Hi, I am new to this board but came here because I have had the same problems as Kris P except my machine is a Janome 9400 QCP. I just had it in for a "spa day" and took it back a couple of days ago because of the thread shredding, skipped stitches and all with the Westalee ruler foot. I was told in no uncertain terms it is not my machine though they replaced the bobbin case in the "spa day" and it seems loose to me. Anyway, I was reading online today all the things that have been suggested here about making adjustments but the ruler foot not being close enough to the material caught my eye. Also the advice about working with batiks. (They are more difficult because they have a tighter weave. I got out the free motion foot that came with the machine that I have used on a few quilts recently, not the hopper foot but the closed toe one and made a quilt sandwich with the batik I am using as a backing and the same cotton filler. I applied the 505 adhesive as I did with the quilt and tried it again. It is working fine. I have an Angela Walters ruler and used it. It working fine now. I think it is the Westalee ruler foot, that it does not keep the sandwich from pulling up from the stitch bed. Does this sound right to anyone? Has anyone had this same problem? I know Janome has come out with an up date which includes 4 new feet and a usb adjustment to the machine which causes the computer to recognize the feet. One of the feet is a ruler foot. It is $119.00 and Sewing Machines Plus in So Cal has the kit. I didn't buy it because I don't see a need for the other feet and I had already purchased what I have.