To cheerio. the birds' nests, etc. are a tension problem--my son's answer to that is to use the same thread for the bottom that you use for the top; do a sample run before you do your quilting; there is a certain way to put the bobbin in, try it out, let it hang from your hand and fall free (not so good at explaining here); try it and see what happens. If you still have questions, PM me, and I'll have Bryan try to explain it to you.