Thought this might be of interest...I needed 3 threads for the coverstitch and 3 for the overlocker. I use large cones to sew with so needed a simple way to transfer the thread.
Take a Gutterman spool, pull out the bottom, glue it to a bobbin, make a paper sleeve, fit the sleeve over the Gutterman spool and whizz away!... hold the thread and slowly move it up and down so the thread is evenly distributed ...hey presto 6 extra spools in no time