I design little 3D-printable cars for my son. He has the printer, so I make the files and he gets to print them. Somewhere along the way I figured other people might want them too, so I put them up under SaiyanPrints.
The cars are 1:64 scale toy bodies that sit on one shared chassis. A body pushes onto two posts and pulls off again. Paperclips work as axles. One chassis can wear several bodies, or you can print one chassis per car. The idea is simple. Getting the fit right in CAD is most of the work.
This post is about that CAD split: Blender for the body, SolidCraft for the platform and the fit.
Why two tools
A car body wants soft surfaces, glasshouse proportions, panel lines, and a silhouette you recognize from across the desk. Blender is good at that. I sculpt and refine the shell there until the shape reads as the car I meant, without naming any real brand or toy line in the files or the shop copy.
A chassis wants numbers that stay put: wheelbase, track, post spacing, wheel keep-outs, wall thickness, and the clearances that keep a body from hitting a tire when it snaps on. That is parametric work. When one dimension moves, the rest should rebuild. I do not want a pile of frozen meshes to fix by hand.
SolidCraft is the open-source parametric CAD I use for that second half. It is written in Rust. You sketch, constrain, build solids on a feature timeline, and change a parameter when the platform needs a tweak. Desktop, browser, CLI, and an MCP server all run the same commands. Docs live at docs.solidcraft.io. I am a user of the tool, not the vendor. I mention it because the fit side of SaiyanPrints needs a real parametric stack. The project tag is #SolidCraft.
The shared platform
Every SaiyanPrints 1:64 body is built to one mount interface on one standard chassis.
Public facts that stay stable across the live kits:
- Wheelbase is 44 mm.
- Front wheels are 11 mm; the rear can stay 11 mm or use the optional 12 mm staggered rear that ships with the kits.
- Bodies are single-piece shells that push onto two keyed posts.
- Axles start as two standard paperclips per car. An adult cuts and files the wire and drills the axle holes with a 1.2 mm pin vise. The README in each download walks through it.
- Print guidance on the listings is PLA, 0.4 mm nozzle, 0.12 mm layers, no supports, bodies upright rim-down as supplied.
The free R1 Roadster 1:64, the Garage Starter Trio 1:64, and the Euro Sport Pack 1:64 all reuse that same chassis and the same classic 5-spoke wheels. The Wheel Pack 1:64 swaps the rims without asking you to reprint the body. If you already printed a chassis for the Roadster, it fits the paid packs too.
I keep brand names and franchise names out of the public car names on purpose. Hot Hatch, Box-Flare Sedan, Flat-Six Coupe, Hatch Coupe, Pop-Up Coupe, Pocket Roadster. Those labels describe the shape, not a licensed model.
Blender owns the shell
In Blender I work one body at a time.
I block the silhouette to true proportions off the 44 mm wheelbase, keep sturdy walls (about 1.2 mm minimum in the platform rules), and leave the mount sockets and wheel wells for the fit pass. Panel lines on these kits are fine, about 0.2 mm wide in CAD. They may soften on some printers. That is called out on the product pages.
I do not treat the Blender file as finished when it looks good in a render. The body still has to seat on the posts, clear the wheels, and print without supports in the orientation we ship.
SolidCraft owns the fit
In SolidCraft I keep the chassis, wheels, axle geometry, and the mount interface as parametric parts. The body comes over from Blender for a fit check against that platform.
What "CAD-checked" means on SaiyanPrints listings:
- The body seats on the chassis posts in CAD.
- Walls and keep-outs meet the platform rules in CAD.
- Print time and gram estimates come from the slicer, not from a stopwatch on my desk.
What it does not mean:
- I have not print-tested these kits end to end.
- Rib grip, drill feel, wheel press, and pull-off force are still unproven until someone prints them and tells me how it felt.
I would rather ship a clear CAD claim than invent a print farm I do not run anymore. About 4 years ago I was running 12 printers and moving a lot of filament but things have shifted slightly for me.
One body at a time
The standing workflow is slow on purpose.
- Model the body in Blender until the shape is right.
- Bring it to SolidCraft and run the fit checks against the shared chassis.
- Polish the body if the fit pass finds wall, foot, or clearance issues.
- Only then package the download with the standard chassis and wheels.
I do not batch five unfinished bodies and assume the mount will still fit. Each body gets its own fit pass. A pack ships when every body in it clears the same platform. I do not ship just to hit a date.
That is also why new packs show up as small sets instead of a hundred SKUs on day one. Garage Starter Trio is three sport-compact bodies plus a bonus hardtop. Euro Sport Pack is three European-inspired sport bodies. Same chassis, same mount, new shells.
What I leave out of the public story
A few things stay off the product pages and off this post on purpose.
I do not put third-party brand or toy-line names on the cars. Inspiration is allowed. Copying a trademark into a title is not.
I do not claim a print I have not done. If you print one of these and it works, or it does not, that feedback is more useful than another marketing screenshot.
I also do not rush a pack to fill a gap in the catalog. If a body still needs a fit pass, it stays in CAD.
Try the stack, or just grab a car
If you only want the cars, start with the free R1 Roadster, then add a pack when you want more shells on the same chassis. Personal downloads on the store are $1.99. Commercial licenses are listed on each product page.
If you care about the CAD side, Blender handles the organic work. SolidCraft handles the parametric work. I build SaiyanPrints on that split because each tool is good at the job I give it.
Shop: Saiyanprints.com SolidCraft: solidcraft.io · docs · #SolidCraft