I have a Pfaff, and I'm having trouble hemming jeans with heavy thread (jean thread). The underside of the fabric looks terrible. I've adjusted the tension, but still can't get it to look good—the best I can get is a crooked stitch on the bottom, but it looks great on the top. What’s wrong?

How do I know which letter code/category of machine accessories will work with my machine?

What is the purpose of the PFAFF® Original IDT™ system?

Where do I find the updates for my machine?

Where can download complimentary software for my embroidery machine?