is your Brother a long arm? I have a long arm that hates Sulky thread--just shreds it so fast! Also, older thread sometimes frays, especially if it's cotton. Totally rethread and try the next size up needle. When my top tension is a little tight, it also can cause shredding. And I've also noticed that when I do a batik quilt, especially with batik backing, I have to loosen the roller tension to prevent threading. Good luck! So easy to get super frustrated when your machine is demented. So sorry about the loss of your husband.