Do you have the 1/4 inch foot for your machine? That has saved me hundreds of times. Also i find that at the end of a seam I tend to pull my block away from the needle so I have a too narrow section. chain sewing with a piece of scrap fabric at the end has helped me with that. Are the shop hop stores close where you can take your block in and ask for advice. i was putting mine together wrong and once i was told, things went better.