“It’s pi. The geometry of a circle hinging on the mysterious relationship of the circumference of a circle to its radius”, the words of my knitting hero Elizabeth Zimmermann. In this video, I demonstrate how to knit a flat circle.

Elizabeth Zimmermann’s Pi Shawl on Ravelry.

Instructions for working a Pi Circle:
Note: I use KFB increases below, you can substitute any other one-stitch increase.
Cast-on 8 stitches and join in-the-round on double pointed needles.
Round 1: Knit
Round 2: KFB all stitches (16 stitches)
Rounds 3-4: Knit (2 rounds)
Round 5: KFB all stitches (32 stitches)
Rounds 6-9 Knit (4 rounds)
Round 10: KFB all stitches (64 stitches)
Rounds 11-18: Knit (8 rounds)
Round 19: KFB all stitches (128 stitches)
Rounds 20-35: Knit (16 rounds)
Continue in this manner, increasing every stitch in the increase rounds, and doubling the number of plain knit rounds between increase rounds. Switch to longer circular needles as needed. Bind-off using a normal bind-off and a larger sized needle on what would be a plain knit round (not an increase round!).

The poncho on the mannequin is my Rodeo Drive Poncho, pattern and video tutorial.
The yarn I use in my finished Pi Circle is Roots & Rain Monsoon Sock.
The yarn I use for demonstration is Paintbox Yarns Wool Mix Chunky.
The DPNs I use for demonstration are Knitter’s Pride Ginger.