Recently I attended classes from Renae Haddadin regarding longarming. We had a good hour of training learning about the importance of thread. A real eye opener for me. Then we proceeded to the machines and used a verity of threads and weights to see what the outcome would be. Superior thread was great along with so fine in the bobbin. Also Innovatech had good results. She uses polyester instead of cotton. I have always used cotton so I'm trying some polyester threads too. Always learning.