Sophomore Tommy Bond’s response to a high school assignment could prove valuable in his future career as a band director: He printed a low-cost replacement part for his sousaphone.
William Blount High School teacher Randy Craig challenged students in his Principles of Engineering and Technology class to develop an invention that would benefit others or an innovation.
Their responses ranged from fishing lures to a flying ambulance.
Tommy is taking the class because it fit an open spot in his schedule, but his primary interest is music education. After his group completed a plane design, Tommy connected the assignment to his interest in music.
A classmate recently had forgotten a mouthpiece to an instrument, and at a cost of around $100 Tommy knew it isn’t practical for most students to keep a spare handy.
“I thought it would be interesting to try,” he said of his decision to create a new mouthpiece.
Using Tinkercad digital design software on his school-issued Chromebook computer, Tommy designed a new mouthpiece for the sousaphone he plays. Then he printed it on the school’s Printrbot 3D printer at an estimated cost of less than $5 for the filament the printer uses to create the object.
The Printrbot takes about five hours to make a solid object from the computer-aided design.
“It leaves some rough edges, so you have to sand it or melt it,” Tommy explained of the item that comes out of the printer.
With no precise way to measure some parts of the original metal mouthpiece, such as the depth of the mouth cup, Tommy’s third prototype was the first to fit well, without a large gap. He further refined his design and used a different type of filament for the fourth attempt.
“It’s definitely different, but it’s not bad,” he said of the sound the sousaphone makes with the printed mouthpiece.
Tommy already has ideas for other parts to print. During a parade in Gatlinburg last week, a button from one of the tops of his valves came off while William Blount’s band was marching, and other parts called bits tend to wear out or become stuck.
The printed mouthpiece had one advantage over the metal model, in addition to cost. It doesn’t get as cold, Tommy said.