Kimberly Smith, a senior at Stone Memorial High School, used her engineering skills to solve a common high school problem: students toying with gas valves in chemistry classrooms.

The project not only earned her high marks in her engineering class but also took first place in the Oak Ridge Institute for Science and Education November 3D Printer Design Challenge.

“We wanted something small and compact that would be easier to remove and deal with,” Smith said of her design. 

SMHS had a minor gas leak in the chemistry lab early in the school year. The student gas valves are controlled by a master valve, which developed a small leak. Though the problem was quickly identified and corrected, with no danger to students or staff, chemistry teacher Marcela St. Onge asked engineering teacher Tommy Tatum to help design a lock that could prevent those student valves from being turned on. 

Tatum said, “I said I had the team for her.”

He assigned his Engineering 4 class to the project. The students worked as a design team.

“They interviewed the client and had them all create a solution. Even as a team, they each came up with their own ideas,” Tatum said. “We submitted those to the client, and she chose the one she liked.”

Smith said the first step was to research products already on the market that addressed the problem. They found three such designs but those were designed for more industrial settings and not school chemistry labs. 

The team needed a simple, effective and reusable design that would also be cheap to make. St. Onge requested the final design be made strong enough to withstand students trying to remove or break them but also sleek to retain access to electrical plugs. It needed to hold the knob of the gas valve perpendicular to keep it in the off position and while not required, a universal design to fight either right or left nozzles was wanted. 

Smith began with a wedge that would pop onto the handle and the nozzle. That didn’t meet all the criteria, however. She changed the idea to a wedge that would encase the handle and work as a locking hinge. It could be used on either side.  

“I made multiple designs and tested each one,” Smith said. 

The first design didn’t work because the top holes were too short for the handle. Smith refined the design, with larger slots for the handle and a place to use a zip tie to secure the lock. 

A fourth design further refined the design, offering a snugger fit on the nozzle and handle. The fifth design brought everything together with a sturdy product that met the project objectives. 

3D printing provided an easy way to produce the locks, test their performance and make any necessary changes, though printing times ranged from 2 1/2 hours to more than 8 hours. 

Smith learned about the Oak Ridge competition and submitted her work, winning first place in the high school category. She was awarded a laptop, a 3D printer and filament. 

Tatum said, “My ultimate goal is to foster creativity and create problem solvers.”

He introduces students to design and teaches them to create designs and test their design performance. Students are first taught to use an open-source design program, Sketch Up. Then Tatum introduces the industry standard program, Solidworks. He’s working on getting his certification in the program and will then be able to certify students. 

Smith began studying engineering her freshman year. She enjoyed it and signed up for more classes. 

“I’ve always found it fun,” she said. “You’re always trying to improve on what you’ve done before…You try to be the best you can be with it.”

Tatum said Smith is a well-rounded student.

“That’s ideal for an engineer,” Tatum said. “I’ve been pushing her to go into engineering. She’s hands-on and can put things together and then sit down and work out the math.

“We’re super proud of her and can’t wait to see what she does in the next five years.”

Smith plans to attend the University of Tennessee next fall and major in engineering. She’s still exploring options available in areas of mechanical, biomedical or nuclear engineering. 

Her father has rheumatoid arthritis, an incurable autoimmune disease that attacks joints. She has an interest in research in ways engineering could make life easier for individuals with rheumatoid arthritis. 

Heather Mullinix is editor of the Crossville Chronicle. She covers schools and education in Cumberland County. She may be reached at