Rocsew, do you have a FW rotary? There is some concern on the ratio between thread hole and needle tip that makes it different from the regular 15x1 needle. It might interfere with threads interlocking properly If it works for those who use this model on a regular basis I guess a needlebar adjustment might be the way to go. The advantage with a regular 15x1 needle is the selection of sizes and tips available (sharp, butted, leather, etc).