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CNC Machining Magazine | ||||||||||||
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Every spring, engineering students from universities around the globe descend upon the Detroit area to participate in the Formula SAE Collegiate Design Series competition. Put on by the Society of Automotive Engineers, FSAE is the culmination of a year-long program in which students conceive, design and fabricate a formula-style racecar. The completed racecars compete in static and dynamic events, such as technical inspection, cost, presentation, performance trials and high-performance track endurance. This year, a record number of teams – nearly 2000 students – participated in the event. One of those teams was Matador Motorsports. Like every student racing team, Matador is made up of highly enthusiastic engineers-to-be who put in workaholic hours to build a car that will outperform the competition’s. Unlike the average student team, however, Matador has finished in the top 11% in more than a third of the Formula SAE races in which they have competed. Matador hails from California State University at Northridge (CSUN) and, except for a break during the years 2001-2002, has been competing since 1995. The 2004 team finished in the top 10% this past May.
In 2003, Matador’s team placed an impressive 10th overall out of 140 entries, landing them in the top 7%. They didn’t revel in their success for long, however. With the school year ending immediately after the race, Matador set about assembling a new team for the 2004 competition. Tin Bui, now a graduate student, worked on the engine of the 2003 car and then became the 2004 Project Manager. Aspirations were high for the coming year. “Our tenth-place finish really had the new team motivated to beat that placing,” said Tin. Heading into summer, the team had a lengthy to-do list, which included reading all the documentation on and then repairing the 2000 racecar (the last car CSUN built before the ’03 one). This introduced new team members to the principles of racecar design. Once they had the fundamentals down, they turned their attention to redesigning the ’03 car for 2004. “The plan,” explained Tin, “was to model a new, unrestricted intake system and new engine cover, and adapt it to the 2003 car’s fuel injection system.” One Saturday there was a huge turnout in the lab to build the new components. “Our momentum was at its peak,” Tin said. Unfortunately, “the momentum abruptly died when the 2003 car came back in pieces after an accident.” Needless to say, seeing the team’s best-placing car reduced to a pile of damaged parts was quite a shock. Not much got done that summer. But by the time the new school year started, Matador had regrouped. Given the time they had lost, Tin felt the team “needed a conservative design goal. I wanted an evolution of the 2003 car . . . just optimizing the current designs would reduce the time needed to remodel everything.” Other students on the 15-member 2004 FSAE team had different ideas. “They wanted more drastic changes,” noted Tin, “and they understood what needed to be improved.” In the end, the only components that didn’t undergo a design change were the driveshafts, stub axles, jack shafts, hubs, spindles and body. The rest of the car saw major modifications. The biggest change was replacing the rear chassis with an aluminum monocoque, using the engine and drivetrain housing as a stressed member. The chassis size was greatly reduced, so “the suspension was redesigned to have a smaller track and wheelbase, and also different packaging constraints,” Tin reported.
The team began manufacturing parts during the fall semester. CSUN happens to be Gene Haas’ alma mater, and back in ’98 he entrusted a couple of Haas CNC machines to the school’s College of Engineering and Computer Science. The Gene Haas Engineering Lab has an HL-2 lathe and a VF-2 vertical machining center (with plans to add both a Toolroom Mill and Toolroom Lathe in the coming year). Professor Stewart Prince is the lab administrator. “We have the latest and greatest machines in our lab,” noted Dr. Prince, “and the machines are so user-friendly now that we can take a mechanical engineering student who knows nothing about machining – but lots about machine design – and have him or her design parts using CAD, and of course use the analysis tools, and go straight from there to CAM and generate the G code. “I give them an introduction to the CNC machines: ‘Here’s the machine, here’s how the control works, don’t drill any holes in the table. When it’s time to run your part, come and get me.’ Then I run it in Graphics to make sure it’s going to work right, and if it does, then off they go. “That’s how we can take students who have no machining experience and make an entire Formula car, where 90% of the parts are made on Haas CNC machines,” he said.
Now, while that’s the condensed version of how CSUN students learn to run Haas machines, it’s really not that far off. Jason Frick is a graduate student who was this year’s chief drivetrain engineer. “I just kind of dove in,” he said. “This project forces you to get things done! During 2002-2003 we didn’t have anybody with any manufacturing experience. So John Mason [another drivetrain engineer, who designed the rear monocoque] learned to weld, and he became our welder. Well, I stood next to Dr. Prince and learned the controller on the Haas machine, and I already had some experience with CAM, so I became the CNC machinist. I did all the parts for our 2003 car, and then this year I had help.” Mike Stackhouse, Matador’s 2004 chief chassis engineer, had been machine shop supervisor at Edwards Air Force Base. Mike was at Officer Training School at press time, and hence unavailable for comment, but “He had good things to say about the Haas machines,” according to Jason. “He loved that Quick Code stuff.” “And,” added Tin, “Mike knew what type of tools to use, the speeds and feeds, all that stuff.” Needless to say, Mike’s skills and experience were a very welcome addition to the team’s knowledge base. Jason and Mike machined “all kinds of aluminum – 7075, 6061, 2024 – and a lot of steel, too. A lot of alloys – 4130, 4340, some mild steel,” Tin continued. “Some of our competitors buy their parts. But we design everything for our application, which makes our car much lighter and faster than most of our competitors’ cars. And we have higher build quality, and more accurate parts that we can trust. There are a lot of high-tolerance parts, especially in the drivetrain and the suspension.” Another recurring theme among Matador’s student engineers is the quality of this educational experience. “You’re not given these kinds of skills in a classroom,” noted suspension engineer Katrina Finley. “The Formula racecar project is one of the most prestigious ones; it’s just got a great reputation within the Engineering building. It gives you a lot more hands-on experience than most of the other design projects.” Jason concurred: “I’ve learned more in the last two years, just from this project, than I have from my classes.”
It’s a phenomenal amount of work, but Matador team members are – as the saying goes – in it for love, not money. “We’re the ones who are in the lab on Friday nights,” Katrina said, laughing. “We’re there early in the morning, late at night – it takes a lot of motivation. You really have to have a heart for it.” In Jason’s estimation, “Those of us who spent the most time on the project were here in the lab probably 50 to 60 hours a week. That’s not including our other classes.” The result is a racecar with impressive specs. “We have a really good engine development program at CSUN,” Tin reported, “so we have a massive amount of horsepower. It’s fun!” With a wet weight of 467 pounds, length just under 104 inches, and a 64.5-inch wheelbase, the car generates 85.2 bhp, for a 0-to-60 time of 3.7 seconds, a top speed of 102 mph, and an FSAE Skidpad Event tally of 1.25 g of lateral force. Out of 140 FSAE entries this past May, Matador placed 8th in the Acceleration Event, 9th in the Autocross, 14th in the Skidpad Event (as well as 14th overall), and took the 3rd place Powertrain Award. “This is racing,” said a philosophical Tin, “where everyone is disappointed except the winner! We’re in the top 10% worldwide, and we know that CSUN is a contender to win.”
Even more important, though, is that a project like the FSAE car not only makes engineers out of the students who work on it – it can also inspire students who don’t know yet that they like engineering. Katrina, the only woman on this year’s CSUN team, hadn’t planned on an engineering major when she started college. As a small girl with three brothers, she “wasn’t really into Barbie dolls – I was into putting train sets together and getting my hands dirty and stealing my brothers’ toys.” Although she continued taking more advanced math and science classes as her education progressed, “I thought I’d be a cinematographer, or an English major. Then I heard about engineering from my classmates. So I started looking into it, and found out engineering is not just textbooks and formulas. You have to have an imagination and creativity. I have an affinity for art and for science, and how they combine – and I get to use both skills as an engineer.” Which is really the point of getting an education: finding a career where you enjoy what you have to do every day. Now that’s the hallmark of a winner. ~~
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