I think it's probably the heaviness of the thread. I have this same trouble when I use a heavier thread than usual - the extra stiffness of the thicker thread makes it want to spring back from its turn around the thin bobbin, and makes it harder for the thread to hold the hitch. So it undoes itself. If you had much thicker bobbins, like say with a 1/4" (6 mm) thread shank, it would be more likely to stay put.
I seem to recall reading on this list how someone cut up plastic drink straws into length the same as their thread shanks and slit the straws open to make sleeves to fit over their thread shank and help clasp the thread in place. I wonder if that would work for you (the straw would have to be thin enough to firmly touch the thread all the way around the shank). Good luck. By the way, I use a double hitch on the thread shank itself. Still doesn't help much with the thicker threads. Adele North Vancouver, BC (west coast of Canada) > I am suddenly having > difficulty with runaway bobbins. > > I'm working on my large bolster pillow with 57+ pairs of > bobbins (boy are they crowded!). The thread is Filatu di > Cantu size 40, heavier than I usually use. I've had to use > every bobbin I own, so some are heavier and some are > lighter. Both the lightweight ones and the heavy ones have > trouble with the hitch. I use spangled bobbins and I put > my hitch on the thread, not on the head of the bobbin. - To unsubscribe send email to [EMAIL PROTECTED] containing the line: unsubscribe lace [EMAIL PROTECTED] For help, write to [EMAIL PROTECTED]
