Student develops playable acoustic guitar from the 3D printer

At Binghamton University, mechanical engineering student Timothy Tran has designed an acoustic guitar whose body is produced entirely by 3D printing. Instead of wood, he uses thermoplastic filament, while the strings and tuning machines are the same as on a conventional instrument. The starting point was his father’s damaged guitar, which could no longer be repaired.

“It wasn’t something that people had really looked into,” Tran said. “People have made 3D-printed electric guitars – that’s probably easier because you don’t have to worry about the vibrations as much. I just wanted to try something new.”

“I just kind of pointed in the right direction and gave him some guidance,” William E. Schiesser, a lecturer at the School of Computing, said. “We’ve met every week since the beginning of the summer, and he’s really done some great work with us.”

First he spent several weeks measuring the old guitar and transferring the geometry into Fusion 360. Crucial factors were the exact positions of the neck, bridge and sound hole so that scale length and intonation would remain within acceptable limits.

Printing was done on a Prusa MK4 FDM printer with a build volume of around 25 centimeters. Tran had to segment larger structures such as the top and sides; even the fingerboard consists of two parts. The segments are joined using interference fits and a specially designed connector plate, and then glued together.

“Putting it together was pretty easy. It only took one or two days. It was more just waiting for the glue to dry,” Tran said. “The longest part was probably just waiting for parts to print. Bigger pieces might take six or seven hours to print.”

“I’m just trying to figure out a way to make the neck piece a little more uniform, and how to get the action lower,” Tran said. “Just to get it to a more playable feel, because right now this is pretty tough to play. It doesn’t feel that comfortable.”

“It’s an iterative process. You make one prototype, see how it works, then correct any issues,” Schiesser added.

The prototype is already playable, for example for simple classical pieces or rock riffs, but it does not yet match the comfort of a production guitar. The action is too high, and the instrument is also difficult to tune accurately.

“Once I finished it, I gave it to him first, and he was overjoyed to play it; he texted all his siblings bragging about it!” Tran said.

“If it were to become something really successful, I want it to be just something that can be free access for everyone,” Tran said. “Growing up, we didn’t have that much money … so if it’s just something that’s easy and accessible for people who need it, I think that’d be really cool.”

In the medium term, Tran and Schiesser want to publish the CAD model as a freely accessible design. The estimated material costs are 25 to 30 US dollars, including filament, strings and tuning machines.

“Just like we share software and code by open source with license, this could be posted online, and anybody could access the design for free, as long as they have access to a 3D printer and can get it printed out,” Schiesser said.

“It was good to put out into the world,” Tran said. “It’s just a good way to direct what I wanted to do, because I had a lot of ideas, but I didn’t really know how to employ them. It was just really cool to see an idea I had just really come to life.”

For users with access to an FDM printer, the approach could offer a low-cost way to build their own instrument – and at the same time shows how 3D printing is extending traditional craft domains such as instrument making.