My issue is the induction area is smaller than my pan and cast iron conducts heat poorly, so only the middle ~7" of my 12" pan is hot, the rest is downright col

My issue is the induction area is smaller than my pan and cast iron conducts heat poorly, so only the middle ~7" of my 12" pan is hot, the rest is downright cold. Though my cast iron wok heats properly, for almost the same reason!