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When a Cub Scout builds a pinewood derby car, he tends to focus first on what the racer will look like when it rolls across the finish line.

When engineers build a Pinewood Derby car — they’ll do it if you ask them nicely — they tend to focus first on taming the Newtonian forces that keep it from crossing the finish line even faster.

The cars might not be pretty, but they’ll roll like thunder.

For The Dispatch’s first-ever derby competition, two graduate engineering students at the Ohio State University Center for Automotive Research followed the speed-first-looks-second formula.

The OSU car was a thin piece of unpainted wood with a stack of metal weights screwed on top.

The car defeated cars submitted by Battelle; Edison Welding Institute, a nonprofit developer of manufacturing technologies; and 10-year-old Kyle Juracich, a Cub Scout and derby veteran.

“We tried to simplify it as much as possible,” said Mark Hornak, a material science engineering student at OSU’s Center for Automotive Research.

All of the teams took the challenge seriously. How seriously?

Battelle and Edison Welding set up their own test tracks.

“Theory can only take you so far. You have to test and do iterations,” said Jerry Durham, a Battelle research scientist. “We probably had eight or nine designs before we got to an optimal solution.”

That is only a little glimpse into that team’s quest for perfection. Battelle also analyzed each block of pine and discovered that their weight differed depending on which part of the tree the blocks were cut from.

A difference of just a few hundredths of an ounce would affect performance, said Trey Musgrove, a Battelle mechanical designer.

For the most part, however, friction is the foe that these teams concentrated on for both the regulation cars they made as well as the “cheater” cars that allowed them to design racers outside the shackles of Cub Scout rules.

While gravity is the force that propels your car, friction is the force that drags, grinds, slows and stops it in its tracks.

Victory in a pinewood derby goes to the car that lessens that friction by achieving the best combination of weight, axle load and aerodynamics.

Although the derbies didn’t start out as scientific endeavors, that idea now fits into the the push toward the Science, Technology, Engineering and Math (STEM) Initiative, which encourages children to study and eventually take jobs in those fields, said Jeff Moe, CEO of the Boy Scouts of America’s Simon Kenton Council.

Thousands of websites offer physics lectures, videos, design tips and how-to books on Derby cars. And many of them focus on where the weight should be placed on a car that cannot exceed 5 ounces.

“Bottom line: Centering the weight of your car as much as possible toward the bottom, back corner of your car will make it faster during the race,” according to a lecture posted on a Stanford University website.

Not so fast, said David Walters, a design engineer on Battelle’s team.

“You could pop a wheelie,” Walters said. “You want to get (the weight) within an inch to half an inch around the rear axle. That seems to be the sweet spot.”

Walters said the height of the weight should increase the car’s potential energy when it was placed against the track’s starting post.

Balance is everything, said Giorgio Rizzoni, who directs the OSU Center for Automotive Research and is a veteran of several derbies with his sons.

“You want to have it well-balanced,” he said. “You want to have as little friction as possible"

Rizzoni, who has written physics lectures on the subject of pinewood cars, said he prefers to distribute the weight near both axles.

The weight of the car itself can slow it down.

The OSU team designed its cheater car to “shed” weight at the right moment. The idea was that the weight that helps a car gain speed on the incline also slows it down the straightaway.

So the students fitted the car with a large metal weight that rolled off the back when it reached the straightaway.

The Edison Welding team’s cheater car used a wild design to battle that problem.

Its car was a two-stage vehicle that increased potential energy at the top of the track and launched a smaller, lighter car from a ramp toward the straightaway.

Another speed-killer is axle friction.

The OSU team said it battled that demon by sanding the axles using four grades of sandpaper.

Then the team treated the axles with a rubbing compound and a polish.

“They had a mirror finish,” said Matt Organiscak, a mechanical engineering student.

Organiscak said the spaces between the wheels and the axles were then packed with a graphite powder lubricant that is allowed in derby races.

Cub Scout Kyle Juracich said he and his father, Jon, also spent considerable time sanding and lubricating the axles. Their cars placed second in both races.

Durham said a lot has changed since he designed his first pinewood car when he was a Scout.

“I was trying to make it look cool.”