One inch steel tubes were welded together over winter break to form a race car chassis as Cal State Fullerton engineering students toil to build a race car to compete in the annual Formula Society of Automotive Engineers (FSAE) competition.
By May, the Yamaha R6 powered senior project, built to FSAE’s race car specifications, will be ready to race.
The steel tubular space-frame chassis was finished on Jan. 26, according to CSUF FSAE team director Fred Hogarth.
“During break I saw footage of other teams chassis completed … They finished by mid-January. We finished by late January.” He said he believes CSUF’s car is about even in the build phase with cars from other university FSAE teams.
“The hardest part was designing (the chassis) to meet everybody else’s needs,” chassis designer Jason Gardiner said.
He explained that mounting points for the suspension, powertrain and other parts had to be taken into account and implemented during the design phase.
“The suspension was the most critical,” Gardiner said.
The team tack-welded the chassis together in room E-21 of the College of Engineering and Computer Science, but left the stronger, more complicated seam-welding to students of Fullerton College’s welding certification program, Hogarth said.
“These guys are trained to be professional welders as a career. They can weld better than us, faster than us, more efficiently than us — with stronger welds. We trust them to fully weld our chassis,” he said.
Various car parts line the outer counter: A front differential with axles from a Polaris 500 four-wheel-drive ATV, wheel hubs from the front suspension of a Geo Metro, a custom machined front hub with attached brake disk from last year’s car.
“The biggest problem is money. People are happy to work with us, happy to work for us, they won’t just give us their metal,” Hogarth said. That is why the team tries to use parts from other vehicles, hence the Polaris differential and the front hubs from a Metro. For this year’s car, the front hub assembly with brake disks will again be custom machined and Hogarth said each side will cost about $1000.
When asked to explain the cost advantage to using the Polaris differential, obtained for $125, Hogarth said, “It saves time and money. All the R&D has been done for us by Polaris, so all we have to do is buy their part. … It would probably cost us between six to 10 thousand (a) machine,” if they had to have a machine shop do it. “The gears are really hard metal, so it’s expensive to chop all the gear teeth.”
Last week’s project for the suspension team was to start making the control arms out of 3/4 inch hollow steel tubing. Control arms are attached between the wheels and the chassis and allow movement between the two, regulated by shocks and springs. The shocks and springs are inboard on CSUF’s car, suspension team leader, Paul Nordeen, said, because the race car will be graded and judged on innovative design. He also said that maintenance is easier with the inboard design.
More than anything, it’s crucial for the car to have a well-made and well-tuned suspension, able to soak up bumps and endow the car with neutral at-the-limit handling characteristics.
Nordeen said the lower control arms are finished, but the more complicated upper control arms are taking more time.
“We are going to be hopefully finishing the upper arms this week,” he said.
The suspension team will also be drilling and tapping mounting holes on the chassis, where the spherical bearing rod ends of each control arm will be anchored, Nordeen said.
The machine shop on campus, sporting new machines, still receives little use, as the search for a replacement machinist was recently approved by the university. In the meantime, engineering students, such as those on the FSAE team, must outsource machine work at a greater cost.
“The labor is cheap. A lot of the labor we can do ourselves,” Hogarth said.