[6] Slim stopped performing the blues for a time and eventually worked in a foundry in Pontiac, Michigan,[citation needed] as a result of which his hands were constantly exposed to high temperatures.

He was rediscovered by Fred Reif in 1970, in Pontiac, where he was living in a rented room at Slim Harpo's sister's house.

Reif soon got him back performing again and a new recording contract with Excello, this time through Bud Howell, then the president of the company.

His first engagement was a reunion concert in 1971 at the University of Chicago Folk Festival with Lazy Lester, whom Reif had brought from Baton Rouge in January of that year.

In the 1970s, Slim performed on tours in Europe,[5] including the Montreux Jazz Festival in Switzerland, for which he was often accompanied by Moses "Whispering" Smith on harmonica.