I tried everything to get straight seams. Measured, marked, basting, pinning, etc. One day while sewing, I finished quilting a small quilt, and went to start strata for the next quilt. I was shocked to see my seams perfectly straight! That's when I noticed that I had forgotten to reset my machine speed to normal after I had it at half speed for the walking foot. Who knew that by sewing slower, my stitches would be nice and straight?! (I learned to sew on an industrial machine, so I thought home machines were slow.) If you haven't tried this, give it a shot, it works for me.