Remember, you have to have the right size needle to go with the thread you choose. Superior Threads has everything you need to know about needles and threads. I use 50 wt. thread. It's thin and helps me with my scant 1/4" seam. The higher the thread number, the thinner the thread. A 40 wt. is thicker and requires a bigger needle. Go to
www.superiorthreads.com/ Hope this helps.