When it comes to building decent aerodynamic devices, you want to focus on getting your geometry accurate, and making sure your parts are strong enough to deal with the force they’re generating. This build from [Engineering After Hours] delivers on those fronts, consisting of a high-downforce wing for a small RC car.
The video points out that, at best, even a decent RC car will have pretty crappy aerodynamic parts from the factory, with a lift-to-drag (L/D)ratio of 2-3:1 at best. This means that, while they may create some small amount of downforce, they’re also creating plenty of drag at the same time.
The dual-element wing designed here is much more efficient, hitting an L/D ratio in the vicinity of 17:1 – a huge improvement. Even a casual eye can note that the design looks a lot more like something you’d see on a full-size car, versus some of the whackier designs seen on toys.
The wing is built with a forged carbon fiber process using 3D-printed molds, to give the wing plenty of strength. Given that it’s built for an RC car that can do over 100 mph, making sure the wing is stiff enough to perform at speed is key.
[Engineering After Hours] does a great job of showing how to prepare the molds, fill them with carbon fiber, and pour the resin, and discusses plenty of useful tips on how to achieve good results with the forged carbon process.
The result is an incredibly impressive rear wing with aerodynamic performance to match its good looks. It may be more complicated than 3D printing, but the results of the work are that much tougher.
We’ve seen other aero experiments from [Engineering After Hours] before, too. Video after the break.
FRP ( Fibre Reinforced Plastic) is a wonder material from a pure engineering point of view, making it easy to create high performance designs, but at a huge cost to the environment, and so these days I find products that use large amounts of FRP without a great reason, somewhat jarring. It would be great if there was a car race formula which specified that the competing cars must be made mainly from sustainable materials.
It’s inconvenient, so people won’t go for it.
To kwikius
The uber trip you used to get to work this morning had 5x the environmental impact than it did to bring this rc wing into existence.
Interesting claim
Let’s see the numbers
RC cars have a regulatory body called ROAR which sets rules for the dimensions of wings for several reasons but one being safety. It is no secret that aerodynamics could be improved by placing a bi-level wing above the disturbed airflow of the body shell, much like we do in 8th scale off-road racing. But if that wing was made out of this carbon reinforced material, it would shatter on the first impact and in a wreck could seriously harm a spectator or corner marshall (individual that flips wrecked cars over during a race).
This type of carbon would have to hit a wall at full speed for it to get anywhere close to shattering. And on top of that, the cars that it would be equipped on are not heavy enough to cause any real damage to the spoiler. I don’t think you have any idea how strong forged carbon parts actually are. It is a slight bit less strong than twill weave, however, still very resilient.