Q. Please briefly introduce yourself and your team.
A. Hello, I am Kim Dohyun, the Powertrain Section Lead for TEAM NSSUR. I am currently a senior (3rd year) and was responsible for designing the intake system. TEAM NSSUR is an official central club at TECH UNIVERSITY OF KOREA founded in 2015 by CEO Lee Jun-myung of Neotech. The team name, NSSUR, originates from Neotech’s suspension product line.
We are a club that engages in automotive-related activities and builds formula and autonomous racing cars to compete in competitions. We have previously achieved excellent results by competing in the off-road Baja vehicle and electric EV vehicle categories, and since 2024, we have been competing in the C-Formula (internal combustion engine) category of the Formula division. For this year’s car, we are using KTM’s 690 SMC-R LC4 engine and adopted Lincsolution’s technology to maximize the engine’s performance.
Q. Why did you choose the MJF method among various 3D printing technologies?
A. We determined that the geometry we designed was quite difficult to machine using CNC or general machine tools, so we decided to manufacture it using 3D printing.
In particular, the intake system we designed has to withstand high-temperature and high-pressure environments, making heat resistance, strength, and rigidity crucial. Considering these conditions, we determined that Lincsolution’s MJF process was the most suitable among the various 3D printing processes.
Q. Did you run simulations beforehand to see if it could actually withstand the operational conditions?
A. Yes. When designing, going through physical manufacturing repeatedly consumes a lot of time and money. Therefore, we utilized CFD (Computational Fluid Dynamics). We first analyzed how much force the air would receive and how much the temperature would rise under actual operating conditions, and then proceeded with the final manufacturing based on those results.
Q. Compared to traditional manufacturing methods, what kind of impact did it have in terms of time and cost?
A. Actually, since this is our first time directly designing and manufacturing a large-scale intake part, a precise comparison is difficult. However, compared to cases from other universities, we were able to manufacture it at a relatively reasonable cost using the MJF process.
The difference was significant in terms of time. Last year, when we printed just the restrictor through another company, we had to schedule about a month. However, when we commissioned Lincsolution, it only took about two weeks from consultation to production. It was a huge help in managing our project schedule.
Q. What was the most satisfying part of your experience using Lincsolution’s service?
A. First of all, communication with the representative was great. They responded kindly even early in the morning and explained things step by step whenever there were parts about 3D printing that we didn’t understand.
When we visited Lincsolution in person, they explained the company and equipment and let us see the actual machinery, which was a fantastic experience.
The delivery schedule was also satisfying. Even though we delivered the final drawings for numerous parts just a day before, the printing was completed right the next day. The working speed was quite impressive.
The quality also exceeded expectations. Looking at reviews from other companies, there were stories that MJF prints did not fit dimensions well, but when we actually inspected the prints, the quality and dimensions came out precisely as I had designed, which was very satisfying.
Q. Why did you choose Lincsolution among the many 3D printing companies?
A. Since it was our first time designing and manufacturing an intake system, we searched through a tremendous amount of data. In particular, professional institutions and companies like the Korea Institute of Industrial Technology (KITECH) and Habistance strongly recommended Lincsolution. Also, while researching, we saw a case where a Genesis GV80 project was printed in a 1:1 scale by Lincsolution, and that technical capability was extremely impressive. Furthermore, the fact that they have many use cases across various industries such as aerospace, robotics, and medical fields, and count several major corporations as clients, influenced our final choice.
Q. Was there anything specific that the representative helped you with technically during communication?
A. For student teams like us, the technology of 3D printing itself is unfamiliar. At first, we thought that if we sent the drawings, they would be printed exactly as designed. However, we didn’t know that shrinkage or compensation was actually necessary during the printing process. The representative explained in detail how much compensation was needed to hit specific dimensions, and that was truly a huge help.
Q. What role does the part you printed play in the vehicle?
A. This printed part consists of a restrictor (air flow limiting device), surge tank, bellmouth, and runners. If we look at the entire assembly as a single unit, it can be described as a space that collects air entering the engine.
The first role is stable air supply. The air passing through the restrictor becomes a very strong turbulent flow, and this is guided into the surge tank to reduce pressure changes. This allows the engine to inhale air more stably during the intake process.
The second is the supercharging effect utilizing pulsation. We designed it to utilize the pressure waves generated while engine valves open and close so that more air can flow in. It is a method of increasing charging efficiency by controlling the timing of air bouncing off the valve and reflecting back inside the surge tank.
Q. How is design know-how like this accumulated?
A. It’s hard to call it a traditional “secret family recipe,” but sometimes excellent reports from teams participating in Formula Student Korea are made public. By referencing those materials, we study how other university teams solved problems.
We also receive and review materials and files designed by seniors. We go through a process of studying why a particular method was used and understanding it.
However, since our team is only in its third year of participating in Formula Student Korea, I think we are still in the stage of accumulating know-how.
Q. I’m curious if participating in competition activities helps with actual employment and career paths.
A. I belong to the Department of Mechanical Engineering, and in the process of designing and manufacturing a vehicle, we actually apply various engineering knowledge such as fluid mechanics, mechanics of materials, dynamics, and statics.
Also, because the process of building a single vehicle itself is a project, we can develop collaboration and problem-solving skills together. In fact, among our seniors, some have advanced into the automotive industry, while others have entered other industries such as semiconductors.
Q. Were there any disappointing aspects or areas needing improvement while using Lincsolution’s service?
A. The print quality and service itself were very satisfying. However, from the perspective of performing CFD analysis, I thought it would be nice if slightly more detailed material property data were provided. Currently, the website provides information limited to tensile strength, tensile modulus, and elongation, but a team like ours also needs data such as Heat Deflection Temperature (HDT) or density. Therefore, if additional property data were provided on the website or if there were links leading directly to official HP data sheets, its usability would increase even further.
Q. How did you learn about MJF technology?
A. We already knew the name to some extent. We also use FDM equipment ourselves, and as you research print quality and material characteristics, you naturally come across various additive manufacturing technologies.
Through that process, we learned about methods like SLS, SLA, and MJF, and when the time came that actual manufacturing was needed, we searched for companies and found Lincsolution.
Q. What kind of regulations are there for the Formula Student Korea competition?
A. There are quite a lot of regulations. First, internal combustion engine vehicles can only use engines of 710cc or less. Also, a restrictor that limits air intake must be used. This is to prevent engines with high output from becoming excessively advantageous. In addition, there are very diverse criteria such as vehicle width, wheelbase, and safety regulations. The rulebook is quite voluminous and managed more strictly than expected.
Q. If your budget allows, would you like to manufacture other parts using 3D printing as well?
A. It is entirely possible. However, parts where strength and rigidity are absolute necessities—such as the frame or suspension—must inevitably use metal. On the other hand, for sensor brackets or components where weight reduction is crucial, I think there are many areas where 3D printing can be utilized. We are actually attempting weight reduction by manufacturing as many eligible parts as possible using 3D printing.
Q. Do you have any memorable episodes while carrying out activities?
A. I remember the time when we poured all our passion into completing the vehicle design and manufacturing within the deadline. In the early days, due to a lack of proficiency in 3D modeling and structural analysis, work was delayed, forcing us to go through grueling campaigns staying up for several nights.
However, without giving up until the end, we relied on each other and solved problems together. Thanks to going through thick and thin together overnight, not only did we drastically improve our design tool utilization skills, but we also gained the true value of collaboration and a tight-knit bond.
Seeing the vehicle we built together after intense deliberation being completed and driving successfully made me realize once again the tenacity toward a goal and the preciousness of teamwork.
Q. Are there cases where members quit midway?
A. There are more than you might think. Because the activity itself is not easy, some people give up along the way. That is why we value willingness to participate and passion over technical skill. I believe that even with lacking knowledge, if you have the attitude of wanting to learn, you can grow sufficiently.
Q. Is the current team headcount sufficient?
A. It has gotten a bit better now, but during the period when parts needed to be manufactured before the vehicle actually rolled, the labor shortage was severe.
Even looking just at the powertrain, there are various fields such as intake, exhaust, cooling, power transmission, fuel systems, and ECU mapping, and the section lead must understand all of these parts.
As a result, we had to do our own work, help other sections, and even train new recruits. Since we also had to attend classes and carry out projects, it was quite difficult.
Q. What parts did you use before this MJF intake system?
A. Speaking based on last year’s vehicle, we used an engine with a smaller displacement than the current one.
As a result of senior data analysis, it was judged that even if a new intake system was designed, the performance improvement effect wouldn’t be significant, so only the restrictor was manufactured using the MJF method.
At that time, it was produced through a company called Icntec, and I heard that the production period took about one to two months.
Designing and manufacturing an entire large-scale intake system like this time is a first for us.
Q. How is the vehicle development situation currently progressing ahead of the competition?
A. There is about a month left until the competition. While intake and exhaust performance are coming out satisfactorily, additional improvements are needed in the cooling system. Currently, the most important task is cooling. No matter how good performance a vehicle puts out, if it doesn’t cool, it cannot run normally.
In particular, the structure we are currently reviewing is a method of placing radiators in parallel on the left and right, and in this case, the hydraulic resistance on both sides must be balanced. If the resistance on one side is excessively low, coolant will flow only that way, resulting in an effect similar to using only one radiator even though two are used.
Therefore, we continue to carry out flow channel design and flow rate analysis while repeating tests.
Q. I heard that you created the CFD and design data yourself.
A. Yes. Most of the data needed during the design process was organized directly.
For instance, we investigated temperature data for the region where the competition is held over the past 5 to 10 years to set design conditions. Looking at past data, the temperature during the competition period was around 38°C, so we set 40°C as the standard, and based on that, we also reviewed thermal conditions and the characteristics of the MJF material.
Also, to calculate the intake capacity, we performed liter-unit calculations and graph analysis, organizing most of this process directly in Excel.
Q. What programs did you use for analysis?
A. We mainly used ANSYS. We utilized various functions such as Fluent for fluid analysis and topology optimization. Even without physically manufacturing the product, inputting conditions similar to reality allows for quite accurate verification. Therefore, it is of great help during the design review process.
Q. Do you plan to use PA12 or MJF technology in the future as well?
A. We are reviewing it sufficiently. I think there is high applicability for parts requiring high durability or targets for weight reduction in the future as well. Of course, areas that strictly require metal, such as the vehicle frame or suspension, must use metal as they are. However, for parts where metal is overkill, utilizing 3D printing technologies including PA12 can yield weight reduction effects.
Q. What role do the aero parts applied to the vehicle play?
A. Aero parts generate downforce using airflow during driving. Because they press the vehicle down toward the ground, tire grip increases and cornering performance improves. Of course, on long straightaways requiring top speed, aerodynamic drag increases, which can rather reduce top speed. However, since the Formula Student Korea competition features more corner sections than high-speed straightaways, securing downforce is much more important.
Q. Do you also consider technologies like active aero?
A. Many teams are actually reviewing it. Methods of adjusting aero part angles depending on speed are also being studied. We ourselves have attempted to look into it in the past. However, considering implementation difficulty and priorities, we are currently focusing more on other areas.
Q. Are you currently serving as a driver as well?
A. Yes. Currently, we are in the stage of improving weak points of the vehicle while simultaneously collecting driving data. We are accumulating data such as vehicle wheel speed, TPS, RPM, and steering angle through sensors, and this data will also be utilized in designing the next season’s vehicle.
Q. What do you think is the greatest charm of this activity?
A. The thrill at the moment when a part I actually designed and made operates normally on the vehicle is immense. Of course, the process is tough. But seeing what we made ourselves actually move and performance improve is truly rewarding.
Q. Lastly, is there anything you would like to say?
A. From the perspective of a student team, collaboration with companies is a huge help because we have to run the team with limited budgets and resources. I sincerely thank Lincsolution and its staff members for trusting and supporting us. We will do our best to successfully complete the vehicle during the remaining period and create great results.
We sincerely wish TEAM NSSUR success in finishing the competition safely
Coordination Lincsolution Digital Manufacturing Business Division
Edit Lincsolution Marketing Team
