Preview3D
for Mac, iPad, iPhone & Vision Pro
Open STEP, STL, OBJ, glTF, 3MF and G-code natively — with Quick Look previews, thumbnails and one-click conversion.
STEPSTLOBJglTF3MFG-codeUSDZ
$9.99 one-time
I build the tools I wished existed.
I’m Michal Fanta. I design 3D models in Onshape and print them on Prusa 3D printers — 289 of them on Printables so far. I also build websites and small, fast, native apps for Mac, iPad and iPhone. This is where it all lives, and where I write about how it’s made.
6
apps on the App Store
289
models on Printables
287k+
downloads
76k+
likes on Printables
7,900+
followers on Printables
Blog
Notes from the workbench
Stories behind the models, Onshape tricks and devlogs from the apps.
Tried Something New
Iteration: a sci-fi novella that exists because I love sci-fi
Eleven light years from Earth, four hundred days alone, and a ship’s computer. Iteration is my sci-fi novella about solitude and about what you can trust.
October 2026
Behind the Scenes
Voronoi right inside Onshape: how my FeatureScript came to be
A Voronoi pattern generator as a custom feature in Onshape — no detour through SVG and DXF, with parameters you can change at any time. Free.
October 2026
Tessellation in Preview3D is sharper again
Preview3D 1.4.2 is out for Mac, iPad and iPhone.
October 2026
Tutorial
Blender on buttons: a profile for the Logitech MX Creative Console
Vertex, edge and face selection, the modelling tools and snapping, with Blender's own icons and keys that show what is currently switched on
October 2026
Apps
Small, fast tools for people who make things
Each one does a single job, natively — without asking who you are or sending your files anywhere.
StepKit
for Apple platforms
A from-scratch, pure-Swift STEP (ISO 10303) loader, B-rep kernel, tessellator and Metal viewer — no third-party CAD kernels.
MaciPadWebsite
3D models
Designed in Onshape, shared on Printables
Functional prints, toys and organizers — 289 models since 2018, downloaded more than 287,000 times.
About
Hi, I’m Michal.
Under the name xfanta I model for 3D printing, and since 2018 I’ve published 289 3D models on Printables, all designed in Onshape and then printed on Prusa 3D printers. I also build websites and apps, and most of it started as something I needed myself: a quick look at a STEP file without opening a CAD package, a box for printer parts, a hinge you can’t see.
More about me