An object that dries too slowly can cave, he explains. A breeze or jolt can leave a project misshapen.
Of course, the potential for errors — and the ability to correct them with mechanical enhancements and software tweaks — also makes the printers a tinkerer's dream. Both Ta and Reese spend hours programming and adjusting the printers to improve results.
Reese, who has seven 3-D printers in his Glen Burnie home, including some he has built himself, has always been fascinated with building things and experimenting with technology.
"My whole childhood was Legos," he says.
Ta took a different route to 3-D printing. After graduating from University of Maryland, College Park in 2010 with a degree in finance and economics, he briefly worked in finance before losing his job as a result of the tough economy. A few months later, he was thumbing through an issue of Popular Science in his parents' Gaithersburg barbershop when he came across an ad for an affordable 3-D printer. He ordered it on a whim and quickly became fascinated by the technology.
Now Ta, 25, runs the Digital Fabrication studio at Maryland Institute College of Art, where he guides students through the use of 3-D printers, 3-D scanners and laser cutters, among other technologies.
Ta, who lives in Hampden, hatched the idea of bringing the printers into the bookstore.
"I was thinking, 'How do we get this out there in Baltimore?'" says Ta. "It's a novel, fun way to get exposed to it."
Ta would like to see 3-D printing, and similar technologies, lead a manufacturing renaissance in Baltimore. He slaps "Made in Baltimore" stickers on his creations, hoping to spark conversations about the city's creative power. He points out that the banks of the nearby Jones Falls were once lined with mills.
Rachel Whang, co-owner of Atomic Books, thought the shop's customers would be interested in experimenting with the technology, especially watching the creation of a plastic bust.
"Seeing you printed in front of you — it's like the first time you saw a flatbed scanner or a Xerox machine," said Whang.
Customers are already compiling lists of items they would like to print.
Noel Conrad, owner of Novelty Haus, a store about a block north from Atomic Books on Falls Road, brainstorms items he would like to print while waiting to be scanned for his bust.
Conrad, 31, wants to make joints for the small toys that he sculpts. But he has more ambitious plans for the future.
"I'd like to get some organs printed out for when mine start failing," he says.
If you go
The 3-D printing studio will be open the second Sunday of each month at Atomic Books, 3620 Falls Road. Busts range from $20 to $75, depending on the size. For more information, email Andy Ta, email@example.com.
A previous version of this story provided an incorrect price range for the busts and erroneously referred to Andy Ta's role at Atomic Books.