
Rice and grain bags often have a similar stitch, and once you master the stitch removal, it’s so much easier (and cleaner)!