I discovered years ago when embroiderying or doing crossstitching I could use a toothpick with a teeny, teeny amount of Elmer' s glue to swipe the tail(s) of my embroidery floss and then secure it to a few already worked pieces of floss on the back side of my projects. It sure eliminated all those ugly knots. Have pieces 20 years and older with no unraveling. I do wash all my work when completed so I use regular glue.....NOT washable school glue for this.