Off a narrow dirt road tucked into the hills northeast of Craig, John Ilko sets up the palette and mortar for his son, Johnny, who hustles back after lighting the fuse with a propane torch.

“Fire in the hole!” John shouts.

A deafening bang and thick cloud of smoke result from the two-inch salute shell, the least of the men’s toys.

“I’m glad we have neighbors who like us,” said John’s wife, Sally.

John Ilko Jr. has been fascinated with the chemistry of fireworks since a young age, an interest he since has passed on to his son, John Ilko III, or Johnny.

“It’s been a passion since I was a little guy, 10, 12 years old,” John said about dabbling with a Gilbert chemistry set. “Chemistry sets back in the ’50s were real chemistry sets. They had definitely hazardous materials.”

He remembers one occasion in particular when he caused some trouble with those substances. He and a friend were making smoke using zinc dust and an oxidizer.

Smoke filled his basement in Philadelphia and began filtering up into his father’s dentist’s office. His father stomped his feet on the floor and yelled down to the boys.

“I’ll never forget what he said,” John said. “‘What the hell are you guys doing down there?'”

But John persisted with his hobby, learning as much as he could and experimenting along the way. He, like his father, became a dentist, and, after 4 1/2 years in the Army Dental Corps in Europe, he has practiced in Craig since 1971.

John said that his career funds his hobby, and that he has no intention of retiring anytime soon. He now donates his time and supplies to put on fireworks shows in the area, which run about $8,000 a piece.

“Most of my interests were in pyrotechnics,” he said. “It was something I never grew out of.”

And it’s something his son hasn’t either. Now 20, Johnny shares his father’s passion for explosives. He’s home for the summer, in between semesters at Colorado Northwestern Community College and the University of Wyoming, where he intends to study to become an agricultural veterinarian.

John’s daughter, Rachel Veenstra, helps out with shows on occasion, but she doesn’t like the hundreds of hours of preparation that go into putting one on. Like her mother, Veenstra likes to stay on the sidelines and watch.

But John already has big plans for his grandson, Keegan. He is just 4 1/2 months old, but he already has a “future pyro” jacket. For now though, it’s just a two-generation hobby until Keegan is old enough to participate.

“He’s basically the professor, and I’m the lab rat,” Johnny said about he and his father’s experimentation. “He’ll think up the idea, and I say, ‘Yeah, I’ll do it.'”

He has nearly free reign to try new stunts at the Pyrotechnics Guild International annual conventions, which the whole family attends. Everyone can take classes about various types of fireworks, and then show off their skills to other pyrotechnics.

And although safety is a priority, sometimes fireworks do not function properly, or the technicians get a bit overzealous.

“It just happens,” Johhny said about a circular scar on his back from a homemade device. “You play with fire, you’re going to get burned.”

Father and son have picked up an interest in machine guns and muscle cars, as well. But it seems that their true passion still lies in the world of pyrotechnics. And that’s where the men intend for it to stay.

“Once you smell the smoke,” John said, putting his nose to the end of a recently-fired mortar, “you’ll never go back.”

For more information about pyrotechnic devices or the international organization, visit http://www.pgi.org.