Chuck Hellebuyck's 3D-Printable Hot Wheels Tracks Are Modeled Through Scanning — on a 2D Scanner
Rather than modeling the parts from scratch, Hellebuyck used a traditional flatbed scanner on a cross-section of existing track.
Maker Chuck Hellebuyck has come up with a clever way to reproduce toy car racing tracks on a 3D-printer, getting exactly the right shape — by pushing a cross-section of original track against a traditional two-dimensional flatbed scanner.
"I used my paper scanner to scan the edge of a Hot Wheels track so I can turn it into a 3D print," Hellebuyck explains. "I've been playing with Hot Wheels track, trying to make something bigger for my grandson, and I want to make it more permanent with a wood structure and then finish it off with model train accessories. A lot of people who build these buy these 'Crash Circuit' kits from Walmart or Amazon, and they use the pieces to build their track. The kit includes some of these straight sections, but I need a lot of them."
While the option is always there to buy multiple kits in order to finish building the layout, that's not exactly the cheapest approach — and leaves a lot of unneeded curved sections going to waste. The original track pieces are also surprisingly flexible, so much so that they can pull apart when positioned at an angle — which left Hellebuyck deciding a better approach was to model and print his own track sections instead.
Accurately modeling a 3D object to match a real-world equivalent — close enough so that the replacement parts can mate with the originals without gaps or bulges that would send cars careening off-track — can be a challenge. A 3D scanner can make things easier, but they're not cheap — so Hellebuyck turned to a device he already had on his desk: a traditional 2D flatbed scanner, more commonly used for digitizing documents and photographs.
"I thought, 'why couldn't I scan the edge of this track and reproduce it,'" Hellebuyck explains. "I brought [the scan] into a graphics editor [and] used the scan as a guide, thickened up the walls, and then I exported it as an SVG [Scalable Vector Graphics] file, brought it into Tinkercad, and then I could clean it up further."
With further modification — making sure the model matched the original piece's dimension, adding in missing bumps, and the like — the replacement track was ready to print. The advantage of having the model, too, is that Hellebuyck wasn't limited to just the dimensions of the original kit parts, instead being able to design longer pieces that would provide a smoother running surface with less likelihood of disconnection during uphill or downhill stages.
The project is documented in full in the video embedded above and the the CHEP YouTube channel.