Designing for MJF

Multi Jet Fusion (MJF) is a powerful 3D printing technology that offers high accuracy and detail for functional prototypes and end-use parts. To ensure successful printing with MJF, here's a guide to consider during the design phase:

Wall Thickness and Features:

• Minimum Walls: Aim for at least 1mm wall thickness to avoid warping. Excessively thin walls can become distorted during printing.
• Maximum Walls: Avoid overly thick walls (above 10mm) as they can lead to uneven surfaces and internal stresses.
• Embossed/Engraved Details: Ensure a minimum depth and width of 0.5mm for embossed text or features to guarantee legibility after post-processing.
• Tapered Edges: Avoid tapering edges to zero and instead give a rounded edge of at least 1mm to avoid damage during post-processing

• Minimum Clearance: Design a minimum gap of 0.6mm between mating parts to prevent them from fusing during printing. Increase the gap for thicker walls (0.9mm for walls above 50mm).
• Interlocking Parts: Consider interlocking features for easy assembly and improved part strength. For large parts that will be printed in multiple pieces we can section for you and automatically apply the correct tolerances and optionally features such as lap joints, tongue and groove or dovetail joining methods.

Additional Design Considerations:

• Minimum Feature Sizes: Holes and shafts should be at least 0.5mm in diameter. Minimum font size for text is 6pt.
• Large Flat Areas: Break up large, flat surfaces with ribs or other features to minimize warping.
• Lattice Structures: Design lattice structures with a minimum gap of 1mm between elements for proper removal of excess material.
• Material Selection: MJF typically uses Nylon PA 12, offering a good balance of strength and printability. Consider if glass-filled variants are needed for increased stiffness.