I am wondering about my stitches. They seem variable when nothing has changed. Most times they seem okay. But then an occasional stitch seem kind of off. Or when the stitches were clearly define, all of a sudden, they kind of meld into one line. Or there is the occasional tiny loop on the back of the fabric. Or 1 or 2 stitches out of line. When nothing has changed. I have checked the needle (flat side to the left). I have re-threaded. Checked the bobbin. Does this happen to you? Or what am I missing that I need to check or adjust?
I was wondering - do you find your 15-91 to be particular with thread type?
Below are pictures of what I am seeing. 100% cotton. Kind of thinnish material. Actually, these stitches look more consistent on this than on some slightly thicker 100% cotton. Do you find that you need to adjust tension when then material gets slightly thinner or thicker (I only quilt right now, so always 100% cotton). First picture is of the back, second one is of the front.