I have a 26" Tin Lizzie Ansley LS and am going on 7 years with it. I use Signature and Connecting Threads Essential Pro most of the time. I've got a few spools of King Tut and have no trouble with just about any thread I've tried. I love this Lizzie, it's a real work horse, never a tension problem and it always runs smooth. Let us know what machine you have, maybe there is something machine specific we can help with.