I am assuming you have unthreaded and rethreaded making sure everything is threaded right. I am assuming that the loops and bird's nests are on the back of the quilt or on they on the top? Does the loops and nests occur when you are moving in a certain direction or do they occur only in a certain position...like at one end of the quilt, the middle or near the back of the take up roller.> Is this something new. Size of needle.? It is helpful to know the specifics so we can give you some hibts,