How Do Fireworks Work?
MINNEAPOLIS (WCCO) - It's still 34 hours before the Lakeville's Fourth of July show, but the RESPYRO crew is setting up 700 tubes that will hold fireworks for the 20-minute show.
"We can shoot in a downpour if we have to," says RESPYRO CEO Steve Coman. "It's all waterproof, make for outdoor weather use."
But Coman would prefer not to have it rain. He will be the one behind the computer hundreds of yards back when the show runs Wednesday night. It has been 15 years since anyone in his company used fireworks that were hand-fired.
On Tuesday, Coman showed WCCO the inside of a firework, or single aerial shell, as he calls it.
Inside is a black powder charge that will light when it is ignited from an electrical igniter that is hooked up to the bottom of the firework.
That powder then connects to a timer fuse, which once is goes off, will propel the shell into the air.
Once the spark makes it up the fuse -- when the shell is in the air -- the powder inside the shell will burst, sending the "stars" into the sky. It is the stars, which are little pieces of chemical composition that burn different colors, that people see in the air.
In the fireworks that look like smiley faces or hearts, the stars are lined up inside the shell in those shapes.
Coman says it takes an hour to choreograph one minute of a show, and another six to seven hours to set up and a few more to put in the fireworks.
"Every show is different," he said. "There's no one-size-fits-all."