Bit of a problem if anyone can help please.
I am sewing acrylic canvas and occasionally get a loop on top and getting a bit of pucker too, please see picture. I have adjusted tension, checked hook timing, stitch length etc I am now
wondering if there may be a mechanical problem with the machine or is there something I'm missing. The machine is a Brother LS2 B837. Needle is a 19/120. Thread is Coats Tkt 036
Many thanks