It’s the oldest imperative for performers: Let’s put on a show. Maybe that explains why two amateur rock bands, made up of professionals in other fields, are joining forces in the “Rock for Heat” concert, set for 8 p.m.-midnight Saturday at the Bangor Banquet & Conference Center, on Hogan Road.

No, the RetroRockerz and the Jack Cashman Band aren’t playing to keep warm. Instead, they’re providing their talents for the donations-only event to raise funds for the Bangor Fuel Society. The society is a century-old, nonprofit organization that provides heating assistance to Bangor residents and the surrounding communities in need.

Except for one professional guitarist, these musicians all have other careers. In the RetroRockerz are a teacher, a bank president, a counselor, an orthopedic surgeon and a member of the legal profession. The Jack Cashman Band has two state officials, a restaurateur, a teacher and Mark “Guitar” Miller on lead guitar.

The idea came from the RetroRockerz, explained Jim Dowe, a guitarist in the band and the president of Bangor Savings Bank.

“We’ve been playing together for a few months,” Dowe said. “They’ve all been charity gigs, because no one will pay us to play. We decided to set up a benefit concert, because it’s nice to have something to look forward to, because it makes you play harder. But what could we do? Well, people are struggling to pay for fuel, so we called Cal True [of the Bangor Fuel Society] and asked if they would take the money raised.”

True readily agreed.

“I told Jim I was grateful for him thinking about the need that exists in the community, given the high cost of heating oil and what was expected to be a long, cold winter, and the limited amount of funds available to help those in need,” he said.

Beside Dowe, the other members of the RetroRockerz are vocalist Joe Bennett, guitarist-keyboardist Andy Mead, bassist John Bradford and drummer Eric Taylor. Dowe said the band plays covers of classic rock ‘n’ roll songs from the 1960s and ’70s, occasionally venturing into the ’80s.

Cashman, the state’s Commissioner of Economic and Community Development, got involved because “it’s a good cause.”

The Jack Cashman Band is made up of Cashman and Miller on guitar, his son Dan Cashman on bass, George Gervais on drums and Mike Scarponi on sax. The group plays blues and older rock ‘n’ roll, Cashman said. All but Miller have been playing together since 2000, but, Cashman admits, “now we play only a few times a year.” yeyear.”year.”

In addition to the two sets of music, a small auction is planned. Items up for bid include the services of the two bands, signed Stephen King books, fuel gift certificates, an overnight stay at a resort and RetroRockerz and Jack Cashman Band T-shirts. Hors d’oeuvres from Gervais’ Chocolate Grill and Evo Italian Brick Oven restaurants will be served. There will also be a dance contest, and perhaps door prizes.

Dowe said the two groups hope to raise $5,000 for the fuel society.

“This started out informally, but it’s taken on a life of its own,” he said.

For more information, call Darlene Hawkes, Bangor Savings Bank, at 262-4954. Dale McGarrigle can be reached at 990-8028 and dmcgarrigle@bangordailynews.net.