Designing for SLS: Best Practices and Tips

Designing for SLS requires different considerations than traditional manufacturing or other 3D printing methods. Understanding these principles unlocks the full potential of laser sintering.

Fundamental Design Principles

Design Freedom

SLS offers exceptional design freedom through self-supporting builds, enabling complex organic shapes, internal features, lattice structures, and nested assemblies impossible with other methods.

No Support Structures

Unlike FDM or SLA, parts are self-supporting within the powder bed. This enables any geometry without considering support removal or orientation limitations.

Wall Thickness Guidelines

Minimum Wall Thickness

For PA12: 0.7-1.0mm minimum for sustained walls. PA11: 0.8-1.0mm for flexibility considerations. TPU: 1.0-1.2mm due to material properties.

Optimal Wall Thickness

1.5-3.0mm provides excellent strength-to-weight ratio for most applications. Thicker walls add material cost without proportional strength gains.

Thin Features

Thin fins and ribs as small as 0.7mm work well for short spans. Support ribs with gussets or thicken connections to main geometry.

Feature Sizing

Holes & Openings

Minimum hole diameter is 1.0mm. Holes smaller than 3.0mm may require drilling for precision. Design holes 0.3-0.5mm oversized for tight tolerance fits.

Text & Detail

Minimum text height is 2.0mm for raised text, 2.5mm for engraved. Use sans-serif fonts with 0.8mm minimum stroke width for legibility.

Gaps & Clearances

Minimum gap between separate parts is 0.4-0.5mm. Provide 0.6-0.8mm for parts that must separate easily after printing.

Mechanical Design

Threads

Internal threads M3 and larger work well. External threads down to M2 are possible but M3+ is preferred. Self-tapping screws work excellently in SLS parts.

Snap Fits

Design robust snap features with generous fillets, 2.0mm minimum thickness at base, and deflection limits appropriate for material.

Living Hinges

PA11 excels for living hinges with 0.3-0.5mm minimum thickness, adequate flex length, and properly oriented grain direction.

Design for Manufacturing

Powder Removal Consideration

Complex internal geometries must allow complete powder removal through escape holes or openings. Consider accessibility during depowdering.

Build Efficiency

Optimize part orientation and nesting to maximize build chamber utilization, reducing per-part costs.

Design for Assembly

Minimize part count through functional integration while maintaining serviceability and practical manufacturing.

Conclusion

Successful SLS design balances design freedom with practical manufacturing considerations. SinterX provides design guides and application support to help you achieve optimal results.