Design for Additive Manufacturing (DfAM) isn’t optional—it’s the difference between a clean, functional print and a warped, unsupported mess. Whether you’re building for FDM, MJF, SLS, or SLA, these 20 questions will help you check your assumptions and optimize your design before committing to production.
1. Why does print orientation matter so much in AM?
Because strength is anisotropic—parts are typically weakest in the Z-axis. Orientation affects mechanical integrity, surface finish, print time, and support structure requirements.
2. What’s the minimum wall thickness I can use?
It depends on the process, but general rules: 0.8 mm for FDM, 0.5 mm for MJF, 0.75 for SLS, and 0.5 mm for SLA (supported). Go thicker for high aspect ratios or stressed areas.
3. How do I reduce support structures in my design?
Use chamfers, self-supporting geometries like arches or teardrops, and orient parts to reduce downward-facing surfaces.
4. What is the biggest risk of printing without proper drainage in closed parts?
Trapped resin or powder. It can cause swelling, add weight, create contamination, or fail in post-processing. Add vent holes.
5. How accurate is additive manufacturing really?
±0.2–0.3 mm is typical for most polymer AM processes. Tight tolerances require compensation or machining.
6. Can I rely on AM for interference fits?
Sometimes. Materials like nylon or TPU may flex or absorb moisture. Always prototype interference fits to validate dimensions and holding force.
7. How should I design holes and slots for standard hardware?
Oversize slightly. A 6 mm bolt hole might be drawn at 6.3 mm to compensate for material behavior and print variance.
8. When should I consolidate parts?
When you want fewer fasteners, less assembly, and better mechanical integrity. If it can be one part instead of five, consolidate.
9. What features are most likely to fail in bad designs?
Thin unsupported walls, long bridges, sharp overhangs, and small vertical pins. All are common DfAM pitfalls.
10. How do I know if a part is too thin to print?
Check your printer’s specs and do a test print. Thin walls below process minimums won’t resolve correctly and may fail structurally.
11. Which materials offer the best all-around durability?
Nylon (PA12) and ULTEM™ 9085 offer high toughness, thermal resistance, and chemical stability for functional parts.
12. Which materials are easiest to print?
PLA and PETG (for FDM), or standard PA12 (for MJF/SLS). These offer good reliability with less process complexity.
13. Can I print functional threads?
Only coarse threads work reliably. For precision threads, tap or insert them post-print. Consider heat-set inserts for strength.
14. How do I make sure my part prints efficiently?
Minimize Z-height, orient parts to reduce support, and avoid unnecessary detail in non-critical areas.
15. What surface features print best?
Bold, sans-serif text ≥2 mm tall, ≥0.4 mm deep. Logos and markings should be placed on flat or slightly convex surfaces.
16. What’s the best strategy for high-volume printing?
Use part nesting, minimize Z-height, and orient parts for repeatability. Dense nesting improves yield in MJF/SLS especially.
17. Should I plan for post-processing during design?
Absolutely. Design to minimize supports, allow access for sanding or machining, and leave stock on toleranced surfaces.
18. Can AM replace injection molding?
For small part volumes under 1,000 units or complex, custom parts—yes. But DfAM is key to hitting performance and cost targets.
19. What’s the #1 mistake in AM design?
Assuming that if it prints once, it’s good to go. Design for repeatability, not just printability.
20. When should I get a DfAM expert involved?
Ideally before finalizing your design. Early consultation helps avoid expensive, time-consuming fixes after production begins.
Need help answering these questions for your next project?
At RapidMade, we help engineers design smarter, print faster, and build better—whether you’re prototyping or scaling to production.
For the best 3D printing services visit rapidmade.com or reach out to [email protected] to get started.
