If you're new to free-motion quilting, you can choose between #50 or #60 weight cotton or polyester thread. And use the same weight for both the needle and the bobbin of the sewing machine. Later, you can experiment with different types of threads when you get comfortable with the process. You'll figure out sooner or later which threads are best suited for your quilts. In free-motion quilting, there is no standard rule about thread selection. It all depends on the quilter's personal preference.
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