After the introduction of the 3T Sports Sedan and the 2C Sports Car, Thirdwigg Motors was ready to start exploring the electrification of vehicles. Since the previous vehicles all had internal combustion, in order to more into electrification, some testing was required. The car features a single electric motor just forward of the rear axle. Geared up 3:1, the motor provides sufficient acceleration and top speed.
Since this is track car suspension and bodywork are crucial for performance. The flat bottom of the car contributes to downforce, as does the rear wing and aerodynamic bodywork. The front and rear suspension is independent with torsen bars at each corner. There is very little wheel travel, appropriate for a track car. Steering is handed with the steering wheel, and the HOG just above the driver’s head.
The car was a good exercise to test a different drive mode in a LEGO car. Another electric car will soon be coming from Thirdwigg Motors, so this test vehicle was a good first step. The suspension was a little soft; it worked OK which was my experience with the Octan F1 as well. Frankly, the torsen system only works great for tanks in my experience, but maybe with a little work, it can have an application in future cars.
3T Sports Sedan was the inaugural car for startup Thirdwigg Motors, and the market requested another, smaller, sportier offering. The board of directors approved development of the 2C to fill this need.
Full gallery including instructions may be found here.
I wanted to keep the scale and keep many of the best parts of the 3T in this design but change the body style and add a couple of features. Very early I decided on a two door with a mid or rear engine. I wanted to get a better transmission, so with this, I set of to work. I scaled the car to the Porsche Cayman, and started fitting in parts. I used the same suspension from the 3T in both the front and rear, which constrained how the driveline would have to be routed.
It was at this point that the interior setup got a little complicated. When I started this car, the new Wave Selector was just release which optioned a lot of gearbox options. After seeing this great little transmission, I knew I had what I wanted: a four speed sequential transmission. After playing with some options, I place it in the middle of the car. I toyed with having the engine behind the rear axle, but settled on a mid placement. Nothing larger than a Flat 4 was ever considered. The four speed gearbox worked and a changeover axle ran to the front under the suspension where a simple rotation limiter was placed. The steering HOG and steering wheel had all of their mechanics in front of the transmission, so everything fit.
I had intentions of having a ratcheting gear selector to work with the slick sequential transmission. But I was running out of space. The center of the car was taken up with the transmission, suspension at each end, and placing one in the rear did not give a way to connect to the transmission. So the only place left was under the front hood. There were a number of great change over options that work well. I tried each. Some fit, some worked great, but each had the same problem: there was not good way to seamlessly integrate the “button” into the bodywork. I had visions of pushing on a grill to actuate the mechanism, but the grill was not very big, and required even more space than I was already using. In the end I decided to scrap the idea of a changeover, and use a simple rotary selector. It is not fancy, but it works well, and keeps the bodywork clean.
Through out this process I was toying with ideas for the body work. Generally, I add parts as I like them, and when everything is placed, I rebuild the whole car with structures in place for all the final placements of critical internal and external parts. But this car had a large transmission in the middle which meant there was no frame running from the front to the rear. I added a structural frame under each door, and tried to build up the frame under the transmission as best as I could. It works, but there is still a little car flex under heavy center load.
First, the bodywork on this car works better for my eyes than the 3T, even though I tend to like sedans a little better. Second, the gearbox worked flawlessly. It was smooth, and even though I had the open the hood the change gears, the smoothness was worth it. Finally, the suspension worked great as it had proved itself in the 3T. It now adorns the desk at my work. Hopefully you enjoy it too.
Don’t worry, Thirdwigg Motors is already hard at work on the next car.
The sport sedan is my favorite kind of car. You can have your McLaren, if I can have four doors and a long hood. One with the proportions of a C-class, the suspension of the ATS, the engine of a Mazda 6, the suede interior of the M3, and the value of the G70. Don’t worry about me, I’ll be set. But there are few good sedans in LEGO, and even fewer smaller ones. Let’s change that.
When I set out to make a sedan, I wanted it to be smaller. What were the features I could add in a smaller LEGO car? It had to have some style, suspension, a gutsy engine, steering, and a transmission. Finally, it had to be strong. So I got to work. The scale was set on a 3 Series that was a little wide, so I set the hardpoints and set off to work.
I first set the two axles and suspension. I have built a couple cars with a floating rear differential, and this setup has worked well in the past, so it would work well for this car. Each side had a dual arm independent setup with two shock absorbers. The front suspension used a dual A-arm setup and a wheel hub with only one hard shock absorber. Before adding the steering, the driveline would need to be finalized.
I played around with a number of transmissions, but settled on a simple two speed design for a number of reasons. First, it was smallest as something else would take a lot of space from the interior. Second, something better would take away from the rigidity of the model. Sedans need a lot of support through the transmission tunnel as you lose a lot of rigidity near the doors. Finally, anything more complicated than 2 speeds would be tricky to manually operate (play with) in this scale. About half way through my work on this project, some fun new gears came out which improved the design.
Next, I moved on to the bodywork. This is the part that causes me the most problems in my car builds, and this car was no exception. I set the doors first as I wanted to use two panels for each side. Then I worked on the front and rear bumpers. The rear came together quickly, but the front took a little more time. I wanted something that was sporty, and with a simple grill. I think it worked out well. Finally was the roof and the rear quarter panels. This part took a long time, as I wanted something strong and stylish. The result is strong and has the C pillar split into a D pillar. It is not perfect, but it is stronger than all the panel ideas I tried.
After the bodywork was set I did something I have never done before, I rebuilt a second whole car. This time, I knew all the final features, and where all the body work would attach so I could focus on creating a strong frame that would best support the whole design. I am happy I did this, as it cleaned up the inside, found some new solutions, and made the whole car stronger. Building this way also helped me think through how clear instructions could be made.
In the end, I was pleased with the final design. It accomplished all the goals I wanted, and it is an accessible design for others to recreate. I love building in this scale, and cars are a lot of fun, so I will need to do another small car design again.
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