Design guidelines
Practical rules of thumb from our engineers to yours. These aren't academic — they're the things we wish every CAD file arrived with.
Designing for LPBF isn't as different from conventional manufacturing as people think — but the places it diverges matter a lot. The rules below apply across most of the alloys we print. For specifics, talk to one of our engineers; we'd rather spend fifteen minutes on a call than fix a part later.
The essentials
Nine things to get right
Thinner than you think, thicker than you'd hope
Minimum printable wall: 0.4 mm for short features, 0.6 mm if the wall is load-bearing or taller than ~20× its thickness. Below that, expect distortion and surface roughness you won't love.
Keep surfaces above 45°
Angles ≥ 45° from horizontal print cleanly without supports. Between 30° and 45° you'll get a rough down-skin. Below 30°, plan for supports and a post-machining step.
Circles become teardrops
Horizontal holes smaller than ~8 mm diameter should be teardrop-shaped so they print without supports. Internal channels need an exit for powder — design a cleaning path from day one.
Give moving parts room to breathe
For mating features that shouldn't fuse, leave at least 0.3 mm radial clearance. For press-fit tolerances, expect ±0.1 mm on features and ±0.2 mm on overall size before post-machining.
Orientation is half the design
The same part printed two different ways can differ by 30% in mechanical properties. Talk to us early about which surface needs the best finish, which direction carries the load, and where supports are acceptable.
Design to remove them, not avoid them
Some supports are unavoidable. What matters is whether a hand or a tool can reach them. Closed pockets with support structures inside will cost you more in post-processing than the print itself.
What you can hit as-printed, what needs machining
General as-printed tolerance is roughly ±0.2 mm up to 100 mm, then ±0.2% beyond. Bearing seats, sealing surfaces, and critical fits should be called out for post-machining up front.
Every side has a different texture
Top surface: ~Ra 8–15 µm. Vertical walls: ~Ra 10–20 µm. Down-skins: rougher. If you need cosmetic surfaces, plan for media blasting, tumbling, or machining — each adds cost but gives predictable results.
Stress-relieve before you do anything else
Almost every LPBF part ships through a stress relief cycle straight off the plate — residual stress will bite you during wire EDM, machining, or service. Hot isostatic pressing (HIP) is worth it for fatigue-critical parts.
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