Why Pair These Two Tools?
Fusion 360 is excellent at detailed engineering. Parametric modeling, FEA simulation, CAM toolpaths, technical drawings. It does a lot, and it does it well. But if you've ever stared at a blank Fusion 360 canvas trying to figure out how to even begin modeling a bracket, you know the pain. Getting that first piece of geometry into existence is often the slowest part.
That's where Ragnar CAD fits in. You describe what you need (or upload a sketch), and within a few minutes you have a solid starting model. Export it as STEP, open it in Fusion 360, and pick up where the AI left off. The tedious "get something on screen" phase is done. Now you can focus on the real engineering.
The Workflow, Step by Step
1. Generate Your Model in Ragnar
Open app.ragnar.build and describe your part. Be specific about the dimensions and features that matter. Something like: "A mounting plate, 100x60x4mm, with four M4 clearance holes at the corners on 80x40mm spacing, and a central 20mm bore."
The more specific you are about critical dimensions, the less cleanup you'll need in Fusion 360 later. You can also upload a photo or sketch if you have one. Then iterate by conversation until the geometry looks right.
2. Export as STEP
Download the STEP file from Ragnar. This gives you real B-Rep geometry, not a mesh. That distinction matters because Fusion 360 will treat it as a proper solid body you can work with, not a faceted import that fights you at every step.
3. Import into Fusion 360
In Fusion 360, go to File > Open and select your STEP file. Alternatively, use Insert > Insert from my computer if you want to add it to an existing design. Fusion imports it as a solid body.
4. Make It Yours
This is where Fusion 360 shines. With the imported geometry, you can:
- Add precise holes, patterns, and fastener features
- Apply parametric dimensions so you can resize things later
- Run stress simulations to validate your design
- Generate manufacturing drawings with proper GD&T
- Set up CAM toolpaths if you're machining the part
Things to Watch Out For
Units. Ragnar exports in millimeters. If your Fusion 360 document is set to inches, you'll get a very tiny or very large import. Check your document settings before importing.
Timeline placement. Imported STEP bodies show up at the beginning of Fusion 360's timeline. If you're adding the import to an existing design, you might want to use the "Insert" approach rather than opening the file directly.
Feature recognition. Fusion 360 doesn't automatically run feature recognition on STEP imports the way SolidWorks' FeatureWorks does. The imported body is a "dumb solid" until you manually convert features. For most workflows, this is fine since you'll be adding new features on top of the import rather than modifying existing ones.
Body naming. If your Ragnar model has multiple bodies (like a multi-part assembly), they'll come in as separate bodies in Fusion 360. The names carry over, which makes it easier to keep track of things.
Where This Workflow Works Best
Rapid prototyping. Generate the overall shape in Ragnar, then add mounting features and tolerances in Fusion 360 before printing or machining.
Custom enclosures. Describe the enclosure dimensions and basic layout in Ragnar, then add snap-fit details, PCB standoffs, and ventilation patterns in Fusion 360.
Fixture and jig design. Describe the basic fixture concept in Ragnar, then add precision features, dowel holes, and clamping details in Fusion 360.
Student projects. Students can focus on the engineering decisions (where to put holes, what wall thickness to use, how to constrain the assembly) instead of spending lab time learning how to create a sketch and extrude it.
Get Started
Generate your first model at app.ragnar.build, export the STEP file, and open it in Fusion 360. The whole process takes under 10 minutes for a simple part.