From hand-drawn sketch to a perfect, tweakable 3D model in 30 seconds. Gemini 3.7 Flash is an absolute game-changer for functional parts.
(Disclosure: I am the solo developer behind the app mentioned below, stl-er)
Yesterday, Gemini 3.7 Flash came out, and I immediately started testing it under the hood of my app, stl-er. After doing some prompt engineering, I am honestly blown away by the results.
The biggest highlight? I tested the new model's vision capabilities by uploading 2D drawings, one professional 2D drawing (not attached due to NDA) and two of my own hand-drawn sketches (see attached images and the resulting screenshots).
The interpretation was mind-blowing: 3 uploads, 100% correctness. It provided totally correct models in about 30 seconds each, and even mapped out all the relevant parameters for me to tweak afterward. It’s crazy.
Why this matters for 3D printing: Before this, I had tested almost every model up to Fable 5. Most of them heavily struggled with spatial understanding. Plus, earlier models like GPT 5.4 mini or Gemini 3.6 Flash were just too slow to run any kind of "medium thinking mode" without creating a terrible, laggy user experience.
It’s always a battle between speed, quality, and cost, but Gemini 3.7 Flash finally hits the sweet spot. It’s so fast that medium thinking mode is now perfectly viable. I did test some highly complex parts and eventually hit the model's limitations, but the ceiling has been raised significantly. The future of these models is going to be insane.
A bit about stl-er and why it's not just another AI mesh generator: My vision for stl-er was always to build a bridge from an idea to a print-ready model for people who just don't want to learn complex CAD. Under the hood, the app uses OpenSCAD to generate real CSG. Because we aren't just throwing together messy AI meshes, the app is built specifically for functional parts. It’s not meant for printing figurines or organic statues. We want parametric, watertight models for real-world parts.
- One of the biggest values of the app is the community aspect:
- All generated models go into a public community library.
- Anybody can pick a model, adjust the parameters, download it, and print it.
- Zero licensing restrictions. Do whatever you want with the files.
- It is totally free to browse the library and download up to 5 models per month (and absolutely no ad mobs).
One quick heads-up on logging in: Currently, you can only log in with Apple or Google. I know not everyone loves OAuth, but I actually had to remove the standard Email/Password login because bots started aggressively scraping the model library before the app was even officially released. Once I figure out a bulletproof way to verify emails, I'll bring it back.
I'm incredibly excited about where this is heading and glad we are on the right track. If you want to mess around with it, you can find more info and the App Store / Play Store links over at
stl-er.com