Except for my embroidery machine ( on which l use machine embroidery thread), l can use any thread l like on my computorizedJanomie 6500, my blind hemmer, my Bailey 15, and my daughter's little computorized Brother 6000i, and my old White Jeans machine. I've learned to set the tensions, and use the appropriate needles. I think that those who have machines with automatic tension control probably find them the most finicky .