To bolster their claim, the company is pulling a curious stunt here at the 2015 North American International Auto Show: It's building what it calls a “micro-factory,” consisting of a large 3-D printer and CNC machine, on the showroom floor to piece together an electric vehicle in front of attendees. The process began on Monday and the car should be finished by the end of the week. Once it's a wrap, attendees will be able to test-drive the machine on a closed track.

“We make our cars in a three-part process, and one of the exciting things about it is the speed to which we can bring manufacturing of vehicles to reality,” said John Rogers, Jr., co-founder and CEO of Local Motors, during a press conference at the show.

The vehicle being printed at the Detroit auto show, which opens to the public on Saturday, Jan. 17, is an updated version of Local Motors' low-speed electric vehicle. The model's name is the Strati, which means “layers” in Italian, and refers to the 3-D–printing process where successive layers of material are laid down under computer control—in this case, carbon-fiber-reinforced thermoplastic. The new car is a redesign of Local's original vehicle with subtle changes, consisting of different headlight housings and other tweaks to give it a more sophisticated, polished look.

"We think it's pretty fun to think about a mid-model refresh often happening two to three years into the cycle of a car," Rogers says, "but now it's happening two to three months into a cycle of a car."

Local Motors also announced that it's opening two new micro-factories: one at National Harbor, Maryland (just outside of Washington D.C.), and another in Knoxville, Tenn., to be operated in conjunction with Oak Ridge National Laboratory (the largest science and energy laboratory in the U.S.).

“We like to think about it as Build-a-Bear mashed up with Ikea mashed up with with Formula One."

Today only one micro-factory exists at Local Motors' headquarters in Phoenix, Ariz. The new National Harbor factory could be the first ever to manufacture and sell 3-D–printed cars. The company said it will break ground this fall and start filling orders shortly thereafter.

A Local Motors micro-factory is about 40,000 square-feet, which is a fraction of the size of an automotive manufacturing facility. It includes a laboratory, a build floor for light assembly of vehicles and other products, and a showroom and retail store.

“We like to think about it as Build-a-Bear mashed up with Ikea mashed up with with Formula One,” Rogers says. The long-term goal is to locate all micro-factories within 100 miles of major urban centers, create local jobs there, and reduce auto freight and distribution costs by 97 percent.

Currently, the Strati takes about 44 hours and 212 layers to fully print. Only the body structure of the vehicle is actually made through 3-D printing; the electric drivetrain (sourced from Renault/Nissan), seats, gauges, wiring, and tires are added to the body after it's printed and milled. Rogers told Popular Science he expects to reduce the print time down to 12 hours through coming efficiencies in 3-D printing technology and software.

The Strati will cost between $18,000 and $30,000 when it goes on sale in 12 to 18 months. Initially, it will be classified as a neighborhood electric vehicle, or NEV, limited to driving on roads with posted speed limits of 45 miles per hour or less.

Local Motors is seeking approval from the National Highway Traffic Safety Administration for highway-capable vehicles, a process that is both time- and resource-intensive.