[quote=Bennett]My sister called me and asked for a machine because she was wanting to use elastic bobbin thread for shirring, and her brand new machine had an automatic tension adjustment that wouldn't work with that.
Your sister can zig zag over a 1/8” elastic and secure the ends. Thread the elastic through a small straw or stir stick and tape it to the center of the needle to feed between the stitches. Even on modern machines you can adjust the bobbin tension to except the elastic thread. Just a suggestion.