I also like strings of different widths. I usually use strings from 1" wide to 2 3/4" wide. I would not cut any lengths until you are sewing them onto the block, then just cut them as you need them. I like to use a thin paper foundation or a washable Pellon foundation cut into the size square you want for your block--I like 8" to 10" string blocks. The foundation really helps stabilize the edges of the strings and helps you know where to cut off each string. Here is my favorite string quilt.
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