Tim Gunn (Ian Maddox for The Washington Post)

It’s hard to imagine anyone hating America’s mentor, Tim Gunn — the beloved confidant and adviser on “Project Runway.” But the reality star and real-life sweetheart confessed that he ruffled a few feathers after taking the helm at Parsons the New School for Design in 2004.

“I have to tell you, I was not the most popular person on 7th Avenue,” Gunn told audience members at a Smithsonian Associates event the National Museum of the American Indian on Wednesday night. “Repositioning the Parsons program, I made a lot of enemies. A lot.”

Fashion, Gunn said, has to change. A lesson particularly pertinent to D.C. Gunn eventually won the majority of critics back after he revamped the storied Parsons program, which he said hadn’t been changed in 50 years.

The longtime teacher and D.C. native has channeled his lessons from Parsons and “Project Runway” into his latest book, “Tim Gunn: The Natty Professor — A Master Class on Mentoring, Motivating, and Making It Work!”

Another fashion lesson that folks could make “work” in Washington? Leaving your personal gripes at the door and getting it done.

“I think that is why I was successful repositioning the fashion program because I didn’t have an axe to grind,” Gunn said. “All I cared about was quality, and I cared deeply that the curriculum that we were putting in place would prepare a new generation of leaders.”

Gunn’s efforts have largely paid off. Jack McCollough and Lazaro Hernandez of the lauded brand Proenza Schouler were among the first graduates of his revamped program. Jason Wu and Alexander Wang are among the other notable students, though neither graduated.

And, of course, a night with Tim Gunn wouldn’t be complete without some fashion critiques.

“I grew up in Washington, so I know it’s not a fashion town,” Gunn joked. “I’m asked, ‘What’s wrong with people on Capitol Hill?’ Well, I can think of a million things. But when it comes to fashion, I’m always looking at Nancy Pelosi thinking, ‘How fabulous is she?’ Look at Mrs. Obama, why can’t people take note?”