Volunteer Ryan Perry said, "The fact that he's working with gunpowder... It's explosive material. You don't ever know what it's going to do."
Cai says he's used gunpowder to create art since the 1980s. Most recently he's known for making the opening ceremony fireworks for the Beijing Olympics in 2008. You can see in some of his other works how at the very end of the process, he ignites the gunpowder in a controlled explosion which creates unique patterns.
"It's visceral. It's powerful," said Christine Starkman with the Museum of Fine Arts, Houston. "The sound, the smell, the spark -- you're part of it. You're part of the creation of energy."
The Museum of Fine Arts, Houston has commissioned Cai to create a permanent exhibit for its Arts of China gallery which opens later this month. The 42 panels will line the walls, totaling 10 by 162 feet, surrounding other artwork on display. It will be one of Cai's largest works ever.
Cai uses 15 varieties of gunpowder, each with its own unique property and ability to create varying levels of explosions and intensities of color. He likens the process to the growth of a successful relationship.
He said, "There's a passion, uneasiness and a strong desire. And you also have to have courage."
With that courage he finds faith that what he's building here will be good. But he says again, like a relationship you won't know exactly what you're getting to you see the sparks fly.
About 100 volunteers helped make this project over the last three days. It will be permanently housed in the Museum of Fine Arts.