Various 3D printing processes are different in capabilities and design restrictions, but there are same key design considerations of all 3D printing processes. If you have finish your 3D designing and modeling, keep this information graphic for a quick reference.
Digital VS Physical
All your digital design of 3D printing will transfer into a physical object. There are now physic lows to adhere in digital design environment, like gravity. Anything can be design in 3D on digital canvas, but it doesn’t means everything can be 3D printed in reality.
General Design Considerations
All 3D printing processes manufacture parts with layer-by-layer methods. Materials cannot be deposited on thin air without support, so every layer must printed over underline materials.
Overhangs are model areas, which are supported by either layer materials or without supporter. There is an angle limitation for 3D printing without support material. Such as FDM and SLA, the angle is almost 45 degrees. Limitation of overhang in models can avoid rough surface finishes on support area.
In 3D printing design, wall thickness is another factor you need to keep in mind. As 3D printing process produce accurate features up to a certain point. Different 3D printing methods will require various minimum wall thickness, as in our practice, we recommend your model wall thickness should be more than 0.8mm, which can be printed successfully with all 3D printing process. Less than 0.8mm wall thickness need 3D printing test, in order to encounter potential problems in 3D modeling programs.
Once we design a 3D model, we never ignore a significant factor of warping. In 3D printing process, materials will be melted, sintered, and then solidified with a laser scanning. The heating and cooling process of material will give rise to parts warping.
3D printing parts with large and flat surface are especially prone to warping. We can avoid warps by using correct machine calibration, or adapting adequate surface adhesion between parts and printing bed. In ZCMIM practices, large flat surface should be avoided in design, and it’s better to add rounded corners in 3D models than right angle corners.
Level of detail
In 3D printing, each process has different minimum feature size of production, we need to keep these information in mind and follow these principle in 3D model design with intricate detail. The minimum level of details are decided by 3Dprinting process capability and mechanic, some times are connected with selected layer height.
3D printing production speed and cost are impact by the process types and materials selection. So smaller detail features are important in your model designing.
Rules of Thumb
- Avoid overhangs in design if possible, or use overhangs angles smaller than 45°.
- Wall thickness should be at least 0.8mm in models.
- Avoid large flat surface and using rounded corners to eliminate warps.
- Decide minimum features detail level according with 3D printing process.
Specific process guideline
If you are designing with specific 3D printing process. Follow below links for full guidelines of each process:
SLS 3D printing Design Guideline
SLA 3D printing Design Guideline
FDM 3D printing Design Guideline
Binder Jetting 3D printing Design Guideline
DMLS 3D printing Design Guideline