If you#re The Boeing Company, trying to build a plane to exact specifications, a thick layer of paint can be a big pain in the neck.

Due to detailed specifications, a few extra paint strokes can cause the weight of a component to exceed its weight limit, which means workers have to dismantle the components, remove the paint, and redo it. The process takes days of extra work, costing the company plenty of time and money. Furthermore, dismantling components from the completed plane also creates the potential for breaking expensive parts.

Currently, there is not an effective method of measuring very thin layers of paint on composite materials used in modern airplanes.

Undaunted, four Washington State University students tackled the paint issue head on and came up with two methods for measuring the exact thickness of a coat of paint, which is generating a lot of excitement at The Boeing Company.

Extra paint, causing a component to exceed its weight limits, “happens often enough that it has been identified as a problem that needs to be taken care of,” said Edward Sergoyan, a lead engineer for Boeing.

Working with Bob Olsen, professor in the School of Electrical Engineering and Computer Science, Sergoyan suggested that students do a feasibility study to figure out potential solutions as part of a senior design project.

Working on the yearlong project, students came up with two “very clever” potential approaches, said Sergoyan.

“The new techniques look very promising,” he said. “I was surprised by the thoroughness of the investigation and very surprised by the good test results. It has great potential.”

In the first technique, called the resonance method, the students inject a small microwave signal into a box with an open side. The changes that occur when the open side came into contact with the paint determine the paint thickness. In the second technique, called the capacitance method, students put two electrodes on top of the paint and connected a voltage between them. An electric current is created, and the students determined that the impedance, or how much current can’t get through, depends on the thickness of the paint. The system they devised would not require taking apart the plane to measure paint thickness. Instead, the system could be used directly on the aircraft after assembly.

The students spent the year designing their methods and proving that they work. Boeing sent them painted samples and provided guidance along the way.

“Compared to repainting and taking the plane apart, this is dirt cheap,” said Olsen, the students’ adviser. “These students were innovative, and they worked well together. They were tenacious.”

Students on the project included Corbin Champion, Kirk Jackson, Mohamed Moalim, and Hiep Tran.

“It was really satisfying to work on something that is going to have a real value to someone,” said Jackson.

Boeing is evaluating their reports and the test data. They will then see if it is appropriate to build a prototype tool. And that may be a project for next year#s senior designers, said Sergoyan.