Your cutting has to be exact. Your sewing has to be exact. You probably need to go SLOWWWW for a while to get that exact 1/4". I was really very overly cautious and slooowwww for months when I started quilting. Finally my skills developed so I can go fast...this after 5 years of quilting. If you are a new quilter it's your own learning curve. Take your time...accuracy is so much more important than speed.
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