It's a fair question for any band that makes a point of playing shirtless even in 40-degree weather, uses pentagrams and toy dinosaurs in its artwork and describes its music as "Motörhead inside of a gravity bong": How serious a band are you?

As the roaring sludge-metalists in Nightosaur ate through 90 minutes of digital tape during an interview at their rehearsal space this week, I never got the chance to ask about their sincerity. Nor did I need to.

You have to be pretty serious about your metal to go on and on about which Mastodon and Judas Priest albums are best, and which Iron Maiden and Alice Cooper show to drive to this summer. You have to be even more serious to build your own guitars, which red-bearded guitarist Andy Webber has done for himself, and for bespectacled, long-haired bassist John Henry.

"It's cheaper than buying one, and I can make it look the way I want it to," bragged Webber, who has started his own custom shop, Whale Hazard Unlimited.

Henry wholeheartedly endorses its product: "I didn't realize how much my old bass tone sucked until I started using [Webber's]. Too bad that was a year into the band playing gigs."

What really proved to me that these guys aren't kidding around, however, was their lengthy, track-by-track breakdown of their second album, "Spaceaxers," which they're promoting with a release party Thursday at the Triple Rock.

They described in detail -- and with no hint of irony -- which of their new songs is about a vengeful barbarian ("Warrior Bride") and a future being warning of Earth's destruction ("Porchburner") and an Antarctic mission gone amuck ("Too Far South for Mutiny"). The latter song might also be about their rather dismal tour of Texas last year, which was when former guitarist Max Clark started a slow, amicable exit from the band. He stayed through the making of "Spaceaxers."

"We tried auditioning a few other guitarists, and may still add one," Webber said, "but for now, we're having too much fun as a trio. There's more space for us to [mess] around."

Nightosaur's members, ages 29 to 32, took their sweet time becoming full-fledged metal musicians, but they all grew up on the hard stuff.

"I hadn't really listened to metal since Metallica's 'Black Album,'" Henry said, pinpointing the moment when a lot of other metalheads lost interest in the music. "I realized how much I really missed it."

Apparently he wasn't alone. Webber said they have had great luck "bringing out the inner metalhead in everyone" at their shows. They often play at true metal breeding grounds such as Station 4 nightclub or biker rallies, or in more punk and indie-centric clubs such as the Triple Rock or Turf Club. At the latter venues, Webber said, "A lot of times we hear, 'I'm not really into metal, but I like you guys.'"

Their first-ever gig was on a sweltering July 3, 2010, in a basement "where the walls were sweating as much as we were," Henry remembered. Hence the decision to perform shirtless -- a practice that stuck, for better or worse. That's just part of Nightosaur's rowdy, signature shows, where the sly smirks on the guys' faces and their pseudo-rock-god mannerisms might also be misconstrued as a novelty.

"The key to being a good band is to have more fun than everybody else in the room," preached Henry, a former member of jokey rap duo MC/VL.

As for the other facets of the band that may seem cartoonish, like the fantastical songwriting, the bassist said, "So much of metal is about teenage male fantasies, wizards and demons and shirtless warriors. It's as big a part of the music as the riffs. And we love that music."

No question.

Tangled up in Bowe

Currently the bandleader for Alison Scott, jack-of-all-trades Kevin Bowe called in a lot of his older friends to help craft his own rollicking, rootsy, Dylan-heavy album, "Natchez Trace."

Participants include Paul Westerberg and Wilco's Nels Cline, each of whom had a hand in the not surprisingly Replacements-sounding "Everybody Lies," plus Chuck Prophet, Freedy Johnston, Rolling Thunder violinist Scarlet Rivera and members of Communist Daughter and Farewell Milwaukee.

The only guest we know will for sure show up at Friday's release party at the Varsity Theater is Scott, who also has a new album: "Hiding Under the Covers, Vol. 2," featuring piano-soul remakes of songs by Tom Waits, Elliott Smith, Led Zeppelin and Radiohead (8 p.m., $15).

Random mix

Remember the Deep Blues Fest? The way-cool gathering of hidden-gem, rural-blues and bluesy punk bands will be revived June 29-July 1 at fest founder Chris Johnson's new place, Bayport BBQ, just south of Stillwater. Performers include the Alabama Shakes' current tour opener, Lee Bains III, plus Buffalo Killers, Purgatory Hill, Welsh band Henry's Funeral Shoe and many more. Advance passes are on sale through Sunday. Details at BayportBBQ.com. ... Today is also the last day to get passes to Somerset's SoundTown fest at the $80 advance price. ...

The Electric String Quartet, a string-looping ensemble led by violin whiz kid David Gerald Sutton, will promote its debut album Tuesday with a release party at Overcomer's Victory Center, 119 Lyton Place, St. Paul (free, 6-9 p.m.). It's a concept record about Alzheimer's. ...Nightosaur got rained out in this week's kickoff of the Wednesday-night Cinema & Civics series in Stevens Square Park. Me & My Arrow is scheduled to perform next Wednesday before a screening of "The Blues Brothers" (8 p.m., 18th St. & 2nd Av. S., Mpls., free). See the full lineup at www.CinemaAndCivics.org. ... Music in Mears is also now underway in downtown St. Paul. Communist Daughter, the Sans Souci Quartet and Caleb Hawley perform at the free weekly gig next Thursday (6-9 p.m.). More at www.MusicInMears.com. ...

While its Monday gigs with the Cactus Blossoms continue to, you know, blossom, the Turf Club has its biggest Tuesday night residency yet for the month of June with Dead Man Winter and Retribution Gospel Choir. Yep, both of them for the next two weeks (9 p.m., $10). Sold.

Follow Riemenschneider on Twitter: @ChrisRstrib