Never heard of the dental floss trick before. I can see that lint would make its way into the tensioners.
I made
Girl's Joy last night and it is waiting for you in the appropriate thread.
It is #19.
I have the final Halloween batik fabrics waiting for me across the border. Unfortunately, because of the US holiday I can't pick them up until Tuesday. That is, if I can slip away from work a bit early. Wish me luck.