Jay R. Luchsinger knew he was ready to start his law career the moment he was nearly crushed in the Loop by 15 tons of steel that fell 30 stories from a crane. Luchsinger, an ironworker at the time, was part of the welding crew working on the building at 181 W. Madison St. As a married man in his late 30s attending The John Marshall Law School at night while raising two daughters, Luchsinger switched from the raising gang — whose requirements include climbing columns while carrying upward of 30 pounds of tools …