The Geometry of a Crochet Hexagon Cardigan
The granny hexagon cardigan (popularized as the "Campfire Cardigan" across TikTok and Pinterest) is beloved because it requires almost zero shaping while crocheting. You crochet two large, flat six-sided hexagons. When you fold each hexagon in half, the geometry forces it into an L-shape:
- The horizontal branch of the "L" folds into a tubular sleeve.
- The vertical branch of the "L" forms one side of the front panel and half of the back panel.
- When joined at the back seam and shoulder seams, a complete jacket is born.
Why Standard Patterns Fail Larger Bust Sizes
In traditional crochet patterns, instructions often tell you to "crochet until the front panels meet in the middle." Because a regular hexagon expands equally on all six edges with every round, adding 6 extra rounds to gain 6 inches in the chest also increases your upper sleeve circumference by 6 inches! For makers with a D-cup or plus-size chest, the sleeves end up wide enough to fit both arms inside one sleeve.
The mathematical remedy is simple: stop adding hexagon rounds once your sleeve width is comfortable, and work straight rows along the inner back edge. This widens the back of the sweater across the shoulder blades without touching the sleeve dimensions.