Pinhole Cast On for Flat Knitting
The pinhole cast (aka the circular cast on, invisible circular cast on, or disappearing cast on) is most often used to cast on a few stitches, 12 or less, when you'll be knitting a project in the round and gradually increasing how many stitches are on your needles. I often use a pinhole cast on when I am knitting toe up socks, and it also works nicely for hats that are knit from the top down.
However, the pinhole cast on can also be used when you're casting on a small number of stitches and working flat back and forth in rows like you would for a triangular shawl like my Duck Pond Shawl.
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