I use circles a lot. I have I like to do designs based on continuous curve (orange peel). I have several of DeLoa's circle buster rulers. When you do a design based on a circle, you have to move the template so that sometimes it's to the right and sometimes to the left of the foot. Unless you are ambidextrous, it may be hard to hold the template and sew. The Circle Buster rulers are made so they have an 'innie' and 'outie' side so you can always hold the machine with your dominant hand and easily hold the template with the other.
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