I did find using Quilting needles were very helpful, made a huge difference. I just use the auto tension and keep the dogfeed up.[/quote]
When FMQ'ing the feeddogs should be down.
I really wish I could assist with the blue bobbin. I have a 6600 and haven't used a blue bobbin with it. I use my reg. bobbin and set my tension on 6 and have been good to go.