22 CAD Tips For Perfect 3DPrints

Editor’s Note: Billie was nice enough to work with us to create a custom version of her quick guide for volume 75 of Make: Magazine. You can download our version for free here, if you like this color scheme. Otherwise, enjoy Billie’s originals, the content should all be the same!

This infographic is part of a series of 3D printing poster guides that I have produced. You can access full-resolution copies of these guides for free so you can print your own; I also sell prints through RedBubble if you’d like to support me making more.

Make walls a multiple of your extrusion line width for a smooth slice. If it was 0.4mm use 0.8, 1.2, 1.6, etc.

Roughly 0.3mm clearance should be added between fitted parts using offset face at end of modeling process.

Combining fillets and chamfers mitigates the issues of fillets alone and smooths the chamfer.

Filament must be laid upon existing material, so avoid steep overhangs to reduce the need for support

Adding a fillet or chamfer between a wall and base strengthens the join by adding more interface.

Using parameters and constraints allows you to easily edit and iterate upon your designs. 10mm 45°

Vertical holes are fine, but horizontal ones should be tear-drop shaped to mitigate steep overhangs.

Fillets don’t work well from below, due to harsh overhangs. But they can look great in other areas.

Printers can bridge gaps between bodies quite easily. Distance varies, but most can easily handle 2cm+.

Vertical edge fillets increase quality by reducing inertia during harsh directional changes

Equal chamfers always work (even from below) as their overhang remains at a printable 45°.

A thin, sacrificial bridging layer can reduces the need for support material. It is cut away after printing.

Sacrificial, perpendicular ribs can be added to support overhangs during printing.

Reduce the risk of a print warping up from the bed by rounding out or adding mouse ears to corners.

Text looks best when indented into a vertical surface. It reduces overhangs and has better resolution.

Due to the planar layering of most 3D printers, print orientation has a significant impact on strength.

Curves look good with an axis in the Z direction, but due to the layering process can look very poor in the X/Y.

Use software that makes manifold objects (without tiny gaps or reversed faces), to avoid slicing errors

A slit, bolt, and trapped nut can be added to holes to allow them to be tightened around another part.

Complicated or fitted parts of an overall print can be isolated and printed to test for fit.

Compliance can be added to parts to enable flex, which enables push-fitting parts.

Diagonal ribs can be added to support/enable a roof to bridge between them. Can be beneficial inside a model.

If you get stuck with a design, the 3DPrinters community on Discord which I help run, is happy to help you out.

learn how to design in CAD by signing up for my class! I’ll teach CAD through the process of designing a chess set. Sign up HERE!

Happy Printing!