The Utah branch of the legion, known as Alpine Garrison, was created in 2002 and makes appearances regularly.
Reactions vary when the Dark Lord of the Sith shows up in random places. Hales has experienced everything from ecstatic fans to those who are completely bored with him.
"I have had people throw rocks at me," Hales said. "I have been punched so many times by kids who come out of nowhere."
So he installed a protective piece of leather to his lower half and has spotters protect what he can't see in the low-visibility suit.
"My wife [who is also in costume] has been really good at keeping kids away who charge at me."
Making the costume was no simple task.
"It is not one of those things that is commercially available," Hales said, adding he had to assemble each piece by purchasing expensive parts through different vendors around the world.
He did all his purchases through the Internet and found a man in Argentina who made him a custom-fitted leather suit with mesh in the back for maximum breathability. He also wears multimedia parts.
"I connect an MP3 player to my belt that runs a cycle of Vader breathing [sounds], and in the chest box I have an electronic light board," he said. "That really is the thing that completes the costume."
As a trained actor, Hales said he prefers to just lower his voice to sound like Vader, rather than buying a voice modulator box.
Hales said a distinct Darth Vader suit was made for each of the four films. All had something a little different, and all but the final one were handmade.
"I went for the 'Episode III: The Revenge of the Sith' version," he said. "I consider it to be a more intimidating mask. It was the newest one and I liked the color scheme."
Becoming one of the 501st Legion's 8,000-plus worldwide members isn't easy. Members' costumes must be legitimate and authentic.
Potential members must make their costumes and submit them to the legion for review and approval, Hales explained.
Mark Fordham, of Provo, wears a Darth Vader costume as well and was the president of the international organization from 2006 to 2009. During that time he traveled to California on his own dime to meet a Lucasfilm Ltd. liaison on behalf of the 501st. An agreement was made with Lucasfilm Ltd. so fans could create costumes and not violate intellectual property rights.
"That face time really made a difference in our relationship," Fordham said. While the 501st is not sponsored by Lucasfilm Ltd., it is the "preferred Imperial costuming group."
The reward for members is seeing reactions from Star Wars fans.
"This is not someone in just a cheap Vader costumer," Hales said. "[Fans] respond to you like you are a real person. Everyone wants to touch the buttons, and it is almost like they think there is something magical in there that is going to happen."
One time Hales was asked to make an appearance at Primary Children's Medical Center for a 7-year-old boy with pancreatic cancer. "I suited up and visited him," he said. "I visited the entire floor of kids. A lot of them were connected to feeding bags and made it out to come see me. It was really rewarding to see that magic light up in their eyes."
He said seeing the crowd of excited children coming out to get photos brought tears to his eyes. But the actor added: "I had the mask on, so I was still in character."
Twitter: @CimCity Learn more about Star Wars fan clubs:
Alpine Garrison • www.alpinegarrison.com
The 501st Legion • www.501st.com