Why Your Bust Arc And Back Arc Don't Add Up To Your Bust Measurement In Armstrong's System

A Comment Under My Last Note Sent Me Down A Rabbit Hole Last week I shared this note: “Most commercial patterns are drafted for a B cup in pattern making terms. That means the pattern assumes your upper bust and full bust are only 2 inches apart.” Mya B replied with a great question: “Wait, the bust arc and back arc aren’t supposed to add up to the bust measurement? That’s how I got my…