What I learned about designing for 3D printing in Fusion 360

19 May 2026

Just some notes…

Right tool for the right job

Complex meshes for organic models get edited in Blender, not CAD

Project lines and faces

Use project (hotkey p) in sketch mode to project features into a new sketch plane. This is the key to not having a bunch of lines in one sketch and then losing track of what they all mean

Dimension sketches

Use dimension (hotkey d) to position sketch elements where they are supposed to be. For example, a cable cutout that needs to be 16mm from an adjacent feature can be sketched roughly and then constrained to the correct location

No fillets/chamfers in sketches

Unless considered part of the design, these should not be in your sketches as they force removal of constraints and make it hard to reuse the sketch later as a projection.

If you already included these features and they are causing problems in downstream sketches, you can delete fillets from the sketch and then use the extend tool to restore the original sharp corner.

Do the big fillets first and the smaller ones last, to prevent errors.

Name sketches

Rename sketches to be something useful, eg cable cutout not sketch16

Bodies vs Components

Use bodies for simple parts (eg beginner projects), components for assemblies with repeated or moving parts. Starting with an Assembly file instead of a Design file will stop extrude from working.

Making circuit board enclosures

Model something to hold the board (horizontal), extrude it
Sketch on the side of the new object a cool shape and extrude it
Use “split body” to create a top and bottom shell
Add cut-outs
Fillet

Spline base + split body works really nicely for this workflow (Inky impression desktop frame).

Examples:

Designing for 3d printing

Heat set inserts = game changer
If you can tolerate a visible nut, sunken nuts are a very strong fastener. If you’re out of heat set inserts and don’t want the nut visible, they can be superglued in place but are nowhere near as strong
Use simple tongue-and-groove step joints to keep parts aligned. Sometimes this can effectively replace hardware fasteners too
Use big smooth corners on the build plate to prevent warping
Don’t forget tolerances
Print with basic filament first, and expect to do a few test prints
No need to hollow-out features to “save plastic” - your’re not, since infill already accounts for this.
Use the section analysis tool to see a cut-through of your design’s hidden faces
Check check check before printing

Part Strength

Use classic strong features to strengthen a design, not infill, as it does not help bending resistance.
Examples: “L” , “I”, “T”, braces

Tips and Tricks

For my next project:

Parameterize dimensions such as case_clearance
Photograph circuit boards and insert into the drawing, then use as reference for cut-outs, etc

geoffwilliams@home:~$