Dan Siskind rummaged through bins full of assorted Lego pieces, searching for just the right one.

At last he spotted it: a thin red brick he snapped snugly into place. Then it was back to the endless row of containers to dig for more parts. Brick by brick, his intricate model of a World War II German tank began to take shape.

It may seem like child’s play, but Siskind’s custom-design military kits are big business.

“I used to make 10 of these,” he said. “Now I’m making 100.”

The ex-punk rocker and former record label owner is “commander in chief” of Brickmania. From his command post in northeast Minneapolis, he supplies a small army of fellow Lego enthusiasts from around the globe with military- and battle-themed kits.

Siskind recently opened a store in the Mall of America, where one of his most talked about projects is on display: the battleship Missouri — a 26-foot-long replica of the World War II vessel on which the Japanese surrender documents were signed in 1945. It’s one of the largest model ships made from Lego bricks in the world.

But then, Siskind has always dreamed big.

As a boy, he built Lego castles that covered his bedroom floor, said his mother, Sylvia Gubbe.

“What he really wanted to do was just build things,” she said. “He’s had a lot of iterations, when he’s failed or succeeded, and he just keeps on going.”

He dropped out of high school, joined a few punk rock bands and toured Europe. That was the early 1990s, a time when he sported dreadlocks, a nose ring and performed with Minneapolis bands Pissed, Disrespect and Destroy. For years, he also edited the country’s largest anarchist Punk fanzine, Profane Existence, and ran a record store, Extreme Noise, on Lake Street.

Now 44 years old, Siskind wears his hair short, and the piercings are gone. The married father of three teenagers often dons a simple black hoodie with the Brickmania name on it.

While there are remnants of his punk days — large dragon tattoos cover both his arms and a sticker on his computer reads: “This machine kills fascists” — he says he’s left the scene behind to focus on building his company.

He may have grown up, but he hasn’t outgrown his childhood passion.

“I never stopped playing with Legos,” he said.

Building in secret

Long before he started his business, Siskind kept his Lego building a secret hobby. Only people invited to his house would see his elaborate projects, which eventually filled the basement.

In the 1990s, the emerging Internet enabled him to connect with other adults who enjoyed their Legos and wanted to build more advanced models.

“I was interacting with like-minded people from all over the world,” Siskind said.

In 1999, he designed a medieval blacksmith shop, which was a hit in the Lego build community — so much so that the Lego company bought the set.

At the time, Lego had been selling simple sets in primary colors aimed primarily at kids. Adults who contacted the company to ask for parts or suggest an idea for a set were ignored, Siskind said. “They treated you like you were a lunatic.”

Lego hasn’t purchased any of his military designs, though. To avoid trademark issues, he must market his kits as “building sets made from Lego bricks.”

“Officially, I think they just want us to go away,” he said of Brickmania. “I talk to their lawyers regularly.”

The Denmark-based company makes Civil War battle kits and sells fantasy warfare, but when it comes to more recent wars, Lego doesn’t play around.

“To facilitate a child’s natural urge to explore and understand conflict through play, we anchor tension in Lego story lines in fantasy, and we refrain from depicting real-world battle, war themes, vehicles and weaponry,” said Michael McNally, Lego’s senior director of brand relations, in a written statement.

Siskind understands that war is a serious subject, but he doesn’t see the harm in making toys that help history come alive. “Why would you separate play from teaching history?” he said.

Willy Wonka for toys

Once a month, the Brickmania headquarters in northeast Minneapolis hosts an open house. For a fee, kids of all ages can enter the Brickmania Toyworks room to see the Lego creations on display.

“This is like our Willy Wonka toy factory,” Siskind said.

At last month’s open house, kids pointed excitedly to the sprawling and complex reconstructions of famous battle scenes.

“I know which battle this is!” 10-year-old Evan Connolly announced. “This is from World War II, Mom.”

“He’s Mr. History Buff,” acknowledged mom Jen Connolly.

Most kits are World War II-era, because that’s what people want, Siskind said. His bestselling kit by far is the Sherman tank, the ubiquitous American combat vehicle from that time.

Another collector item is the Family Truckster kit, modeled after the wood-paneled station wagon and Griswold family members from the movie “National Lampoon’s Vacation.” (Beverly D’Angelo, one of the movie’s stars and a customer, autographed the box of the kit that’s on display at the warehouse.)

Siskind relies on his own research and imagination to come up with the design for the military-themed kits, which range in price from $10 to $500 and in level of difficulty from “new recruit” to “veteran.” He spends hours at his desk poring over military textbooks, among them “Pacific Warriors” and “Stalin’s War: Soviet Uniforms and Militaria 1941-45.”

On a recent weekend afternoon, techno music blared while he worked in his office. He was accompanied by Mr. Furley, his pet boa constrictor, housed safely behind glass in a cage made out of Lego Duplo blocks.

Building his company, he said, is much like building one of his models.

“You have to think ahead — how are you going to attach something?” Siskind said, as he examined the half-assembled tank in his hands from different angles. “It’s a lot of trial and error.”