While the nation had no idea what would be on Ms. Franklin’s head, Mr. Song knew it would be one of three models she had picked out. He learned which one only while watching her sing at the inauguration on the television in his crowded workroom.

“I’m so glad she chose that one.” he said. “It was the one I was pushing her to wear.”

Interest in Mr. Song’s work has exploded so much that he expects his business, Moza Incorporated, which recorded $1 million in sales during 2008, to do six to seven times more than that this year. Mr. Song would like to double his workforce, currently at 11 people, if he could find more experienced seamstresses.

The only hitch, he said, is that millinery “is a dead art.” And indeed, Mr. Song, who estimates that he is one of about a dozen custom milliners in the country, is, in a sense, an accidental milliner.

Image Delois Dawkins of Flint, Mich., shopping at Mr. Song Millinery in Detroit, where each piece is hand-sewn. The shop had a local following long before January.

As a young man, Mr. Song, 36, had no intention of taking over the business his parents, Han and Jin Song, started after emigrating from South Korea in 1982. After studying biochemistry in college, he left one semester short of a degree to pursue art studies at Parsons the New School for Design in New York.