Painted in tribal body paint and stacked six deep on the stage, armed with an instrument that looks like a post-apocalyptic weapon, Motograter is the kind of band that would look right at home performing in the Thunderdome. Motograter, formed in 1995, is named after its signature instrument, a four-foot-long steel beast formed from the remains of a child’s swing set, screen-door springs and industrial cable. It is played with a drumstick and produces a rich bass sound that they call “pure evil.” The motograter was conceived of and built by Bruce “Grater” Butler, one of the band’s founding members and the longest lasting of the original tribe. Originally, the motograter replaced the guitars in the band. The resulting sound was unique to the nu metal genre and helped the band solidify its place in the hierarchy. Songs like “Suffocate” exemplify this, with a bass line that starts out almost generic but quickly takes over and forces the sound right into your bones. The instrument also helped them produce a deeply tribal and aggressive sound that set them apart even more. The band started out as a percussion-heavy four-piece, but picked up two additional members around the time they released their second EP, “Indy” — a guitarist and someone to handle electronics and samples. Over the next four years they would shuffle through members, including three years with Ivan “Ghost” Moody (who sang with Five Finger Death Punch) on vocals, until they finally called it quits in 2006. They reformed three years later with nearly all new members and an updated sound. The new breed of the band added a bass player to back up the motograter, resulting in an even fuller-bodied low end. This is offset by the reduced focus on percussion, which gives the current incarnation of the band a sound unique to its new lineup but with the signature motograter sound fans expect to hear. “We’re heavier, a lot heavier, with more of a modern-metal sound,” said vocalist Michael Woodruff, who’s known as Angel. “There’s still that tribal bass, but with more breakdowns.” Regardless of who the band members were, or are, two things remain consistent: the motograter and the tribal paint. It goes without saying that the Motograter wouldn’t be Motograter without the motograter, but the tribal paint isn’t just an added gimmick. “The makeup is part of our ritual. It starts almost an hour before the show and we put the mud on 15 or 20 minutes before we start,” said Angel. The paint gets the band into the show mindset and helps them connect onstage. The paint has been known to get them in trouble, though: Having tribal paint on your entire body makes it difficult to keep things around you clean. At Birch Hill in Old Bridge, N.J., the band made such a mess they ended up having to repaint the dressing room for the venue. They receive frequent complaints, but there aren’t any plans in the future to get rid of the makeup. Along with the instrument, it’s one of the things that make the band what it is regardless of who’s on stage. Motograter’s current lineup is anchored by Matt “Nuke” Nunes on guitar. The resident veteran, he’s been with the band off and on since 2002. Angel, Tyler Hole (guitar), Mylon Guy (bass) and Jeremy “Twitch” Scheller (drums) are the core of the “new breed,” and have been with the band solidly since 2008. In 2009, Brad “Grater” Butler left the group and Mark Nosler took over on the motograter. An EP, “Pre-Release,” was produced in 2009, but Motograter are using the current tour to inspire a full-length album. A studio is too antiseptic for a band that prepares for a show by donning war paint and tuning up an instrument that could double for a weapon in Doom. They’re looking forward to heading east, where the crowds are better and more responsive. You can join the tribe and succumb to the sound of the motograter at The Carriage House (9033 Columbus Rd. NW, Louisville; 330-875-8101; carriagehouserocks.com) on May 19. Tickets are $10 in advance, $12 at the door.